Aussie Lapidary Forum
LAPIDARY => Tips and Gadgets => Topic started by: MakkyBrown on August 18, 2015, 08:53:12 PM
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I thought I'd start a thread to keep this in one place as hopefully others will do this and we can share ideas to improve our machines.
As a new owner of Tom Herbst' faceting books the first thing I did was turn to the digital encoder build pages and had already purchased a lot of parts before the books arrived I was that keen. http://www.facetingbook.com/books.html (http://www.facetingbook.com/books.html)
I put a lot of thought into which encoders I could mount on the machine and I was initially going to mount the encoder in front of the large brass nut on a raised mount. This wasn't ideal and would have resulted in the wires moving as you lifted the hand piece up and down. I had been in email communication with Rusted who suggested putting a small shaft through the centre of the shaft the large brass nut goes onto. This was something I hadn't thought of and a great idea :) , so rather than drilling the current shaft and potentially wrecking it, I turned up a new shaft with a 2.7mm hole through the centre of it and a fine thread on the side the dome nut goes onto. I've fitted it all without drilling any holes into the machine so it could easily be converted back to it's original specs.
The movement is transferred to the encoder wheel down a 2.5mm shaft. Luckily(to my amazement ;D ) my new shaft I turn up is pretty much perfectly true so the movement can be transfered back down the smaller internal shaft without any flex or need of a pivot. The large brass block the encoder mounts onto replaces the nut and is half threaded/ half 2.5mm brass bearing, and honey comb drilled to reduce weight.
I have modified Tom's code/files a little bit to suit my build. Happy to help anyone else that's purchased Tom's books and is wanting to have a go BUT I'm not a good enough machinist to make new shafts for other gemmasta's. The screen looks a lot better/brighter than in the photos. I also had to replace the angle adjuster knob with a lever, turns out it's really nice to use, far more ergonomic.
Hope someone finds this useful.
Cheers
Andrew
(http://aussielapidaryforum.com/forum/gallery/7/medium_5704-180815203721.jpeg) (http://aussielapidaryforum.com/forum/index.php?action=gallery;sa=view;id=7547)
(http://aussielapidaryforum.com/forum/gallery/7/medium_5704-180815203932.jpeg) (http://aussielapidaryforum.com/forum/index.php?action=gallery;sa=view;id=7548)
(http://aussielapidaryforum.com/forum/gallery/7/medium_5704-180815204117.jpeg) (http://aussielapidaryforum.com/forum/index.php?action=gallery;sa=view;id=7549)
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That is absolutely brilliant. Awesome.
What encoder did you end up using?
I hope one day to get some thing happening on mine using a PICxx. RPM was another feature that I thought may be handy. But that is great.
Cheers
OP
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Great work Andrew, it looks terrific. Have you tried it out yet?
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Great work Andrew, it looks terrific. Have you tried it out yet?
Sure have Bucket , I've cut 3 stones so far with it , angle encoder is spot on and has basically no error. Though hasn't got the resolution to cut with by itself imo. The depth of cut indicator(separate circuit) has taken a bit of sorting but I'm getting used to it. Today I cut a set of mains using just the indicator without checking as I went and they were perfectly even. The program also stores angles used on screen two, you reference back to them, then dial them in etc quickly.
That is absolutely brilliant. Awesome.
What encoder did you end up using?
I hope one day to get some thing happening on mine using a PICxx. RPM was another feature that I thought may be handy. But that is great.
Cheers
OP
The encoder is a US Digital E2 encoder, 1250cpr,5000ppr gives me 0.072 degree steps. The encoder also has an index so the unit recalibrate every time the hand piece is lift above roughly 95degrees. I got it for about $50 of ebay, I'd like a 5000cpr encoder but they are a expensive with the weak AU$$ and imo not sure if there would be any real advantage in getting one over the one I have. Maybe one day as it would be easy to change.
Might have to look into rpm I could display it where the unneeded title is on the screen.
Cheers
Andrew
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Thats a great job Andrew.
Glad you got the interference problem sorted.
I have several different screens coming, I ordered a 16 character by 2 line board and then realised it probably wasn't big enough so ordered the right one and then found a full colour touch screen so ordered one of those too, so there should be plenty of room to put RPM. Room temperature, Real time clock, minutes to lunch time, days to my birthday, endless possibilities, just to show off. :D
Knock off Chinese Arduino boards and shields are really really cheap.
I am still waiting on my encoder, pacing back and forth like a caged lion.
Paul
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Good work.
If anyone wants to do (or collaborate on) an instructions document for this, happy to put it up in the downloads section.
There are lots of old gemmastas out there that could benefit from a tech upgrade.
cheers
Leah
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Rusted,
I find every time I send an email about where is my parcel it will turn up the next morning. ;D
One thing I did buy locally was the alloy enclosure from Jaycar, it was hard to find a cheap one on ebay. It was a perfect snug fit for all the bits.
http://www.jaycar.com.au/Enclosures-%26-Panel-Hardware/Metal-Boxes/Diecast/Economy-Die-cast-Aluminum-Boxes---119-x-93-5-x-56-5mm/p/HB5064 (http://www.jaycar.com.au/Enclosures-%26-Panel-Hardware/Metal-Boxes/Diecast/Economy-Die-cast-Aluminum-Boxes---119-x-93-5-x-56-5mm/p/HB5064)
Webpage says out of stock but my local store had heaps. The screen and Uno are mounted(screwed) to plastic feet I glued to the alloy. The Uno is mounted to the lid making it easy to access which is handy as I have to disconnect the +ve and gnd for lcd before the Uno will let me upload code.
Cheers
Andrew
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Leah,
I should have taken some more pics :) before it all got calibrated. Not quite sure how to go about an instruction set as it will be variable how each individual would build this. I'd also like to get an ok from Tom Herbst as I feel anyone building this should atleast buy his books as a thankyou for the idea and base code. Technology, arduino support codes, wiring all change very quickly. I found I had to make a good few changes to get it all working. More than happy to help others building this with what knowledge I have(code, components, wiring I used etc), but step by step instructions could be a bit tricky. Maybe(not sure what's possible) a members folder location to put build pictures, arduino code, useful links, parts lists etc could be handy as this thread could become lengthy.
Cheers
Andrew
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More than happy to help others building this with what knowledge I have(code, components, wiring I used etc), but step by step instructions could be a bit tricky. Maybe(not sure what's possible) a members folder location to put build pictures, arduino code, useful links, parts lists etc could be handy as this thread could become lengthy.
Cheers
Andrew
No problems to keep all in one long thread - doesnt really matter too much if there are a few pages to scroll through. Might be an idea to keep any related pictures in one single gallery album though if there turns out to be more than a few. I can create one if you want me to.
cheers
Leah
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My encoder just arrived, Yahoo.
Its wired already with screened cable so I might be able to eliminate all the mucking around with screening and ferrite slugs.
As I have almost the full build to do apart from the shaft I will take lots of pictures so together we might be able to get an instruction sheet up.
My encoder is quite a bit deeper than yours and has a shaft sticking out about 12mm so the mounting is going to be different and I dare say a bit messier than yours, certainly a bit of thinking to do. I am going to need one of those lever type knobs too.
I was going to contact Tom Herbst myself to ask permission to use his Gem101 diagram at the club but I couldn't see a way of contacting him. I know he is sometimes on the gemology forum so we might need to go via that forum.
Paul
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I'll pm you his email.
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a US Digital E2 encoder, 1250cpr,5000ppr gives me 0.072 degree steps. The encoder also has an index so the unit recalibrate every time the hand piece is lift above roughly 95degrees. I got it for about $50 of ebay,
Thanks for that. You've certainly got the old brain box thinking.
An instructions thread would be a great idea. Tips, photo's, tutorials, code, etc..
Cheers
OP
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what an awesome upgrade to the Gemmasta. i would love to see some photos of the angle adjuster lever, i don't have this feature at all on my machine.
Troy
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a US Digital E2 encoder, 1250cpr,5000ppr gives me 0.072 degree steps. The encoder also has an index so the unit recalibrate every time the hand piece is lift above roughly 95degrees. I got it for about $50 of ebay,
Thanks for that. You've certainly got the old brain box thinking.
An instructions thread would be a great idea. Tips, photo's, tutorials, code, etc..
Cheers
OP
I'd love a 5000cpr, 20000ppr encoder 0.018degree steps ;D one day, easy to swap over. I might start putting some info into a word document over the next week or so.
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Hi daw1zard,
The lever is similar to these, M8 thread http://www.ebay.com.au/itm/281732028352?_trksid=p2055119.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT
I had one lying around and needed a solution to the encoder/mount being in the way of the knob. I drilled a hole down the centre of an M8 bolt and tapped it to 3/16 whitworth from memory. Loctited it into the lever and cut off flush. Removed the spring that went into the existing knob. Was surprised how nice it is to use and am tempted to change the knob to an adjustable lever on the mast clamp.
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Cool idea, I will need to look at getting the fine adjustment upgrade first. Thanks for that.
Troy
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Looks great! Is anyone selling the completed units for a Gemmasta ... if so who and how much?
GR
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You're well and truly an engineering-minded bloke Andrew :)
Ever considered building your own machine from scratch?
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a US Digital E2 encoder, 1250cpr,5000ppr gives me 0.072 degree steps. The encoder also has an index so the unit recalibrate every time the hand piece is lift above roughly 95degrees. I got it for about $50 of ebay,
Thanks for that. You've certainly got the old brain box thinking.
An instructions thread would be a great idea. Tips, photo's, tutorials, code, etc..
Cheers
OP
I'd love a 5000cpr, 20000ppr encoder 0.018degree steps ;D one day, easy to swap over. I might start putting some info into a word document over the next week or so.
