Lappy Gilmore

Lappy Gilmore - The cheap but plucky lapping machine for watch case restoration

A poor mans lapping machine costing no more than $300 with most parts easily available on Aliexpress.

Video:

https://youtu.be/FzMxyRIWgQ0?si=Ymn4glwSm7A9gLfA

Features:

Powerful (more than you ever need) 0.5HP 3-phase 6-pole 380V 50hz induction motor which can run at 30-1000rpm. Powered by regular home 220V.

Programmable VFD (Variable Frequency Drive) to do the 220V 1-phase to 380V 3-phase conversion. Wiring is straight forward.

Tiltable table for angled work. Can be quickly removed.

200mm disc so that easily available A4/letter sandpaper and lapping films fit.

Most parts easily sourced on Aliexpress or 3D printed. Motor can be sourced locally.

Cheap, around 300 bucks. F*ck paying $13K for a swiss one. Sure it's better, but not 43x better.

Polishing vice and slide, using a 50mm aliexpress lathe chuck. (work in progress).

Motor can be easily slid back for a quick disc change. Discs are cheap at $28 each.

Additional control panel ($10) for easy access to speed and stop/start.

Background:

I have been a watch repairer and restorer for a year or so, and I am always frustrated at the ridiculous prices of tools in watch world. So I have been trying to make my own tools, and this lapping machine is the latest of them. It's a work in progress so dont expect miracles, but I have done some initial tests on an old Seiko case, vertical lapping at 1500 grit, and the results are lovely. Plenty of control at 200rpm. The tolerances of the printed parts are very good (if your printer is setup correctly), so there is very little slop in the whole machine. I still need to work on the polishing vice, and also not 100% sure if I will keep the 50mm chuck, as it's quite heavy. But thats the best I could find for now. I am trying to keep this design as open as possible, as I know how difficult it is to source weird parts. Unfortunately for you yanks, this build is all metric/EU electricity standards. But with some patience you can adapt the design.

Building:

If there is interest I will publish all my 3D print files and give some brief instructions on how to build it. DISCLAIMER - I am not responsible for anyone electrocuting themselves if you decide to go ahead and build this.

Costs:

Motor 0.5HP 3-phase 380V 6-pole induction motor with 19mm keyed shaft (used) - $90 

VFD 2.2kW (220V single phase to 380V 3-phase) (Aliexpress) - $65 

Aluminium Disc 200mm (Aliexpress) - $28 

50mm lathe chuck and spindle/bearings - $65 

Remote Control Panel (optional) - $10 

Another $42 for 25mm alu tube, 8mm stainless rod, printing filament, board, wiring, screws, bolts etc.

TOTAL - $300