To properely plate the stuff you WILL have to wire wheel all the threads on the bolts cause the chemical bath WILL not do a good job. Yes the chemical baths help. You might have to chase all the internal threads and dress up the sides of the heads. cause if you're going to the trouble you might as well do it correctly. Otherwise ... You will have spent the $$$$ and have areas on those threads not plated. Think about zinc.
I have to do this w/ my whitworth nut, bolts, and machine screws cause they are expensive when I have to buy them from the UK. I have antique bikes and most of the hardware is cadmium plated. I buy new hardware for my USA bikes and cad plate them after buying perfectly good hardware in zinc.
my .02
Ps at my local hardware surplus shop I buy by weight, NOT each. it's a bit cheaper cause this shop deals in steel, hardware, surplus steel, mill shop rems, aluminum, some plastic and stainless. some of that is fasteners and fabrication pieces.
you guys would LOVE this place...
it's not cheap.

Jim & Caroline
The highway is for gamblers, better use your good sense."
Gooday-that's my 1¢ answer due to the lousy economy ~ cause I ain't got - no . mo . doe
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