I'll probably stick with your proven first. Then complicate things later - can't even find the smiley thingo on here. I'll be using a PICxx microcontroller.
So if there is anybody who wonders how writing software for Arduino's is even possible - like me. There is a god. It's called Flowcode - http://www.matrixtsl.com/flowcode/info/v6_licence_info.php
I think the free license will work for this. All you need to buy is the components and a PIC programmer ($40). I've even found a basic code example that (in theory) should do this job. I shall post an image once internet starts working properly.
Question------. Dismantling that shaft with the big nut. Is there anything I should be aware of. Like a unique rare spring that shoots out, fly's across the room and get sucked up by the vacuum cleaner rendering the Gemasta to the scrap pile? Or a preload that has to be nano newtons perfect? I can rebuild an engine but that makes me nervous.
Cheers
OP
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Ever considered building your own machine from scratch?
I was thinking about doing that Lefty after I decided we couldn't afford a new machine, but then I got myself a nicely priced lightly used Gemmasta for $1000 with some new laps ;D , plus about $120 in bits for the encoder setup. Very happy with my machine atm.
Looks great! Is anyone selling the completed units for a Gemmasta ... if so who and how much?
GR
No, these are just do it yourself projects atm based on the designs in Tom Herbst's faceting book.
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Orange Pirate.
I am going to dismantle my Gemmasta head tomorrow and put the new hollow shaft that I manufactured in. I will take photos as I do it and post them here. MakkyBrown made a replica of the original shaft and drilled it. I made a few minor mods which I hope will make it better.
There's nothing in there that should scare someone who is a bit mechanically minded, its probably worth dismantling and cleaning and regreasing anyway, when I first looked at mine the grease had dried and gone hard so yeah its worth doing.
Paul
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Leah(thanks :) ) has created a"Faceting Machine Modifications" folder upload all pics and documents to that folder. Found in galleries.
http://aussielapidaryforum.com/forum/index.php?action=gallery;cat=86
For reference maybe add part of your username before each photo. ie "Rust-Gemmasta mod pic1" etc and supporting doc. I'll put together a parts list with ebay links etc of what I used and a bit on selecting an encoder. I will see if I can upload a zip of the arduino program code I used. The hardest bit for this build is making the new shaft. It has to be close to perfect so the movement can be transfered into the smaller shaft without a flex point. If you can make the shaft I am happy to help with the rest of the build, machining the shaft is the trickiest bit imo.
Cheers
Andrew
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Orange Pirate.
I am going to dismantle my Gemmasta head tomorrow and put the new hollow shaft that I manufactured in. I will take photos as I do it and post them here. MakkyBrown made a replica of the original shaft and drilled it. I made a few minor mods which I hope will make it better.
There's nothing in there that should scare someone who is a bit mechanically minded, its probably worth dismantling and cleaning and regreasing anyway, when I first looked at mine the grease had dried and gone hard so yeah its worth doing.
Paul
Thanks Paul. Didn't think it would be too hard but better to be prepared.
Cheers
OP
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I have just uploaded some pictures of the build so far, at this location----http://aussielapidaryforum.com/forum/index.php?action=gallery;cat=86 (http://aussielapidaryforum.com/forum/index.php?action=gallery;cat=86)
As Makky Brown mentioned, the shaft is a really precise bit of engineering, both of us took quite a few hours to accurately machine a replacement shaft. It would be possible to drill a small hole down the centre of the existing shaft but both of us were concerned at the likelyhood of breaking a small hardened drill in it and having no wiggle room left at all. This is not a job that you can do with your trusty Black and Decker cordless drill or even a decent drill press, it has to be done in a lathe, very carefully.
It was Makky Browns idea to use the same 1/4" National Fine thread on both ends of the shaft, the big brass front nut and the lock nut underneath it just fit straight back on.
Behind the protractor is the spacer, this is machined from 40mm bearing Nylon and has a 1/4"NF thread to match the new shaft, this replaces the original 1/4"Whitworth brass nut that was on the old shaft, it also is machined out inside to 20mm to house the flexible coupling, three countersunk 3.5mm allen head bolts hold the encoder to the spacer.
The nifty charcoal hammered metal paint look of the spacer is how it came, the nylon has Graphite or Moly or something in it to help it be a slippery bearing and thats how it looks.
I am still contemplating how I attach the thin encoder shaft to the facet head.
So far all this has been achieved without drilling screwing or putting globs of Silicon anywhere near my facet machine.
Paul
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Looks good Rusted. I used dextone metal epoxy(that I've been dopping with) to stick the riser alloy bit to the front and to bed the shaft into the end piece. I first glued the riser in place with cross over piece attached and aligned with the 2.5m shaft loosely in it. I used a tempory brass sleeve to centre the shaft(drilled a 3mm lip into the replacement shaft and had some brass tube) in the recess hole filled with dextone in the front piece. I first filed some gouges/flats on the end of the 2.5mm shaft. I then dextoned it in two steps. First with a small amount into the front bit. The front bit had about a 2.6mm hole furthest in and flared out 7mm cup. After the shaft was set in place I pulled it out(remove the two screws holding the riser to the cross over bit) and filled the cup around the shaft. It is a very solid connection. The only thing I'd do differently is have more of a surface area where the riser glued onto the round alloy face on the faceting machine. I decent bang could remove it but both alloy surfaces were light sanded and perfectly clean so it might be stronger than I think.
I just realized after typing all that it's going to be trickier for you as you need a removable connection/clamp due to your setup on the other side. NO, or a small hole through your mount to get at the grub screw on your coupling to let the 2.5mm shaft come free :). You have probably already thought of that.
Cheers
Andrew
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If this is beyond your capabilities then at least consider upgrading your machine to an electric Depth of Cut meter. For very few dollars you can put together an analogue meter, (with a needle) a battery holder, a linear potentiometer, (variable resistance to adjust the needle deflection) and some wire.
In the Gallery for this thread you can see my meter in the photo of the completed encoder mounting.
I fancied mine up with a couple of banana plugs to make it easier to dismantle when I am cleaning around the machine and a switch,( if you use the original Gemmasta buzzer plug hole underneath the head then park your head in the upright position it can touch the frame and drain your battery.)
(http://aussielapidaryforum.com/forum/gallery/7/medium_32139-210815183728-7559218.jpeg) (http://aussielapidaryforum.com/forum/index.php?action=gallery;sa=view;id=7560)
Edited by admin to add the photo.
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Attaching the lever to the encoder shaft should be easy, just a small grub screw will do that, and to anchor the end to the head, something thin underneath the screw that holds the angle cheater on, or maybe not.
I would like it to be reasonably easy to dismantle for machine maintenance, greasing bearings etc. perhaps the best way would be to drill and tap a small hole so I can bolt an encoder shaft operating lever of some description to the facet head.
Paul
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I tried to upload my PDF on machine tuning to the gallery.but it seems to be picture or video only.
When are you going to make a step by step with photos so we can all have one of these.
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I tried to upload my PDF on machine tuning to the gallery.but it seems to be picture or video only.
When are you going to make a step by step with photos so we can all have one of these.
You can email the pdf to me Tony and I will upload it to downloads section with link to this thread if you like.
I may also be able to modify the gallery to accept pdf files but will have to check later on that (off to tennis shortly).
cheers
Leah
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I tried to upload my PDF on machine tuning to the gallery.but it seems to be picture or video only.
When are you going to make a step by step with photos so we can all have one of these.
I haven't tried uploading documents yet, could you check that Leah?
The tricky bit is the idea of the design has come from a book and anyone building it should buy the book. Tom Herbst(who wrote the book) has his code freely available on his webpage http://www.facetingbook.com (http://www.facetingbook.com) so I don't think it would be an issue uploading my modified code I used but his wiring etc. Although I changed it a bit(but not much as I tried to keep it as similar as possible), the idea is still his and in his book. I can see other tutorials using encoders/lcd etc but to do a full blown tutorial to build it without the need to buy the book is probably not right imo. That said I'm more than happy to help anyone that buys the book and can provide a parts list of exactly what I used so it all works, even happy to modify the program for others. There are a lot of possibilities to develop a heaps better unit, a bigger screen and an ability to read/display cutting steps from gemcad files(probably off a SD card) etc.. I've already started thinking about an upgrade :) .
I might send Tom an email to see what he is happy with being made available in a tutorial
Cheers
Andrew
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I fitted an encoder to a faceting machine years before Toms book. I prefer the E5 myself and have a friend to write the code and fit the LCD screen. You can buy a finished unit from a woodworking company in England. Its a bit too bulky for the Gemmasta's though.
I looked into fitting this to the front of the swingarm. I cut most of my stones at a fixed 41 degrees so I don't need an encoder. If you can get ten people together and buy bulk the encoders are cheaper from US digital.
Its not so much Toms input which is invaluable but its the fitting and machining side that's
invaluable for Gemmasta owners. If you did a PDF giving full acknowledgement too Tom recommending the purchase of his book you should be covered.
Regards Anthony
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I fitted an encoder to a faceting machine years before Toms book. I prefer the E5 myself and have a friend to write the code and fit the LCD screen. You can buy a finished unit from a woodworking company in England. Its a bit too bulky for the Gemmasta's though.
I looked into fitting this to the front of the swingarm. I cut most of my stones at a fixed 41 degrees so I don't need an encoder. If you can get ten people together and buy bulk the encoders are cheaper from US digital.
Its not so much Toms input which is invaluable but its the fitting and machining side that's
invaluable for Gemmasta owners. If you did a PDF giving full acknowledgement too Tom recommending the purchase of his book you should be covered.
