On Mar 24, 11:57*am, durabol wrote:
I'm new to electroplating and was wondering if anyone could provide
some insight (and save me from reinventing the wheel) in the following
methods of electroplating an aluminium cylinder bore both for
protective reasons and also restoring a worn cylinder bore back to
spec. so don't need oversize pistons. This is for a homemade two-
stroke engine, seehttp://groups.yahoo.com/group/DIY_2S/for more
information.

Cylinder Bore Protective Plating:
-Hard Anodizing, high silicon aluminium, easiest
-Electroless Nickel-Phosphorous/NiP: can do it in one step, hardness
close to chrome
-Nickel Cobalt: not sure if can get enough cobalt in nickel to be
useful?
-Nickel/Suspended Particles: trapping hard particles suspended in
solution into nickel plating
-Nitride: similar to how some metal tools are protected, not sure if
possible/practical
-Hard Chrome: tested and proven but an involved process

Plating Cylinder Bore Back to Spec., need thick deposit, these are
some metal I thought would be possible:
-copper
-nickel
-iron
-zinc
-tin: have heard of pistons being plated with tin for less friction

Brock

If you're doing a one-off, it'd be better to let somebody do the
plating for you. Plating aluminum and getting a good bond is tricky.
Not saying it couldn't be done at home, just that you'd probably end
up with an engine full of nickle flakes a few times before you got the
hang of the process. On any of the plating processes, the first item,
after polishing, is removal of the oxide film and keeping it removed
until the plating occurs. Poor prep=peeling plate.

Anodizing would be about the last thing I'd use for a surface I needed
low-friction sliding on. It's basically a glass-hard, very fine
abrasive surface.

Now if you're really going to get rolling in production, a removable
liner of some other metal would probably be the way to go. Wear out
the liner, put in a new one.

Stan