Removing undercoating 77 Formula
 

Inspired by others, including a couple of threads I saw here, I started removing the undercoating on my 77 Firebird.
So far I have used a heat gun, followed by plastic scrapers. Residue is hit with a rag and mineral spirits. Also tried WD40.
The job doesn't go quickly from the little I have done, so I plan to just pick at it a few hours at a time.
Anyway, thought I'd share since I was motivated some by some pictures posted by others.
Ill try to post pictures of the little progress so far.
If anyone has Qs, or tips, shoot.
Here are a few at the start ...

And here is a little progress....

Out of curiosity, is the purpose to remove weight, or to make it original or to prevent corrosion?

More trouble than its worth.

I'd look for a place that does dry ice blasting.

Make it original.
I've started now, no stopping!
I had dry ice blasting done on my 1967. Did not really do a good job of removing undercoating and wasn't cheap. I did not find that worthwhile in that experience.

Don't use a heat gun in my opinion. It heats it up and creates more mess. If it has hardened it usually scraps off better. Your just gonna have to scrap it off area by area. The best times to do this, is when restoring the car and is completely disassembled and put on a rotisserie. It's alot of work as you know.

I had a bud who had one ta done w/ ice blasting, he said it worked.
My 78 had a few sprays, had to be the dealer, wd40 and a tooth brush worked.

Oh been there…have a headache thinking of it. My 78 was Ziebart coated .I used a needle scaler chipped the thicker stuff off very quickly .. The rest of the process was varsol and a plastic brush. I had all lines rear end tank out. I was 2 weeks on my back start to finish. Keep at it it’s a big task, but hey you’re getting there .

Get it ice blasted and be done with it....

Many years ago I was working and happened to be driving by a friend's house He had his 79 TA on jack stands on his driveway and was stripping the undercoating off. I stopped in to say hello and he crawled out from underneath wearing something that looked like an astronaut suit. He had a case of Hog Wash carburetor cleaner and was stripping away. I remember him saying it wasn't as bad as it looked and said the Hog Wash worked great.

Keep up the good work, I'm sure it'll be worth all the effort.

That was my experience as well. Spent a couple grand on dry ice blasting on a 73 Firebird. Did a poor job removing soft gummy undercoating. Did much better on the hard set undercoating. Does clean up the underside in a general sense. Honestly removed more undercoating by completely saturating bath towels with solvent. I wiped it all over the area and let it work for 15 minutes or so. Then went back over it and most came off. Two hours doing that removed more undercoating than all the ice blasting. I used PSC1000 solvent from Tractor Supply. $54.00 for 5 gallons.

Picked up my Formula with my tractor from front, rear wheel up on ramps. Used a REAL Steam cleaner with a degreaser injection and worked perfect.
Have to get STEAM .. Steam has 540 Cal/gram of energy vs only about 80 calories for hot water at 211 degrees.

Picking away at it.

Looks great. Are you putting anything on it after removal?

I don't know. What sorts of things do people put on after removing undercoating? Clearcoat?

I have removed undercoating more than I'd like to remember. That having been said, a stem cleaner is part of my arsenal. The other thing I use is hand cleaner. The regular old white hand cleaner from the parts store.

I wipe it on, and let it sit. I'll wipe more on, and agitate it with a brush, scuff pad, or whatever is accessible. The hand cleaner softens up the undercoating, and loosens the bond to the substrate underneath it. I then hit it with the steam cleaner. It is MESSY! But, it works. I usually have to do this 2-3 times.

After that, I use a CRC product called SP350. I spray that on, and let it soak in. It's a great preservative, gives a dull sheen, and protects any bare substrates in the chassis.

Before and after.........

I am finding it takes some time, but not too bad. Especially on the flat spots. Warm it up with heat gun, peel with plastic scraper. Then spray on mineral spirits and wipe with rag. The nooks and crannies are a bit more trouble ...

Looks great. As much as a PITA that must be, I can see how it may be a bit addictive once you start seeing the results. Of course, that may be too easy for me to say since I'm not the one doing it! LOL.

Got a little more done. Starting to look better.

Putting a wrap to this one and updating for anyone considering doing this.
I removed the undercoating from all the flat spots and easier to get to areas with the heat gun, plastic scraper and mineral spirits.
Took to dry ice for the harder access areas.