Jewelers spectacle magnifiers

[Bucket]

Haven’t tried to get any further away than about 40mm, the purpose being to get the meet points right.

It sure looks like it works well for you Frank, those meet points look spot on!

[RoughCreations]

I am quite impressed with the quality of the video images - looking to be a workable alternative to squinting into a loupe.
RC

[Faceting Frank]

Cut all the facets to 3k pre-polish on a BATT lap and polished one facet at 60k.
Because the cutting speed on a BATT lap gradually diminishes until you reach the point where it needs recharging. I cut the facets by wiping them across the lap five times as it rotates and then move onto the next facet in that row. Going round and round the stone till they are all finished, if one needs cutting more, they all get cut more. That way they are all cut to the same depth and when the pre-polish stage is finished the meet points are pretty good and just need a bit of tiding up.
In the first picture facets C are still 1200, facets A are finished on 3k and went round the stone four times for that. Facet B is only half finished and still full of 1200 grit pits, but you can’t see them on the screen. So, the only way I can think of cutting the pre-polish is to cut the mains (biggest facets) a bit more than required, then cut the rest to their meet points.
That way you’re only using the 10x loupe on the mains.
The second picture has the centre facet polished, the rest still 3k pre-polish. I polished it only using the screen to spot areas not finished. The lighting position was the key to getting that to work, so it could pick out the 3k scratches.
My conclusion is that it can turn out a stone that would look perfect through a number 5 lens Optivisor, just using the computer screen to work with. But will need a 10x loupe at the polish stage to finish the meet points and polish off if you want that standard of finish.

[mehoose]

LOL, my comments are in your gallery. Again...DANG!

[MakkyBrown]

Those pics look good enough for me Frank, might have to buy one now :)ThanksMB

[Faceting Frank]

Scrapped the mobile phone stand idea, even having a ridged upright section it still wobbled when you touched it. So, went back to the wooden upright and boom idea.
 I have a magnetic protractor to put on the boom, that angle will always be the same relevant to the facet angle and the distance the boom is out will be as well. Only the height the scope is above the stone will need to be manually set to suit.
So will make a chart up of the angles etc. so I can quickly setup from one row of facets to the next.
I only have one fine adjustment next to the scope at the moment, which is in the Y axis. Need to have one in the X axis, the Z axis (up down) is adjusted by the focus.
The picture on the screen is the same stone as before, just recut the facets to make it a bit more complex. Still only using the screen to get the meet points, it is at the 1200 grit stage.

[MakkyBrown]

I've purchased a camera, plan on mounting it on a horizontal carriage with linear bearings above my machine. Camera comes with height adjustment screw thread that I might use. If it's no good for cutting I still be able to take video of stones on the dop. I think it will do 1080p at 60fps. If the lens doesn't suit there are a huge range of lens available to fit it.

https://www.aliexpress.com/item/4001260076533.html?spm=a2g0s.9042311.0.0.67174c4dTbppIB
MB
 

[Faceting Frank]

Looked at those scopes, look better quality but to bulky. Won’t be able to get the scope close enough to the stone without colliding with parts of my machine.

[MakkyBrown]

I figure I should be able to get it up above everything as the working distance is a lot more than the microscope you are using. If the current lens doesn't give me enough working distance there are lots of others available.  I'm thinking I'll have a good part of 10cm between the lens and stone.

MB

[Faceting Frank]

Got it polished with 60k diamond, the stone was a 11mm dia. cubic zirconia.

[FlashGP]

Hi Frank,

It is looking good.  I was going to make a CNC based surface grinder for my laps.  But having seen your Renault’s I now think I’ll be setting up a scope before I do that

[MakkyBrown]

Looks good Frank. Speed wise how is it comparing to using a loupe ?

[Faceting Frank]

At the moment it’s taking nearly twice as long because of the fine adjustments I’ve yet to build into it and the light. The angle of the light hitting the facet as you know is key to picking out any scratches. You would normally rotate the stone around under the light till that happened, you can’t do that because the stone has to stay under the scope and the built-in light shines straight at it. You can un index it and rotate it a small amount and I’m finding at the polishing stage I have to do that on every facet.
My current lamp is not flexible enough, so, I’m buying a desk lamp with a flexible stem the same as the mobile phone stand, I bought. The plan being to set the lamp up to suit that row of facets.

[Faceting Frank]

Finished the last of the stones I’m entering in the AFG comp, which was the crown of the Happy birthday concave. So back to work on my scope stand. Got the fine adjustments for the scope designed so will get started on that tomorrow and fit it to the end of the boom. That’s going to speed things up a lot.
 Also realised I can mark a “home position” on the mast in pencil for each row of facets and when the stone is finished rub them out. That’s going to make it quicker when I change laps, also if I want to change the angle of the scope to look at the girdle meet points for example and then go back to those facets.
Sticking to the wooden mast and boom, though will make a more professional looking setup, rather than something a 12 year knocked up in school  woodwork class. I like the large surface area between the two surfaces that require minimal pressure to keep them in place.
Apart from the speed (which I can do a lot to improve on) I really like it.

[Buch Metter]

LOL, my comments are in your gallery. Again...DANG!

Unbelievable!  I haven't seen you around for years, good to see you are still into it.