Regards Anthony
I prefer the E5 aswell, slightly different to the E2. I was worried about the wire connection on the E2 coming loose but it nice and firm. Even buying 5 units makes them heaps cheaper. I was lucky to find the one I did cheap, hard to find them on ebay with an index and a enough steps. Worth looking on http://www.digikey.com.au/product-search/en/sensors-transducers/encoders/1966131?k=optical%20encoder
Avago encoders would do.
Just working on the rpm code, going to use a hall effect sensor and a small magnet on the underside of the lap just above the belt. Bit hard as the Uno only has two onboard interrupt services and I have to use extra libraries to enable another pin with a software based interrupt. Rusted you should build yours on the mega board and get a bigger enclosure, the mega has extra interrupts available. I tried but my mega board wont fit :( in my box.
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Hi Guys
The Gallery will only accept image and video files so for documents (preferable pdf), will need to use the Downloads system.
But you can then link that file to this thread or any (or all) photos in the relevant gallery album. Or we can add a placeholder image in that gallery and add those links to that description (bit of a workaround but it would work ok once uploaded).
If anyone needs assistance adding to the Downloads, let me know.
cheers
Leah
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Just having a quick look, minimum quantity on these is 1.
Something like this would be nice and MIGHT be suitable, 3 week lead time, orders over $200aud ship free, otherwise shipping is $34. Have to sleeve the small shaft on the build to the 6mm centre of this encoder. Would be heaps cheaper than buying from USDigital.
http://www.digikey.com.au/product-detail/en/AEDM-5810-Z12/516-3253-ND/5357134 (http://www.digikey.com.au/product-detail/en/AEDM-5810-Z12/516-3253-ND/5357134)
Datasheet
http://www.mouser.com/ds/2/38/AV02-4926EN_DS_AEDM-55xx_2015-06-04-706336.pdf (http://www.mouser.com/ds/2/38/AV02-4926EN_DS_AEDM-55xx_2015-06-04-706336.pdf)
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http://www.digikey.com.au/product-detail/en/AEDM-5810-Z06/516-3252-ND/5357133
This one has a 4mm centre didn't come up in the search on therir webpage but found it through google. I have some black plastic nylon tube that perfectly sleeves the 4mm centre to 2.5mm shaft. I will probably endup getting one of the above at some stage. Would workout at 0.018degree steps.
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I've just spent too long stuffing around with #enableinterrupt library ,full of bugs, end result I'm thinking of swapping to a mega board from the uno, the index pulse probably needs to be on an interrupt aswell(currently not) like A and B. So I'm probably going to rewrite the program for the mega, different screen wiring, and bring rpm in through another interrupt. The mega board has lots of extra connections. Also going to put a clock on the screen, any other ideas :) .
I've just broken the belt again on my machine and joining with the heat gun won't work anymore :( , hoping my belt material arrives next week.
Clock module so it's accurate and holds time.
http://www.ebay.com.au/itm/2015-Practical-1X-DS3231-AT24C32-IIC-Real-Time-Clock-Memory-Module-for-Arduino-/281714060248?hash=item4197776bd8
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MakkyBrown,
What changes need to be made to the code to change from the Uno to the Mega apart from renumbering which pins are used?
I have read and reread the chapter in the book and was coming to the conclusion that I should just go straight to the mega.
I have a slightly larger screen in the mail so I was starting to think of uses for the extra screen real estate too.
Until your new belt arrives you could try joining the broken one with whipper snipper cord down the middle and gluing it.
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MakkyBrown,
What changes need to be made to the code to change from the Uno to the Mega apart from renumbering which pins are used?
I have read and reread the chapter in the book and was coming to the conclusion that I should just go straight to the mega.
I have a slightly larger screen in the mail so I was starting to think of uses for the extra screen real estate too.
Until your new belt arrives you could try joining the broken one with whipper snipper cord down the middle and gluing it.
Will you be using a screen from 4D systems? I like the idea of those. If not what is it?
You could dump your favourite faceting designs on the sd card - and it could play you happy birthday too.
One other thought (slightly quirky) I have had is regarding the use of water on the lap. I think the drip system is not good. Especially with the latest polishing laps from gearloose and water loving diamond grit.
A misting system would be good but I can't think of what to use, yet??? But the micro controller could control it together with RPM and temp.
I got my program (v1.1) together today - Mark 1 equivalent. The decimal point almost doubled what I had to do. Nutz.
Cheers
OP
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MakkyBrown,
What changes need to be made to the code to change from the Uno to the Mega apart from renumbering which pins are used?
I have read and reread the chapter in the book and was coming to the conclusion that I should just go straight to the mega.
I have a slightly larger screen in the mail so I was starting to think of uses for the extra screen real estate too.
Until your new belt arrives you could try joining the broken one with whipper snipper cord down the middle and gluing it.
Which screen Rusted, I was looking at those 192x64GLCDs. Definitely go the mega imo. Yes mostly wiring and change a few pin, but I'll probably change the index to being interrupt driven like A and B. Having trouble trying to get the hall effect sensors(magnetic endstops) I have producing a digital signal, might look at some other options for rpm.
And it could play happyday easy orange pirate as I already have a passive buzzer wired in I decided not to use? My screen and most electronics have come off ebay from china. Not sure on water sprayer, have you seen my cabbing machine, all the sprayer are driven with solenoid valves(pics are in my galleries, misc folder).
Cheers
ANdrew
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This would be nice but it's not going to improve my faceting :)
Sainsmart make fairly good boards and it all stacks nice and compact.
http://www.ebay.com.au/itm/SainSmart-Mega2560-R3-7-Inch-LCD-Shield-TFT-LCD-SD-Card-Shield-for-Arduino-/380862655721?hash=item58ad2eece9
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MakkyBrown
This is the screen I ordered, its not huge, but it is cheap.http://lapidarytool.com/cart/index.php (http://lapidarytool.com/cart/index.php)
The interrupt for the Z pin on the encoder was another good reason I saw for using the Mega too.
have a look on that site for sensors, I am sure you will find a hall effect sensor.
Today I am hoping to get the mechanical bits for driving the encoder finished, I will then start on the electronic bit. The programming will be really new ground for me but I think I can see how it all works, quite keen to get it going.
My wifes daughter is expecting another grandchild four days ago, so I am expecting family business is going to be high on my agenda for a bit, who knows how much of this is actually going to happen.
Paul
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I tried to upload my PDF on machine tuning to the gallery.but it seems to be picture or video only.
Tony's Gemmasta Tuning Manual is now available at the Downloads section via this link:
http://aussielapidaryforum.com/forum/index.php?action=downloads;sa=view;down=7
He also supplied a doc on making wax castings - see same downloads category for that one.
cheers
Leah
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I have loaded a couple of new pictures of my build.
After a lot of thinking I made a lever to operate the encoder shaft today, Making it up as I went so its not exactly pretty, plus its made from a lump of waste Aluminium left over from casting some pulleys a while back and full of gas holes, actually its bloody ugly. I could have prettied it up with a coat of paint but this is a build thread so why not warts and all? Paint can come later.
Also a picture of the new protractor lock nut. The old knob will not fit with the encoder and spacer, so a conversion to a lever was the only way, made from Brass this one is pretty, the handle can be unscrewed to allow the lock nut to be removed without dismantling the encoder if I need to dismantle the head for maintenance.
Paul
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You've been busy, good bit of work making those bits.
Looking good.
Cheers
Andrew
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Bit of progress today, swapped over to the mega board, reconfigured the display and written code to display time and rpm. Clock module I purchased has temperature on it aswell so I'll see if I can fit that on the screen too. Tested the hall effect sensor/code for rpm, seems precise and has no problems keeping up with my foredom copy rotory tool out to 20000rpm ;D. Changed the index to an interrupt, but not happy with it, seemed to missed some index events(light didn't flash when passing the index on occasion), probably something simple I did wrong but have decided to be lazy and just put it back how it was.
Anyone not up for the full encoder build and wanting to build a lap rpm display, including a clock if you want, easy to do and cheap :)
Cheers
Andrew
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Here is my latest version. I have added time(code but not working till board arrives) and rpm. When I've finished sorting the time I'm going to leave it as a finished project for a bit. I have decided there is no point uploading faceting diagrams etc as I'm better off using an old tablet to do this.
(http://aussielapidaryforum.com/forum/gallery/7/medium_5704-270815110333.jpeg) (http://aussielapidaryforum.com/forum/index.php?action=gallery;sa=view;id=7571)
This(pic below) is a hall effect magnetic endstop(pinched it out of my 3d printer kit parts). If your wanting to buy one, search on ebay for hall effect arduino, find a similar looking board with sensor on it, might cost $2. Your wanting a board that gives a digital output. These boards have an amplifier on them, when wiring it to the arduino board I put a 10k (pullup, or might be down in this case) resistor between the 5v+ve and the signal(output from sensor) on the arduino board end of connecting cable. You might not need to do this as most arduino boards have a 20k on board pullup resistor. To active it change the line:
pinMode(RPMP, INPUT); to pinMode(RPMP, INPUT_PULLUP);
You will notice I have cut the sensor off the board and put on connecting wires so I could turn over the sensor. Only one side of the sensor will read(larger flatter side) and when you glue on the magnets only one pole of the magnet will trigger the sensor. If you glue them on the wrong way around they won't work(and yes I did this and I was trying to be careful) .
(http://aussielapidaryforum.com/forum/gallery/7/medium_5704-270815103817.jpeg) (http://aussielapidaryforum.com/forum/index.php?action=gallery;sa=view;id=7568)
I glued the sensor to a piece of plastic card to hold it all, I them glue it as pictured above to the alloy mount made out of a bit of 2mm. I glued it with the alloy mount in place so I could align the sensor with the magnets perfectly, I left roughly a 1mm gap. When set I pulled it off, covered it in heat shrink(taking care not to melt bits like the white pin holder).
