Aussie Lapidary Forum

LAPIDARY => Tips and Gadgets => Topic started by: Zircon on December 30, 2020, 03:13:20 PM

Title: Repair Big R double grinder
Post by: Zircon on December 30, 2020, 03:13:20 PM
Hi,
     Can anyone recommend someone to replace bearings in a double grinder from Big R. Commercial rate paid, preferably Southern Suburbs of Melbourne.
Thank you,
                 David
Title: Re: Repair Big R double grinder
Post by: Rusted on December 30, 2020, 04:20:03 PM
If that isn't attached to a bench take it into any local engineering workshops, if you can find one that isn't on holidays.
You might be able to do it yourself, I think the bearings are attached to the shaft with a couple of grub screws, find the correct allen key undo the grub screws, you will also need to undo the grub screw on the pulley, clean any rust or gunk off the shaft, give a squirt of WD40 between the shaft and bearing and then gently tap the shaft out with a soft hammer. Don't bruise the ends of the threads or you will never get the nuts back on again.
Title: Re: Repair Big R double grinder
Post by: Zircon on December 31, 2020, 12:16:11 PM
Thanks Rusted,
                      There's a metal spacer collar jammed on the shaft. It will need to come off and I was a bit hesitant to attack it with a small grinder. Will have another attempt.
Happy New Year
David
Title: Re: Repair Big R double grinder
Post by: Rusted on January 01, 2021, 08:07:43 AM
Try some heat on the spacer, you need to get a lot of heat quickly onto the spacer so that it expands, once the heat soaks through to the shaft you are back at square one as the shaft will expand too, clean the shaft back to shiny metal first. Also try tapping with a small hammer all the way around the collar to break any rust or crud holding it on.
Title: Re: Repair Big R double grinder
Post by: Zircon on January 11, 2021, 12:09:21 PM
Thanks everyone for the advice. I tried all suggestions but was stymied. Then I went to "Jack McNamara" an AutoTransmission Repairer in Moorabbin. The owner was amazing, a real expert on anything machinery. He found a hidden circlip. All repaired overnight. David