Topic: Suggestions to remove heater box stains

[CT428CJ]

I am restoring a 1968 heater box. The case half that will be visible from the passenger compartment has the original date code on it but is also stained.

The stains can bee seen in the picture just to the left of the manual door.

Does anyone have any suggestions on how to either remove the stains or finish the rest of the case so that they will not be so visible?

[Bossbill]

Are you referring to the area on the left of the second pic that appears shinier or duller than the rest?
I did some repairs on mine and then shot the case with a very low gloss clear.
You can either experiment with other damaged cases or the rear of yours.

[Coralsnake]

I have tried a number of techniques, but I think Bill is right on. A very light glass bead to get a uniform finish followed by a clear coat will bring the correct finish back.

[jwc66k]

Lots of masking, lots.
Jim

[Bossbill]

Be sure when you glass bead stuff like this you don't use HF glass "bead", since I'm fairly certain that's just chopped up glass. That stuff has really good action (80 grit?), which you don't want.
I use Ballotini medium to fine glass beads which are actually beads or round balls. When used with delicate stuff I'm in the 20-25 psi area. I hear other have success with walnut shells.

[CT428CJ]

Are you referring to the area on the left of the second pic that appears shinier or duller than the rest?

Correct.

Be sure when you glass bead stuff like this you don't use HF glass "bead", since I'm fairly certain that's just chopped up glass. That stuff has really good action (80 grit?), which you don't want.

Right, got it, thanks.

Any suggestions for the clear?

Not sure what the stains are from. It's too bad since the rest of the box is really nice. Mint sheet metal and the original core.

Any other ideas before I resort to bead blasting?

[Bossbill]

Clean it and try Rustoleum clear matte or flat before doing anything else to see if you can get the gloss level to be uniform.
Rustoleum makes 3 clears: Dead Flat, Matte and Satin. All of them have uses on a restoration.
If you have spray equipment then a 2k clear with flattening agents.

Here is mine with a matte clear:

[CharlesTurner]

I recently tried soaking heater case halves in evapo-rust, had great results.

Example below.  Has not been clear-coated, only some mother's mag polish used after soaking.  For an Oct. '64 San Jose car... so be careful if using as a reference for other plants as some details may be different.

[CT428CJ]

Interesting, thanks!

I have some stuff soaking in EvapoRust right now. I'll try a spot treatment to see what happens.

[CT428CJ]

I decided to try a few other types of cleaners before resorting to bead blasting.

Several rounds of Permatex plastic cleaner followed by rinse with lacquer thinner and sponge off did the trick.

[Countrysquire]

That came out very nice.  Even though I have a vapor blasting business, I always recommend that you try other, more gentle methods with parts like this before subjecting them to blasting.

[CT428CJ]

I found something that  works even better: https://goofoffproducts.com/product/pro-strength-remover-6-oz

I had another spot on the side of the box and had just bought a can of the pro-strength goof-off to remove some latex paint from wood trim.

I decided to give it a try and discovered that it took the stain out completely after 3 easy applications.

[jwc66k]

A word of warning about "Goof-Off". It is a paint remover. If left too long on a painted sueface, like a minute, it will remove the paint. Don't spill any, splash any or leave a Goof-Off soaked damp cloth on a painted surface. Careful usage in the kitchen can remove really stuck on food stains and dirty finger prints. Goof-Off may contain acetone, which also works well. Another good product is Krud-Kutter available at Home depot. The odor of Simple Green Makes me sick, so I don't use it, others do.
Jim

[CT428CJ]

And be careful with soaking the fiberglass case in EvapoRust.

It will result in discoloration (lighter shade) of the case.