(http://aussielapidaryforum.com/forum/gallery/7/medium_5704-270815104811.jpeg) (http://aussielapidaryforum.com/forum/index.php?action=gallery;sa=view;id=7570)
I use 4 magnets(might upgrade to eight), they are glued at 90degree intervals, I positioned them by marking a lap above and turning to align to a setpoint below. The 4 magnets give me steps of 15rpm. 8 would give 7.5, 1 would give 60 etc.
(http://aussielapidaryforum.com/forum/gallery/7/medium_5704-270815104644.jpeg) (http://aussielapidaryforum.com/forum/index.php?action=gallery;sa=view;id=7569)
I have bolted the mount on using a slightly longer screw replacing the water bottle holder screws.
Cheers
ANdrew
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Thanks Tony for those pdf's. It's good to have some info like that. Rather that than pay someone to suss it out. :D
Rusted. Great photo's. Just what I needed.
Andrew. That looks great. Clear and easy to read. (http://emoticoner.com/files/emoticons/smileys/partu3-smiley.gif) (http://emoticoner.com)
One thing I don't understand is the RPM set up perhaps because I don't use arduino. Does it not have a timer interrupt? Or is there another reason?
What ever it is. It looks cool.
Cheers
OP
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OP,
Rpm is pretty simple, there are 4 magnets on lap and each time they pass the sensor they change the digital signal being sent to the arduino Mega board. The signal wire is connected to an interrupt capable pin. In this case the signal will drop when the magnet is present. So I use the program line attachinterrupt(interupt circuit number, subroutine to run, FALLING) So every time the signal falls, it triggers the subroutine that adds 1 to a revolutions count. I update the rpm rate every second, so rpm just equals revoultions*15(15 being 60/4 magnetic triggers). After rpm is displayed revolutions are reset to 0 and counted again for the next second. To calculate time allapsed I use the command millis(), which is a running count in milliseconds since the board was turned on.
If you ever want my program let me know as I'm happy to email it to you.
Time, the Arduino mega does have a clock but has no way of holding time if powered off. So the board I'm getting has a more accurate clock plus a battery backup. I have lines in the program I will run to set the time, then deactivate the lines and reupload the program.
Cheers
Andrew
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Thanks for explaining. I use Pic chips from microchip programmed with a graphics based program, flowcode. So didn't understand how the code was working the RPM with the Arduino.
On a Pic I would use a timer interrupt. So when the signal fell it would trigger an interrupt that would start/stop a timer that increments 't' every 0.xx seconds. 60/(txincrement)=RPM.
Cheers
OP
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I will have to have a look at pic chips sometime, flowcode etc. I am fairly new to arduino but it is really good fun getting back into programming after a good couple of decades since I was last programing :). It's great being able to buy all the bit's and make things, wish it was all available 25years ago.
I will have to have a look there might be a timer interrupt for arduino but pretty happy how it's working atm so I'll probably leave it as is.
Cheers
Andrew
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TBH it's only this thread that has got me fired up since my nearly two year old was born. Even now it's a few minutes here and there. So it's good to see what you have done and gives me a bit of inspiration to get back into it. But I think my progress will still be slow. But I will post up when I eventually manage it. ;)
Cheers
OP
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Looking forward to seeing your build OP. If you ever want to swap to arduino it's pretty easy and heaps of info, example programs etc on the web. And parts are very cheap on ebay and aliexpress. Happy to share links to parts/wiring/program.
Was it you that was 3D printing preformer cams? I'm keeping my eye out for a secondhand gemmasta preformer as when I get the printer going I can see no reason why I can't print pretty much any shape. Maybe somehow using the outline from gemcad and smoothing.
Cheers
Andrew
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I posted somewhere about my printed cams. They are only special radius cams for making other special cams for quick calibrated and repeated cutting as well as wax patterns and specialised cabs. I don't make standard cams that are available from Gemmasta.
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Looking at those pics it might have been yours, did you print them yourself?. I'm interested in having a go, but thinking it might be a long term project.
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My friend who designs computer boards and specialty curciut boards drew them and has a file for them. Im getting a printer soon for the prototyping I need to do.
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Were they pretty good straight off the printer or did you have to true up the surfaces?
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It wasn't high resolution but it did the job. The shaft was worn on the performer so I made the centre hole slightly smaller. Im going to rebuild the shaft by building it up with nickel plate and re-machining it. I make my own blanks and have built a cam holder dopstick and facet the corners after making a radius on the three or four sides. By combining the radius cam with the round cam you get a perfect pear shape cam. Im currently building a radius cam milling attachment for my milling machine to do a full range of cams for my opal faceting project. I will do a full PDF when I have it finished. I will also be building by the end of sept. a microsaw for faceting rough and special sintered grinding wheels for cleaning up rough.
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You've certainly got some interesting projects on the go. I'm thinking about taking the faceted outline from gemcad into photoshop and producing a radiused outline from the meet points. Then printing a cam to match. How practical this is time will tell as I don't have a preformer yet or a working 3d printer. I like your idea of a cam holder dop.
Just heading off to Flinders Island for a week, so if I don't respond to any comments on this thread it's because I'm hopefully finding a few nice bits of topaz ;D
Cheers
Andrew
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Finding I can cut to the angle steps fairly accurately. Using the first flicker to a lower angle as the stop. May even be better than depth of cut indicator, but both are working well. Clock module arrived today, might add a timer, have the display flick between current time and timer every couple of seconds and reset the timer by a 10second hold of the function button.
Cheers
Andrew
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Realising the replacement shaft is a major bit of engineering where I have neither equipment or experience and the price of having a shaft made up could get expensive.
Is there any reason I couldn't buy another original shaft and have someone drill down the length of it?
Cheers
OP
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You need a lathe or a mate that has one. I'm not much of a machinist and it took me about 5 hours to make my replacement shaft. I was a case of a little bit at a time to get it absolutely near perfect. I was lucky not to wreak it cutting the threads as the dia I used was very old and blunt. I wouldn't buy a new one as they would probably be stupidly expensive, best bet is just drill your current shaft but do it in a lathe and drill from each side. Your weak point will be the deep coarse thread where the dome nut is.
Or consider doing what I was going to and mount the encoder if front of the large brass nut.
Cheers
Andrew
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You need a lathe or a mate that has one. I'm not much of a machinist and it took me about 5 hours to make my replacement shaft. I was a case of a little bit at a time to get it absolutely near perfect. I was lucky not to wreak it cutting the threads as the dia I used was very old and blunt. I wouldn't buy a new one as they would probably be stupidly expensive, best bet is just drill your current shaft but do it in a lathe and drill from each side. Your weak point will be the deep coarse thread where the dome nut is.
Or consider doing what I was going to and mount the encoder if front of the large brass nut.
Cheers
Andrew
Thanks Andrew.
What I'd done was contact Shell lap supplies and surprisingly the "Pivot Spindle" is a stock item at $66.70 which I'll take any day of the week.
I wasn't sure if there was something aside the drilling I'd over seen that could not be done using the standard part. I agree that coarse thread is concerning. Anyway I shall get a wiggle on and order before they sell out.
Cheers
OP
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That's pretty well priced, basically the only difference between the shaft I made and the original one was the thread where the dome nut is. But if you keep your shaft hole fairly small you should be ok.
Cheers
Andrew
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Thats a good price for the shaft, considering the time spent making one. You will still need to drill the hole in a lathe, don't even contemplate doing it in a drill press (or with your trusty Black and decker cordless). Drilling a 2mm hole of that length you need to be very careful, if the bit breaks in the hole its goodnight encoder mod.
Paul
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Thanks Rusted.
I have been pointed in the direction of a machinist whose business revolves around awkward jobs so I'll let him do that. If I had to get the shaft custom made as well it could of made the price prohibitive. I'll post up that cost once it's done.
Cheers
OP
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It will be a piece of cake for someone with a lathe, a really easy job. You are on your way.
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I ended up with a 2.6mm hole for the 2.5mm shaft,I think Rusted drilled an even larger hole. Given you have a coarse thread I'd go a 2.1-2.2mm(ish) hole for a 2mm shaft. I used a 2.5mm stainless steel welding electrode centre as my shaft, not easy to find shaft material. Try hobby stores for thick piano wire or a welding store/engineering places and they might even give you an electrode(just tap with a hammer lightly to remove the flux coating). I was originally going to use a 2mm shaft but found some nylon tube that was a perfect sleeve from a 2.5mm shaft to the 4mm centre of the encoder I had.
Did you get an encoder? I looked at the Digikey webpage last week as I was thinking about getting a 5000cpr encoder but they have changed it and you can't buy single units in the one I wanted currently. Maybe one day.
Cheers
Andrew
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Just finished research on that. LOL. Ebay has a fair bit - Stainless steel rod. Even down to 1mm, although that would need bushing up to fit. This coarse thread is a concern though.
No encoder yet. TBH the shaft was my concern and I'm not sure on what the final rod size will be. But if my purchase configuration is correct - 5000cpr, index, single ended, default cover and base plus centering tool etc. $105. I can live with that. That's USDigital. Postage will be dear.
Main thing I've been doing is getting to grips with coding the glcd. Making life hard for myself but I like the challenge. A bit over kill but I've had it lying around for a while. Apart from all the bells and whistles it only has 5 wires to run it.
But as I have a lot to learn with the coding on that I may start off with a 16X4 LCD. The program for that has been roughly drawn up.
I'm not the fastest operator around. Get's me out of things like washing up though. The wife finds it harder to watch me take 3 hrs to do some dishes than it is for me to do them. LOL.
