If you mean the stuff ford put on the cars, the only way is to scrape and wire
wheel it off. Make sure you use eye protection and a mask of some sort. You can
try some type of cleaner but it will only melt the undercoating and make a big mess.
It takes a long time. After you get it off you will have to use something to protect the
metal or it will rust. I'v herd you can get 13-15lbs of it off the cars. A heat gun will work
also but it is not a safe way to do it. It is some bad smelling stuff.
I did the complete undercariage of my car last year. Did it with scrapers, wire wheels of many assorted shapes and sizes. Then primered the metal, painted 2 top coats, and then undercoated it. Looks great, but you will find out it's one of the BIGGER pains in the #@%&
I put a box fan behind me to blow the dust and debris away from me.
A lot of the time the under coating is so old that if you get several gasket scrapers or chisels and a hammer, the stuff chips off real well.If you can get your hands on a rotisserie it makes the job easier than doing it on your back.
For removing it from small areas, I used a propane torch and a small paint scraper. For complete details, see my earlier post titled "Poor Man's Napalm". I'd suggest wearing gloves whatever way you go.
I put my 69 mach on a rotisserie, turned the car up-side down and soaked a couple old towels in kerosene. Left the towels lie on the chassis for a couple hours (varies on thickness) and the old undercoating peels right off. A little cleaning with a rag and the old paint/primer remains intact. Move the towel/s to do a section at a time and the results are amazing.
Forget the torches and wire wheels. Go to Eastwood's
website and order their "Undergone" system. I used it on the firewall of my 67. It's a fomay spray that
softens the binder of the undercoating to a thin consistency which you can then scrape off my hand
using a stiff putty knife. Hardly any fumes either. The system comes with cleaner/degreaser to use after
scraping to get the last of the gunk off. Their catalog makes it look like you can wipe the stuff off with
a paper towel - it's not quite that easy. But you can scrape by hand without having to resort to the wire
wheel. I was happy with the results.
'67 C-code 'vert (Dees67)
'69 GT FB (project car)
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