Techniques to remove the underbody protection?

[Chrome58]

Hello everyone,

Does someone has a good technique to remove the underbody protection (the tar-like material) ?

I've looked at several videos on youtube, and then tested "Goo Gone", "Goo Gone Pro Power", heat, mechanical scraping, wire wheel, and any combinations of all of those ... but it's a real pain in the back, and none of those solutions are really efficient.

What are your experiences ?

 

[Shakerdave]

Aircraft remover. You'll need to be careful as it takes it to bare metal. Also wear protective gear when using.

 

[halifaxhops]

Absolute best I have used is easy off oven cleaner then pressure wash it off, amazing!

 

[CBODY67]

Many drag racers used to scrape that undercoat off in the prior decades, in the search of that "low e.t." due to less weight. "Mechanical" was the way they did it, back then, but ought to be something more advanced in these times. Remember, you're dealing with an oil-based product, so that might give you some guidance.

Just some thoughts,
CBODY67

 

[MetalManiacAZ]

Stay away from any high speed grinding/wire wheel removal methods. As Shakerdave and Halifaxhops said previously, chemical stripping is your best bet.

There's a good possibility the undercoating contains a few percent asbestos. You don't want to be under the car grinding away and breathing that ****.

 

[bnz84]

Absolute best I have used is easy off oven cleaner then pressure wash it off, amazing!

Ive used that combo too. Easy Off (dollar store brand) loosens everything up and the pinpoint pattern really makes short work of things. What I like is no dust & dirt. But doing this under a car could be difficult. Nothing like spraying into a pocket and having 3000psi shooting back at you. Of course once I get it set up and I get wet I usually end up cleaning the sidewalk, and tractor, and shooting down bee's nests, and....

 

[cbarge]

Propane torch, putty knife/scraper, wire brush and elbow grease.
I hit the crap with the torch to soften it up then comes off like butter when scraping. Finall clean with wire brush.
Yes I did wear masks saftey goggles and old clothes I threw away.

 

[Lee Robinson]

Propane torch, putty knife/scraper, wire brush and elbow grease.
I hit the crap with the torch to soften it up then comes off like butter when scraping. Finall clean with wire brush.
Yes I did wear masks saftey goggles and old clothes I threw away.
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In my experience with Ca. cars and standard undercoating, I use a scraper and a hammer to chip it out. It will usually come out in chunks.
Then a tar remover or wax and grease remover for the residue. I realize heavy rust in salt country is a whole different animal. From Chrome58's
post my assumption was he was talking about removing under coat. For heavy rust, media blasting would be the best route, but to do it right
one would need a rotisserie.

 

[MrMoparCHP]

Personaly I had great luck with a heat gun and putty knife, I heated just ahead of the putty knife keeping the putty knife hot. It just slid off, I have only done small areas, this panel only took 30 minutes (if that).

Alan

 

[Ross Wooldridge]

Heat gun, putty knife, wire wheel (with masks).

Canadian built cars got an incredible amount of undercoating... many pounds of it. I filled a 40 gallon drum about 2/3 with the scraped off stuff.

 

[Chrome58]

Thanks a lot for all your feedback on different techniques.
As I see it, the secret ingredient is ... elbow grease and patience.

Canadian built cars got an incredible amount of undercoating... many pounds of it. I filled a 40 gallon drum about 2/3 with the scraped off stuff.

My car is canadian built.
That would explain indeed the big amount of undercoating I'm facing.

 

[MrMoparCHP]

I used a method that I felt would create the least mess, nothing being flung about. Didn't require any expendables, propane, wire wheels, sanding discs, etc. I did need to buy a heat gun but it is a tool I use for many other things.


Alan

 

[68PK21 440.6bbl]

Don't steam clean it, I tried, up the heat and the soap, it'll make a big mess on the ground and yourself if your not careful.

 

[Bryon Mason]

Currently undertaking this as well, some great pointers on here im going to try. I'm currently using a needle air gun and its working pretty efficiently on the bigger areas.

 

[BigblueC]

I've used the torch and scrape method before. It works, but takes time and effort. Also be mindful of flammable surroundings. I might have set something on fire a time or two.

It seems like I've seen or heard about freezing the stuff with dry ice, then busting it off by whacking the panel with a hammer.

I filled a 40 gallon drum about 2/3 with the scraped off stuff.

Did you happen to weigh it?

 

[Ross Wooldridge]

Lol, I did not, but I hefted that can around when it was garbage day... not particularly light!

 

[Chrome58]

It seems like I've seen or heard about freezing the stuff with dry ice, then busting it off by whacking the panel with a hammer

Yes I've read about it too, and I even saw a video of a guy using dry ice. It seems indeed very efficient, but as I do not have a rotisserie, I'm working from under the car, which can be complicated for some techniques, including dry ice.

However, I tried "freeze spray" (some sort of compressed air spray) which does freeze the undercoating (frost was forming on it), but it was not enough to facilitate the removal. So I'm dubious about that dry ice technique, unless the much lower freezing point proves to be the key. Which might be the point.

Heat and scrape seems to be the most common solution, but I find it long and messy. Especially when you're under the car ...

 

[bnz84]

Ive been wanting to try one of these recip saw scrapers. Might be a good option.

 

[MrMoparCHP]

Ive been wanting to try one of these recip saw scrapers. Might be a good option.

I got one of those multi tools with this in mind, 2" in I gave up. Heat Gun and Putty Knife is your best bet!


Alan

 

[bnz84]

I got one of those multi tools with this in mind, 2" in I gave up. Heat Gun and Putty Knife is you best bet!


Alan

I was thinking this recip saw blade would be much more robust than a a vibrating multi-tool. Maybe not.