Cheers
OP
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Seeing that you can get the replacement shaft if something goes wrong (breaking the drill in the hole) why don't you just take the shaft from your machine shaft to the machine shop and get it drilled? If you ever decide to go back to standard the hole in the shaft is really of no consequence.
Paul
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OP,
If your putting in a US Digital order let me know how much the postage cost is, if it's expensive and it's ok with you I'd consider getting another wheel and reader to suit my housing and split postage with you.
With a 5000cpr(20000ppr) encoder you might need to write some smoothing routines based on lap rpm to stop flicker only if it's too bad. I'd also consider not worrying about a depth of cut circuit as I've pretty much stopped using mine and the first flicker to a new angle is proving to be very accurate.
Cheers
Andrew
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@ Rusted.
Very true. I'd just feel better having a pivot ready to go. It's a psychological thing.
@ Andrew.
No problem. I'll let you know. But I really am Captain slow.
Thanks for the pointing out the cpr to ppr. I'd forgotten it was backwards. What is your opinion for a good balance of accuracy and simplicity?
Flicker stabilisation. Do you think grabbing say ten sample measurements, take an average and up date screen every 1/2 second work?????
Interesting about the DOCI. I'll leave that out. Thinking about it. It makes sense the encoder should be more than up to the job for accuracy.
And the RPM measurement useful, or gimmicky??? I'll still put it on either way.
Cheers
OP
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@ Rusted.
Very true. I'd just feel better having a pivot ready to go. It's a psychological thing.
@ Andrew.
No problem. I'll let you know. But I really am Captain slow.
Thanks for the pointing out the cpr to ppr. I'd forgotten it was backwards. What is your opinion for a good balance of accuracy and simplicity?
Flicker stabilisation. Do you think grabbing say ten sample measurements, take an average and up date screen every 1/2 second work? ??? ?
Interesting about the DOCI. I'll leave that out. Thinking about it. It makes sense the encoder should be more than up to the job for accuracy.
And the RPM measurement useful, or gimmicky??? I'll still put it on either way.
Cheers
OP
What I've got is probably good enough(1250cpr,5000ppr) but a bit more would be nice and if I was upgrading I was thinking why not go with 5000cpr,20000ppr ;D
If your not in a rush I have got some detailed searches setup on ebay to target suitable encoders and will let you know if something comes up above 1000cpr(I wouldn't go any lower). I suspect it will cost over $200 from usdigital for an encoder due to the high au$ etc. Rusted encoder was cheap, an could be worth getting one of those if it's 2000cpr not ppr. Just need Rusted to get it going to let you know.
Flicker stabilization I'd wait and see if it's a problem, my setup is fine atm, but I wonder what would happen if the lap surface is out more than a step. Is a 5000cpr encoder accurate enough to cause this I'm not sure. Is it too accurate to be not worth getting I'm not sure :). I'd confidently say 2500cpr would be good and flicker wouldn't be an issue. I also wonder if smoothing could reduce the accuracy(repeatability) of using the angle as a stop.
Very important to get an encoder with an index so you can recalibrate every time the hand piece is lifted, I have found this useful combating electrical interference at off/on and super high lap rpm.
DOCI, I'm finding it is useful as an early warning system before the angle in triggered but I'd probably not bother. Although my setup only has 0.072degree steps I'm finding the point of hitting a new step is super accurate and repeatable.
RPM, is interesting and I suspect I'll find it more useful over time. My machine has low and high speeds so it's hard to gauge rpm from motor noise etc. I was also thinking I might be able to use it as a factor when smoothing any angle flicker, but after typing this I'm wondering if a 5000cpr encoder is too accurate and smoothing if needed could cause issues with repeatability.
Hope that help a bit and doesn't confuse too much.
Cheers
Andrew
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I'll refresh my trigonometry over the w/end and setup a spread sheet to relate lap oscillation to angle change to see if it helps in relation to selecting an encoder.
Cheers
Andrew
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At the moment I am attempting to get my head around the programming, I have a contact that would be happy to help but I would probably end up with everything working and no idea why or how. So, at the moment, slow and probably lots of mistakes along the way, if I get myself completely stuck then I can get a bit of assistance.
Interesting what you are saying about the depth of cut indicator, I wondered why it was there. Either way its easy to leave out or put in.
Paul
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If you are worried about jitter with a high resolution encoder, just lengthen the Sample/Hold rate.
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Just been having a look. @OP
A 4500cpr or 3600cpr encoder could be good. If you got a 4500cpr you would only need to display 2 decimal places, 3600cpr 0.025degree steps so all major angles would be displayed as even numbers.
Found this one on ebay, would need to make sure the ribbon cable can be easily changed(as cables will break over time) and you can read the line driver output.
http://www.ebay.com.au/itm/HOUSED-ENCODER-3-CH-3600CPR-8MM-HUB-MPN-HEDR-55L2-BY09-AVAGO-TECHNOLOGIES-/390869081371?hash=item5b019cdd1b (http://www.ebay.com.au/itm/HOUSED-ENCODER-3-CH-3600CPR-8MM-HUB-MPN-HEDR-55L2-BY09-AVAGO-TECHNOLOGIES-/390869081371?hash=item5b019cdd1b)
http://www.avagotech.com/docs/AV02-3823EN (http://www.avagotech.com/docs/AV02-3823EN)
Rusted is your encoder a line driver output ? If it is, excuse my limit electrical knowledge, it looks like a,b and i(z) could need to be wired with pullup resistors to 5v. Or, as ebay encoder above and your encoder has the A-,A,B-,B, Z-,Z it might mean it can be wired Push/Pull as in the below link. Could be good to reduce interference.
http://digital.ni.com/public.nsf/allkb/0C5091E9099059BC86256FC1007947AA (http://digital.ni.com/public.nsf/allkb/0C5091E9099059BC86256FC1007947AA)
Cheers
Andrew
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If you are worried about jitter with a high resolution encoder, just lengthen the Sample/Hold rate.
Hi Gearloose,
Just wondering what you used on the machines you built to measure angles? What was the accuracy like?
Cheers
Andrew
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Hey Andrew.
Thanks very much for all that time and effort. Much appreciated. I agree with the 4500cpr 0.02 is nice and round.
I think I'll stick with USdigital. For the difference I can get exactly what I want with the alignment tools etc.
Still haven't heard any more about the pivot/shaft. :/
Making progress on software.
I'll try and get pics up today. Albeit concept and a bit showy graphics as I'm still figuring it all out.
Cheers
OP
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Got the hard bit done. Communicating with screen.
The circuit is mostly done. Using a pot as a stand in encoder. The pot is the signal source for the gauge and top LED digits.
It doesn't have a hall effect for rpm yet but that shouldn't be a drama.
LED is in the circuit to check clock speed and programming.
The key pad is giving me some thinking.
The microcontroller is a bit like using a canon to kill a fly. But that's all I got at the mo.
Anyway a kinda working very tacky screen and circuit.
(http://aussielapidaryforum.com/forum/gallery/7/7740-280915151000.jpeg)
(http://aussielapidaryforum.com/forum/gallery/7/7740-280915150731.jpeg)
Cheers
OP
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Looking good OP, nice big screen beers .
I put an order in with Shell-Lap last week and haven't heard anything either.
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I put an order in with Shell-Lap last week and haven't heard anything either.
They can be slow if the item is not actually in stock - keep hassling them so your order stays top of the pile.
You will get the stuff but allow more time than you thought.
cheers
Leah
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I put an order in with Shell-Lap last week and haven't heard anything either.
They can be slow if the item is not actually in stock - keep hassling them so your order stays top of the pile.
You will get the stuff but allow more time than you thought.
cheers
Leah
I sent an email enqiring if any of the items were slowing the order and my order was shipped the next day. :)
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Some progress. My spindle arrived on Friday. And today I got it drilled. The shaft is a piece of stainless welding rod, about 2.4mm. The drill size used I'm unsure (thought it was a 2.1 mm but obviously not). But the tolerance is very tight. I had to find a straight section in the new straight rod and then spend a couple of hours lapping them together to lose the drag. Now like bearing surfaces.
The part number of the spindle is GM2053960 and cost is $66.70 incl. Drilling and shaft was free.
Finally making better progress with software, although still in roughing out stage. Only this morning I finally got the touch screen number pad, slash menu working. I'm sure a proper programmer would manage it in half a day. But I have spent the last four weeks in denial about "stack corruption
" warnings...... Exactly. Still needs work :)
(http://aussielapidaryforum.com/forum/gallery/7/medium_7740-201015192502.jpeg) (http://aussielapidaryforum.com/forum/index.php?action=gallery;sa=view;id=7697)
Cheers
OP
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Looking good. :) Your new shaft from shell lap looks to be thicker on the bearing side and no silicone sleeve(unless I can't see it). Should be stronger.
Cheers
Andrew
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Looking good. :) Your new shaft from shell lap looks to be thicker on the bearing side and no silicone sleeve(unless I can't see it). Should be stronger.
Cheers
Andrew
Ahhh. That explains the product description:
GM2053960 BANJO PIVOT SPINDLE (NO INSULATION)
I guess that is for the soft stop/light indicator (http://emoticoner.com/files/emoticons/smileys/dont-no-smiley.gif) (http://emoticoner.com) . Which will now become my new power supply.
Cheers
OP
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Yes it was to isolate the handpiece and not needed. I'm about to pull all the depth of cut wiring off mine as I'm not using the meter at all. It is not as accurate as the encoder imo, and it lets me adjust the fine angle knob when cutting. I'm setting the angle basically as a support then starting cutting at roughly the angle then back off the fine angle adjust so all the handpiece weight is pushing the stone on to the lap even near the desired angle. Helps with accuracy and repeatability of using the transition to a new angle on the encoder as my stop.
