Pits in steel

[sthomag]

I'm refinishing a chrome-plated motorcycle headlight. It had a lot of rust on it. I have removed the chrome plate with reverse-plating, and sanded off most of the nickel and the rust. However, some of the pits are pretty deep, and I can't get them down to the shiny metal. They have a dark gray color. Can I remove this oxide with Naval Jelly before strike-plating? Or does that leave a deposit too?

Thanks

[fly]

Re: Pits in steel

JUst purchase some muratic acid and dip it in that for a few minutes. It will eat the rust away.

[MrRage]

Re: Pits in steel

and metal too - so don't keep it on for too long.

[sthomag]

Re: Pits in steel

I used muriatic acid to reverse-plate the chrome off. The trouble is, it flash-rusts when you take it out. Muriatic acid is not a good pickle for steel.

[fly]

Re: Pits in steel

I found that if you rinse after the acid then go in the degreaser it will help with the flash rust, and don't let the part dry, go straight to the copper or nickel before it has time to rust..

[eprigge]

Re: Pits in steel

Don't use the naval jelly, it will leave a deposit of iron phosphate on the surface which is difficult to remove and can't be plated over. I've found that muriatic acid works great but the surface is so clean and 'active' that it rust very quickly, you've got to rinse and plate ASAP. You can fill pits with standard 60/40 solder and then sand the whole thing flat prior to plating.

[artracing]

Re: Pits in steel

Good question on pitting but I think the question of pitting has not been answered.
Do you fill the pitting with something to make it uniform?
Rob

[fly]

Re: Pits in steel

You have to plate the part with copper then solder in the pits..or if you have enough metal just grind the part down.

[moto-chrome]

Re: Pits in steel

When I do motorcycle headlights, mirrors, kick stands etc. I use Plum-Loy paste and heat it up from the back side. The stuff is wonderful because it fills in pitted or orange peel surfaces and it sticks directly to iron and steel. I sand it down then flash copper it.