The Stovebolt Site Forums The Shop Area General Truck Talk How to un-chrome plate something?

I've got a nice valve cover with the exception of someone chrome plated it.
What's a good and or easy way to remove it prior to painting?

Looks like it may only be chrome, no copper, and I'm not sure about nickel.

Grigg

I've used 80 grit to unchrome a bumper.

Give it to a kid and tell him not to take the chrome off...

I'm not excited about using abrasives because of the detail in the letters, overall it's already clean and straight and I don't want to remove any more material than necessary.

What does a chrome shop do before replating something that was poorly done to start with?

Grigg

I managed to prep a valve cover for paint/POR-15 in a floor standing sand blast cabinet. It made all kinds of funny sparks when the abrasive hit the chrome but the fairly fine abrasive left just enough key to make a good bond, no distortion that I could see took place. It was more a surface roughening than a material removal. Perhaps try your abrasive of choice on a scrap of something of similar weight before your valve cover?

I believe they do it chemically but I might be wrong. If it's sticking just abrade it and paint over it.

all you have to do is cut the gloss enoughto provide tooth for a good primer

chrome shops hand grind old chrome off, that's why it's more expensive to RE-chrome something

Bill

Reverse electrolysis is one process that some plating companies use, another is the use of Muratic acid solution. If I remember correctly, brake fluid was never a friend of chrome either!

Contact your local plating or powder coating company and ask to hear their method of de-chroming.

Another thought is to trade with someone that would love to have a chromed valve cover.

I was watching Powerblock this weekend and they had a segment showing Advance Plating in Tennessee that was flooded last year. They put their parts is a caustic bath to strip them. I don't know if that's SOP or was just used on their parts.

Use a good self etching primer, something that'll bite into the surface after you scuff it like squeeze said.
On aside note, it most likely does have a nickel base, that's wha actually gives "chrome" it's color. The chrome part is actually a very thin layer that's used to prevent corrosion in the underlying layers.

...most shops "serious" about de-chroming will use chemicals. its a different world but for 13 years we plated nickel, copper and hard industrial chrome on top of the copper. To dechrome a print cylinder we ran hot water over the cylinder and then poured muriatic acid on it.....chrome gone! Its some nasty stuff though and anyone trying it should wear a respirator and be very careful.... .watch where you throw those dirty rags.

I was going to mention muriatic acid also. I don't know about chrome, but I poured some through a regular metal funnel and it took the shine right off of it.

Have a chrome place de-chrome it, or get a different one.

I'll see what I can do. It's derusting now, I'll deal with the chrome next.
It was left outside upside down with pieces parts in it for quite some time before I got it, inside was rusted pretty bad but looks to be cleaning up quite nicely.

It's a reasonably rare valve cover for my Detroit 4-53. Early on they made them just a few years that said "General Motors Diesel" then after the company name change all the later ones say "Detroit Diesel".
I'm not likely to find another one any time soon, at least I haven't yet in the several years now I've had my eye out for Detroit parts.

Grigg

I think that if you take it to a chrome shop, they will remove all of the rust and the chrome at the same time.
Chris

Rust is about gone, or so I hear. Ill get it back sometime soon and post some pictures.
Not knowing what to do with the chrome from the start I figured the rust was manageable so tackle that first. Good to know for next time that it may be a two for one deal!

Grigg

Here's the new and the old, or is it the old and the new...
http://rides.webshots.com/photo/2181396090080251109PMwezY

This one shows the not so great looking chrome.
http://rides.webshots.com/photo/2773112840080251109ELVkyz

Rust is pretty much gone, a little evaporust will finish it off if necessary.

Chrome is next.
I'd really like to remove it because I'm afraid if I just scuff and paint then later the chrome will continue to peal.

Grigg