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I thought I'd give an update on progress so far.
Most of this is repeating what Andrew had done. But another description always helps.
I made a riser from a gearbox cross member using an angle grinder and a dremel which I glued to the quill this is connected again ,using epoxy glue to a stainless steel shaft (welding rod) that run through the pivot bolt. I had this drilled by an engineering mate on his lath.
(http://aussielapidaryforum.com/forum/gallery/7/medium_7740-160116193811.jpeg) (http://aussielapidaryforum.com/forum/index.php?action=gallery;sa=view;id=7842)
The other end of the shaft connects to the optical rotary encoder.
The encoder is mounted on an aluminium spacer that I had machined up, this also replaces the brass domed nut that holds the pivot bolt in position.
(http://aussielapidaryforum.com/forum/gallery/7/medium_7740-160116194150.jpeg) (http://aussielapidaryforum.com/forum/index.php?action=gallery;sa=view;id=7843)
I also had to replace the angle locking knob using exactly the same handle as Andrew had and it does work beautifully. Again I had a mate drill an M8 bolt on his lath so it could be adapted to fit. It should be pointed out that one of the benefits of using this handle is that it can be moved into any position without affecting the clamping tension holding the angle.
(http://aussielapidaryforum.com/forum/gallery/7/medium_7740-160116194407.jpeg) (http://aussielapidaryforum.com/forum/index.php?action=gallery;sa=view;id=7844)
The encoder I chose is 4000 counts. In other words marks off every 0.0225*. Not a perfect number but... I can work with that.
Also because Andrew mentioned he had a few interference problems that needing a bit of a touch up in design I was concerned that there may be a slim possibility that I could have a worse problem that would become a headache so I opted to buy the differential option, which from my years specialising in auto diagnostics is perfect for dealing with noise. At $20 more, I thought was worth the extra money.
The encoder is then connected to the circuit board where the first component is a chip that converts the differential signal to a single ended one which then the micro processor does the business of doing the maths and calculations and sends the data to the screen using a rs232 protocol.
(http://aussielapidaryforum.com/forum/gallery/7/medium_7740-160116194640.jpeg) (http://aussielapidaryforum.com/forum/index.php?action=gallery;sa=view;id=7845)
Unfortunately I outsmarted myself here with the programming and chip choice. I tried to use a small microprocessor and a technique called polling. Where the processor regularly checks to see if the input from encode via the other chip is on or off then does the maths and sends the info to the display. The trouble was while the chip was busy sending the data to the display, it didn't bother looking at and counting the switch's This resulted in poor accuracy. It didn't work.
So I'm rebuilding the board, using a bigger processor with more options and can be clocked significantly faster and use interrupt routines instead where the program reacts as soon as an event occurs.
But basically this is progress update. The challenge has not been abandoned.
Cheers
OP
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Getting there OP ;D Those racketing handle work well, I was thinking about using one on my mast knob but haven't got around to it. Very impressed with your electronics skills/understanding. Looking forward to seeing it finished. I'd go the differential option if I made another, I think rusted's encoder is differential aswell.
Hows CI?
Cheers
Andrew
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Thanks Andrew. Yep, it's starting to look like it's going to happen. Just got to finish off the hardware and do the software. And those handle's are way better than I imagined and sturdy with it.
My electronics aren't that great - version one is proof of that :) . And if you can do the arduino, you can do the rest. The data sheets tell you how to bolt it all together. And what's not there is on google.
Although I do own a fast oscilloscope for work which is handy for fault finding.
What's Rusted encoder part number? Is it still having teething problems?
If it is differential I think it would work as single ended (that is where a scope comes in handy). But it would just as easy to use it as a differential. But he will need a line receiver the same as I have used. If he wants I can send one out (They came in a pack of five).
We just arrived last Friday, 8th after a mad couple of months. And got the packed boxes during the week. It's very relaxed here and the people are really friendly. The scenery is just amazing.
The kids are struggling with the humidity a bit but the house we got is fully air conditioned with free, yes free, electricity. Still no rain yet, but I'm sure it will come.
Can't wait to get cutting again. :)
cheers
OP
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Not so much teething problems as lack of programming experience, I have put it aside for a bit, but will get back to it as soon as I have evicted the termites from my bathroom.
I started doing the kitchen, which joins onto the laundry, while retiling the laundry, I discovered some hungry little horrors eating my bathroom out from under me, slowly getting there, but I want to be sure they have gone before I close everything up again.
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Hi Rusted,
Have you got it wired up? Screen going etc, if you want you can post it to me and I'll see if I can get the program going for you.
Cheers
Andrew
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Thanks for that offer Makkybrown.
I haven't really had a good play with the thing for quite a while, the display was what was stopping me and I couldn't get past that, I just had so much on my plate that the encoder just went onto the backburner.
This year I didn't put my hand up to be the President of the Gem Club so I am looking forward to a bit of time to do my own things.
1. Get encoder going.
2. Cut some stones.
3. Go fossicking.
Paul.
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What's Rusted encoder part number? Is it still having teething problems?
If it is differential I think it would work as single ended (that is where a scope comes in handy). But it would just as easy to use it as a differential. But he will need a line receiver the same as I have used. If he wants I can send one out (They came in a pack of five)
OP,
You'd better have a look at Rusted encoder.
https://www.ia.omron.com/product/item/2391/
I didn't realize you could get line receivers and haven't read what they exactly are/do.
I was thinking he could wire his encoder in a push/pull arrangement or just on the +ve wires.
Paul,
Sounds like you have a great year planned.
Cheers
Andrew
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What's Rusted encoder part number? Is it still having teething problems?
If it is differential I think it would work as single ended (that is where a scope comes in handy). But it would just as easy to use it as a differential. But he will need a line receiver the same as I have used. If he wants I can send one out (They came in a pack of five)
OP,
You'd better have a look at Rusted encoder.
https://www.ia.omron.com/product/item/2391/
I didn't realize you could get line receivers and haven't read what they exactly are/do.
I was thinking he could wire his encoder in a push/pull arrangement or just on the +ve wires.
Paul,
Sounds like you have a great year planned.
Cheers
Andrew
Definitely differential. You may be able to connect it single ended by just using the A, B and Z but I can't be sure. If have access to a scope that would help.
But may as well make most of the differential option to remove problems of interference. It's basically how they transfer data signals around noisy environment's like automotive (CAN Bus). They take the initial encoder output and puts it through a chip called a line driver that split's into two signals, high and low/inverted (A and A-) So what happens on one wire, happens on the other but the difference remains the same. So when it's converted back to a single output by the line receiver, it's perfect. That's about all I know and probably not entirely correct.
The line receivers are cheap but I had to buy a min of 5 (am26c32). So I have a few spare. PM me an address and I can send one over with an IC socket. You will still need some resistors (X3 + 1) and capacitors (X3 + 1) (can't remember the value's I used ,theoretically is different for each project, but can PM that)
cheers
OP
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This project of mine is cursed.
Finally, finally got it working after 9 months. The problem I had was I programmed the chip to interrupt on an input that wasn't connect. So every time interference occurred it would miss counts
SO it was sorted. Nice big screen, big numbers. The rpm counter was working. It was a piece of art.
So where are the pics. Well I had it all assembled and mounted in a nice plastic box. Connected it up and 'POP!". The short story is a mounting screw, or point (unsure) touched the back of the board and shorted the 12V rail to the 5V. Complete destruction.
Now I'm just pacing in complete disbelief. Aaaaahhhhhhh...................................
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What a cow of a thing to happen. :o :o
Hope you recover soon.
Are you going to start again?
Could have been worse. Saw a utube video recently of a SUV that combusted because they had a generator running next to a kero lamp in the back of the vehicle. ::) First time campers near Uluru. At least their caravan did not burn.
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What a cow of a thing to happen. :o :o
Hope you recover soon.
Are you going to start again?
Could have been worse. Saw a utube video recently of a SUV that combusted because they had a generator running next to a kero lamp in the back of the vehicle. ::) First time campers near Uluru. At least their caravan did not burn.
So do I. Other wise my head is going to fall off from all the shaking in disbelief I'm doing. :)
I'm going to have to Jerry. It's not the amount of money that went up in magic smoke. It's the research. Being a complete novice I have to start again figuring out all the component values and the circuit design was done on the fly. So no diagram either. Boo hoo!
On the bright side. Mk 3 will be bigger, brighter and faster. With added circuit protection. :D
I wonder if the sunset on the rock had an extra special strange flickering look to it that evening
Cheers
OP
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This project of mine is cursed.
Finally, finally got it working after 9 months. The problem I had was I programmed the chip to interrupt on an input that wasn't connect. So every time interference occurred it would miss counts
SO it was sorted. Nice big screen, big numbers. The rpm counter was working. It was a piece of art.
So where are the pics. Well I had it all assembled and mounted in a nice plastic box. Connected it up and 'POP!". The short story is a mounting screw, or point (unsure) touched the back of the board and shorted the 12V rail to the 5V. Complete destruction.
Now I'm just pacing in complete disbelief. Aaaaahhhhhhh...................................
Bugger, is your encoder ok? It's so easy to do, we been collecting a few blown up components on my sons robots lately. I connected a voltage regulator up with reverse polarity and it went off like a fire cracker. You could always swap to ardunio and I'll give you all my code, I'm about to pull the mega out of mine and put in a pro-mini, they are only $2 from china and should do the job.
Don't give up.
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Unfortunately complete destruction from that one tiny over sight. The only thing I worth saving was the heat sink for the regulator. The graphics program for the screen and the encoder program are both on the lappy. I still have heaps of spare micro-controllers. The next board I'll solder in a zener diode and fuse. But thanks for the offer. The PIC I'm using has so much interrupt capabilities, it's perfect for the job.
