Yamaha YA-1 Resurrection

[Yamanatic]

Gasket time! I am sure many here probably already do it this way, but just in case it has never come up...
Smaller gaskets are easy; make a tracing and get out the Exacto knife and hole punch, and go to it. But if a big gasket (like a clutch cover) is needed, it can be a real pain to get right. OTC gasket material comes in a roll, which makes no sense because gaskets are flat. Here's a method that usually works first try:

To start, the gasket material is flattened (sort of) using a hot-water soak then laid out on a piece of board with the side-cover on top. Next, several drywall-type screws are ran into the board through the cover's bolt-holes, and tightened down to hold the gasket material firmly sandwiched between the cover and board. Then using a box cutter (my preference), cut around the OD giving the exact shape that looks pro on the edge that will show after installation. 
      
For screw holes (which can be quite deep), a long 6mm drill bit is used, with the angle on the cutting ramps reduced to about 10-degrees to stop he bit from grabbing and tearing the gasket; this minimal angle on the bit is also used for drilling screw holes in plexiglass windscreens without causing stress-cracks or spidering. There was only one hole in the YA-1 gasket, but that's rare. The cover is now un-screwed from the board (by now the gasket has mostly flattened) and the ID is cut. 

A pencil-compass (like those is used to draw drafting circles) is set to the width of the gasket face, and ran around the entire OD to mark the inner margin and give a point of reference. For screw bosses the 'dirty-finger' method works well; with the cover pointing up and the gasket blank held in position with the case screws, press very firmly around the inside curves of the boss edges and your fingers will leave a 'dirt' mark to trace around with the knife. To cut the ID, the box-knife was used except for the Exacto knife for tight curves - curved drafting protractors make excellent cutting guides. And that's it!

Next, the cover gets a trip to the wet-slurry blaster to erase the battery-acid etched cover (wet leaves a very original finish), and the kicker and shifter get re-plated. The pure (99.44%) zinc anodes arrive in a few days for the home electroplating process on the levers. Nickel is too 'gold,' and does not look like the bright cadmium used in the day - zinc is almost cad-white when polished.



Warren

[Yamanatic]

The zinc electroplating worked fine using the new (home-brew) salts mix and pure zinc anodes on the kick-start and shift levers; I had a Caswell Copy-Cad kit before but used their 'secret' Caswell zinc alloy anode (used it up) instead of pure Zn.

The chemistry was nothing exotic being a mix of vinegar, Epsom salt, corn-syrup as a brightener to get that cadmium/white look, powdered zinc-sulphate, and distilled water.
I have a low-voltage plating transformer, but it only goes down to 2V - the surface area of the levers calculated to 1.5V so I used the primary windings from a Yamaha coil as a 0.5V resistor; otherwise the zinc plating goes on too fast and leaves a 'sandy' surface that does not polish out well.
Turning the work every 10 minutes, it took a total of 30 minutes per lever. Polishing was done with 000 steel-wool. Engine electrics are next.


 
Warren

[Simmons1]

That's pretty awesome

[Yamanatic]

Thanks for that!
Had to refresh 3 times to get the above 3 pics to show. Hope I have it now...
Warren

[SoCal250]

Very nice Warren. You're a mechanic and a chemist!