Definitely not giving up. It was looking and working nice. Big bold inch high yellow digits on a black background, immediate update. Just some work on the screen graphics to do.
Must admit I am balking at the thought of buying another encoder. It's bad enough seeing the price in merican $'s without the postage. :o
Cheers
OP
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You might be able to just get a new reader for the encoder which will save a bit or did it all melt :( . Taking interrupts, we are using a library for ardunio that opens up heaps of extra interrupt pins. The robots have 19 interupts running each. All measuring pulse lengths from various sensors.
I think even on a small pro-mini you can activate most pins as interupts.
Encoders, you might be able to get an Avago? spelling one cheaper. Could be worth having a look on Aliexpress, something might have appeared. I've also had some success with some of the larger Chinese ebay sellers getting me things they don't stock. GC Supermarket is good.
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No melt down. Death was silent but violent except for the exploding cap and a glowing red hot component on the display.
I've been checking out these Atmel chips. I like the idea of interrupt capabilities on all pins. But I like the range of PIC more. Even if I went to Atmel , just not an arduino fan, each to their own though ;) - just to much extra bulk, the board and the boot loader. I originally started with Picaxe , which is a Pic with a boot loader. But after using 'Flowcode', programming is just way too easy.
As for a replacement encoder, I'm just going to bite the bullet and buy another US digital. Although I did have a quick look around for a replacement, if I procrastinate too much it won't happen. Although finding somewhere up here that has a Fax (US Digital is order by Fax) that has capabilities outside Queensland seems to be the hurdle at the moment.
I also had a look at that GC Supermarket. Good gear on there.
The replacement screen has already arrived and the replacement board should arrive early next week. Version III is a go.
Cheers
OP
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I think I've just joined the blownup encoder club :'( , I think I plugged the encoder to display unit cord plug back to front. Mega is dead, just had got it working again. Hoping the encoder reader is ok but I don't like my chances. Have you ordered replacement encoder OP?
Will assess it tomorrow :(
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That is not good MakkyB. I feel your pain. Welcome to the club you didn't want to join. ;)
You may be OK. I noticed some stuff is polarity protected. I ordered my encoder weeks ago before I started to procrastinate although I have avoided looking at the invoice. :-X
I have my circuit built, display running and the RPM side working. But because of my last disaster, I'm adding a 'crowbar' circuit to avoid anything over 5.2V and a diode for reverse protection before the encoder gets plugged in again. Lesson learned. I'm waiting for parts.
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I think I might have been a bit lucky. Put in a new mega and atleast the screen goes. Have removed the depth of cut code and found a simple library for the clock so it now has the time. The big test will be when I test the encoder tomorrow.
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;D ;D ;D ;D Fixed ;D ;D ;D ;D
(http://aussielapidaryforum.com/forum/gallery/8/medium_5704-100916113333.jpeg) (http://aussielapidaryforum.com/forum/index.php?action=gallery;sa=view;id=8257)
Removed DOC and got the clock going. Clock was really easy as a new library had appeared since I was last looking at it.
Something is still not quite right when I turn it on sometimes as the screen doesn't go. I think the screen might be a bit faulty, but atm it's going and usable and I didn't blowup the encoder reader :) I might look to getting a different screen, preferably one with a serial interface to get rid of all the wires. Looking at my/Toms encoder code again, gee it's straight forward after helping my son build/program his robots.
Looking at the screen pic again I should add the date and it would only be adding/changing a line or two of code. Great little clock module, only about $1 off ebay. I found a simple but powerful library to use with it. It has a small battery so the time isn't lost when the encoder unit is turned off. Would be easy to make a stop watch so you can time how long it takes to cut a stone.
Cheers
Andrew
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Looks like club membership just halved :'( :) . And you answered a question I had about the clock. Something I've been pondering. I bought a heap of those Real Time Clock modules before and couldn't get them to work.
I've been looking at screens from 'Nextion'. A 2.5" is $13. A 3.2" $20. The GUI is not so hot as 4D systems but for $20 you can't go wrong. There is also loads of Arduino software out there for them, unfortunately nothing for Microchip and it's not open source software so....... But I still bought one. Serial data is the way to go.
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Yeah I was pretty happy ;D , thought I had blown it up but lucky it was just the mega that died and they are only about $12.
The screen I'm using is about 3inch usable area but the pixels are pretty chunky. 128x64. Might have a look on ebay to see if I can find one about the same size so I can use the same enclousure.
The clock I used was dead easy, vcc,gnd and the two i2c wires. Included the library and pretty much just copied/changed a few lines of code and it was done.
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Those nextion screens look pretty good where did you buy them from?
There is this cheap one on ebay but I wonder if it's a dodgy seller.
http://www.ebay.com.au/itm/3-5-Nextion-HMI-TFT-LCD-Display-Module-For-Raspberry-Pi-2-A-B-Arduino-Kits-/152236980404?hash=item237207f8b4:g:bnYAAOSwFdtX1ECG
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I bought it direct from Nextion. The price works out the same as ebay by the time postage is applied and I also bought the the USB to UART converter for $6. I don't no if it is necessary, it is on the 4D systems screens along with the SD card. I've a feeling you can program the Nextion screen with SD only but it makes debugging way easier with the converter.
Cheers
Op
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FINISHED ;D ;D ;D ;D hotthirsty
(http://aussielapidaryforum.com/forum/gallery/8/medium_7740-240117143540.jpeg) (http://aussielapidaryforum.com/forum/index.php?action=gallery;sa=view;id=8469)
The board showing the micro controller (big chip at 9 o'clock) The tricoloured LED (the bright one). The encoder connector at 12 O'clock. The micro controller programming cable below that. RPM counter connector centre and at the bottom the ribbon cable to connect the scree. The whole of the bottom right corner is a power supply circuit including a 5V regulator (12V to 5V), a diode to prevent reverse polarity stuff ups, a crow bar circuit (including the little chip) and a quick blow fuse to avoid over voltage situations - again. At two o'clock is the chip that converts the differential signal from the encoder to a single ended signal for the micro controller. This was used to stop the effect of electrical noise causing problems. But knowing what I now know I would consider taking another, cheaper approach.
(http://aussielapidaryforum.com/forum/gallery/8/medium_7740-240117143438.jpeg) (http://aussielapidaryforum.com/forum/index.php?action=gallery;sa=view;id=8468)
(http://aussielapidaryforum.com/forum/gallery/8/medium_7740-240117143626.jpeg) (http://aussielapidaryforum.com/forum/index.php?action=gallery;sa=view;id=8470)
Finally finished. And it works way better than anticipated. A long time getting here. When version’s three smoke escaped, it meant reordering everything with almost every order went astray. Also, because I had been doing the design on the fly, it meant I had to reinvent it the circuit again.
Also since the smoke had escaped once I had no intention of letting it happen again, so I added a failsafe circuit (crowbar circuit) as well. Being pretty clue less about electronics meant it all went at a snail’s pace.
Also, added a tri-coloured LED that turns on and off depending on what the encoder is doing. A sort of diagnostic tool as I found in previous builds not knowing what the processor was seeing was always a problem when debugging. And it looks cool too.
The encoder has a resolution of 0.0225* .The screen is a touch screen which displays the actual angle as well as the target angle, it also shows RPM numerically as well as graphically and is accurate to +/-3 RPM from 10 – 2000+ RPM. I aim to have a keyboard on it to at least put in the target angle. Once the actual angle approaches the target angle the screen will change colour, this is so I don’t have keep checking the figure and as long as it’s in my peripheral vision I’ll know when the cut is near done. A kind of ‘Cut to Depth Indicator’ I guess. The yellow wire is a switch wire from the screen to the microcontroller to signal a mode change. The better way to do it would have been through serial data but my programming abilities are a bit to basic.
So far, I a very impressed by its performance and hopefully it will make angle adjustment a lot quicker, certainly easier on the eye, and repeatability should be many times more accurate. My only complaint is my graphics design is a bit rudimentary slash crap, if I was a bit artier it could look really cool also. But this can all be played with and adjusted a bit further down the road.
I have to say a big thanks again to Makkybrown as without his designs and idea’s this would never of happened. It’s been a great learning curve also. I’m looking forwards to my test cuts to see what it can produce.
Cheers
OP
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Congrats OP beers ,
When I cut with mine, I cut until the target angle I want is constant no flicker. The last bit when it's almost showing the target angle constantly I'll let the stone run on the lap with no hand pressure till target angle is constant. This works really well for me.
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And another successful Encoder build... This time on a Halls Xtra. Detailed by Tom Herbst in his Faceting Book, and with the genorous
help of Makky Brown who adapted his code to suit updated components, I started the build a little after Xmas.
A little bit fiddly, but within the reach of anyone who has the patience and the drive to cut a good stone.
Makky B was generous with his help and sugested I use the same components as his build which made the puzzle easyer to
nut out.
I have to say that I am delighted with the result...You've heard it all before if you have been following this thread,
speed, acuracy, repeatablity, etc... Its a quantun leap from the bog standard Xtra. I've even got a clock (for assessing
temporal distance between tea brakes) and an RPM Counter.
Main parts from Ebay and US digital and the rest from Jaycar, fitting the encoder to the machine requires a little thought
though I suspect its easier than on the Gemmaster.
Eternally great full to MB ...he gave me everything I asked for...albeit NOT on a silver platter... I had to sort the puzzle...a great learning curve.
But thats OK! I had to read the program a hundred times, make a circuit diagram and parts list to make sense of it all...a bonus! and in the spirit of the help
that came my way from others, I'm more than happy to share the experience of my build. Don't be scared of it... its not that
difficult... others have done the hard yards and you WILL be happy with the result.
Q
PS First time on a forum, i've attached the pics in a PDF file ...Hope it works
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great work Quentin and shows the power of the community in forums such as these.
Can I suggest you post your photos in the Gallery - there is a relevant album for stuff like this (Faceting Machine Modifications):
http://aussielapidaryforum.com/forum/index.php?action=gallery;cat=86
If you do it as a pdf attachment, it runs the risk of being deleted as the attachments folder fills up.
Cheers
Leah
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Well done Quentin and welcome to the forum, the xtra looks like a nice solid machine. It also looks a lot easier to fit an encoder than the gemmasta. Thanks for uploading the pics etc.
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Very cool Quintin. beers Well done. Can I ask a few questions? Whats the controls on the display do? What sort of encoder did you settle for? And one more, which I should ask Andrew as well. How do you enter the 'target angle'?
With both you and Andrew having real time clocks fitted and having a third decimal place. I can feel an update coming. ;D ;D
Cheers
OP
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The target angle is entered pushing/hold the button when at the desired angle but it's useless imo as I never use it. You use the same button to access the second screen which stores your last 10 target angles. Or did I change it to 12, it been that long since I used it I can't rememer lol.
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Hi OP,
Ended up using an E5 Encoder from US Digital 2000 CPR.I too had noise from the DC motor but fixed it with an external plug pack. The switch just isolates the encoder and the knob is the speed controller mounted in the same box (hence the noise) All good however.
Must say that i'm impressed with your build. Love the colour screen.
Q
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Thanks Quentin. That's interesting what you have mentioned about the noise. As you probably know MakkyBrown had the same problem. I've yet to complete a proper run with mine but it makes me think the differential option I chose for the encoder may have been the right choice.
The colour screen was easier than it looks. In the screen GUI (graphics user interface) software just cut and paste images or numbers. Manipulate them, chose a colour and assign a number. Then with the micro-controller, using that GUI, it was just a case of sending value X to screen item Y.
Literally as easy as that.
Cheers
OP
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My noise is probably gone now, removing the DOC circuit and wires fixed it. I should pull of the last couple of ferret magnets and test it.
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I've got my encoder turned on all the time atm as the screen is playing up and it doesn't like cold starts so...
I've just ordered a new screen. Same size as the old one but I can wire it in serial to get rid of the wires birds nest. And cheap only about $7 delivered :) No need for a mega now will use a nano with connector shield.
http://www.ebay.com.au/itm/ST7920-128x64-12864-LCD-Display-Green-Backlight-Parallel-Serial-Port-for-Arduino-/191981783250?hash=item2cb30188d2:g:A6oAAOSwiDFYNYe0 (http://www.ebay.com.au/itm/ST7920-128x64-12864-LCD-Display-Green-Backlight-Parallel-Serial-Port-for-Arduino-/191981783250?hash=item2cb30188d2:g:A6oAAOSwiDFYNYe0)
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Hi MakkyBrown
Did you ever get the serial screen to work with the "nano" it would certainly tidy the whole encoder project up.
I was thinking of rebuilding mine...Need to get rid of the "rats nest"
Regards Quentin
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Not yet, upgraded to 5000cpr but working ok so haven't. (new power supply sorted the screen not starting problem). Email sent with info that might help.
MB
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Hey guys, I've been reading tom herbsts book and I'm looking at doing the encoder mod to my halls xtra. Any hints and tips before i start buying all the parts. Think I'm going to go the us digital E5 encoder cpr 5000 just not sure on the bore, base packing options
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Hey guys, I've been reading tom herbsts book and I'm looking at doing the encoder mod to my halls xtra. Any hints and tips before i start buying all the parts. Think I'm going to go the us digital E5 encoder cpr 5000 just not sure on the bore, base packing options
Digikey has free shipping over $60aud. The clip-on ones are good but I wouldn't want to be pulling them off/on frequently if at all. The others might need a line receiver, you'll have to check the model number for what they actually are. Use a serial screen, don't bother with doc, target angle, or second screen. Add rpm. Put an emi filter on faceting machine and use decoupling capacitors + ferite magnets on encoder box/cables. Don't bother using the same screen library or fonts as Tom, way out of date.
https://www.digikey.com.au/products/en/sensors-transducers/encoders/507?k=encoder&k=&pkeyword=encoder&pv395=48&FV=fffc0204%2C6240001%2Cffe001fb%2Ca4019b&mnonly=0&ColumnSort=0&page=1&stock=1&quantity=0&ptm=0&fid=0&pageSize=25 (https://www.digikey.com.au/products/en/sensors-transducers/encoders/507?k=encoder&k=&pkeyword=encoder&pv395=48&FV=fffc0204%2C6240001%2Cffe001fb%2Ca4019b&mnonly=0&ColumnSort=0&page=1&stock=1&quantity=0&ptm=0&fid=0&pageSize=25)
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I know this is a bit late...i haven't been on this forum for some.
I have done the encoder trick on the hall Xtra and on the gemmasta. Got the details if you need a hand.
Quentin
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Quentin,
I have started the journey. Any help would be appreciated with 1) the programming and 2) getting a new arbor machined. This I will need to out source as I do not have access to a lathe.
Thanks in advance.
Marcus
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I will post some more information of where I am up to when I get home. I am using an arduino as the main platform.
Marcus.
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Welcome Marcusfri, happy to help. :)
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Hi Makky, I haven't gone down the path of digitising my machine yet, since the Facetron has dial up angles, I haven't been bothered as I have printed a 1/100th scale that works ok.
But I am thinking of making a tacco for the lap speed. As my machine's speed seems way faster than most. Minimum speed is about 60 to 100 rpm. I am not sure if I am exceeding the maximum RPM on some of my laps.
How did you implement the RPM counter on your conversion?
Have you found it useful?
The alternative is to use a strobe to measure/check lap speed at the dial settings and mark the position of the maximum lap speeds on my dial.
regards
Flash
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Hi Makky, I haven't gone down the path of digitising my machine yet, since the Facetron has dial up angles, I haven't been bothered as I have printed a 1/100th scale that works ok.
But I am thinking of making a tacco for the lap speed. As my machine's speed seems way faster than most. Minimum speed is about 60 to 100 rpm. I am not sure if I am exceeding the maximum RPM on some of my laps.
How did you implement the RPM counter on your conversion?
Have you found it useful?
The alternative is to use a strobe to measure/check lap speed at the dial settings and mark the position of the maximum lap speeds on my dial.
regards
Flash
Flash,
I am using a hall effect sensor and 4 magnets at 90 degree intervals. Pretty easy to do and I think my son might of even written some better rpm code than mine that is being used on the teams motor test rig. I am bit busy with other stuff atm but could help you make something when I have time. You could probably make something up with about $10 of parts.
Do I use the rpm ? No :), I don't really care about laps speed and go with what sounds about right, and crank up the speed when polishing. Still good project and a good introduction to arduino if you decide to make one.
Cheers
MB
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Hi Makky,
I might take you up on that. I haven't played with electronics for over 25 years. And it is over 30 years since I did any hex programming.
My latest project was a twin 10 amp 12v supply for my concave prototype. It is really just a 25a 12v swich mode supply with 2 speed controllers. Way over rated for my motors but enough grunt to drive a couple of 90w motors in need.
I hadn't thought of hall effect sensors. My thought was to drill a hole through the drive pully and use an opto coupler with a counter with a 1hz window before it resets.
Regards
Flash
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Hi Makky,
I might take you up on that. I haven't played with electronics for over 25 years. And it is over 30 years since I did any hex programming.
My latest project was a twin 10 amp 12v supply for my concave prototype. It is really just a 25a 12v swich mode supply with 2 speed controllers. Way over rated for my motors but enough grunt to drive a couple of 90w motors in need.
I hadn't thought of hall effect sensors. My thought was to drill a hole through the drive pully and use an opto coupler with a counter with a 1hz window before it resets.
Regards
Flash
Did you see these pics ? I'm sure you can do a tidier job. Use nice thin magnets.
How big a display do you want? You don't need a sensor board like the one picture, you just need the sensor and a pullup(maybe down have to check) 10k resistor. Might also be worth putting a 0.1uf decoupling capacitor across the +ve -ve of the sensor, probably also between -ve and output. Hall effects sensor work really nicely. Just need a bit of filter code to remove any flicker when switching. Then either count the activations over a time period or measure the time between activations to get rpm.
(http://aussielapidaryforum.com/forum/gallery/7/medium_5704-270815103817.jpeg) (http://aussielapidaryforum.com/forum/index.php?action=gallery;sa=view;id=7568)
(http://aussielapidaryforum.com/forum/gallery/7/medium_5704-270815104644.jpeg) (http://aussielapidaryforum.com/forum/index.php?action=gallery;sa=view;id=7569)
(http://aussielapidaryforum.com/forum/gallery/7/medium_5704-270815104811.jpeg) (http://aussielapidaryforum.com/forum/index.php?action=gallery;sa=view;id=7570)
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Thanks Makky. Wil follow up once I finish the Christmass presents and then my prototype concave facetor. Mrs Flash put her foot down and requires the presents finished first. But getting close to finishing the project.
Had thought of patenting the design, but would have to sell 100 units just to cover the cost of the Australuan patent, let alone foreign patents. It'll be easier to make the design public and try to claim copyright to the designs. Given I don't know how durable the motors are, not having to worry about warranties is a plus. At under $20 they are cheap enough to replace.
Regards
Gordon
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Hey everyone sorry to dig this back up but I'm looking at buying a brand new machine and I either want to start digital or get as much digital as I can I'm going to purchase the book so I know more before I spend any money on a faceting machine. Sorry if I should of started a new thread.