Efficent and safe removal of undercoating... what worked ?

[hoffbug]

I am at that point that I need to figure out how to get the underside of the car cleaned to bare metal. Ive heard that blasting wont penetrate the factory undercoating very well and need to know how you guys have done yours and what works and what doesn't.

[Kenova]

When I did my Nova I used a hand grinder with a wire cup wheel. It worked well but what a bloody mess.
There were a few spots I couldn't get at with the wire wheel so I used a propane torch (really not a good idea) and a scraper. The undercoating came off easier with less mess but did leave a bit behind where the scraper couldn't follow the curved surfaces. After getting most of it off I wiped it down with mineral spirits and then wax and grease remover.
If I were doing it again I would use an electric heat gun and some stiff plastic scrapers.

Ken

[cammerjeff]

If you can afford it I would recommend Dry Ice Blasting, It is excellent for undercoating removal. In the class I took 10 years ago, the Demo team came to the shop and removed the Factory Under Coating from the 72 Trans Am we were working on, and the process left the paint intact! Very little debris other than the under coating. The process flash freezes the under coating, making it brittle and then the pressure removed it in chunks. They did the entire car in less than an hour.
I don't remember what it would cost to have it done though. Here is the link to the company site

http://www.blastcleaningdirectory.com/Countries/USA.htm

[hoffbug]

That is interesting Jeff. There is a place south of me that rents equipment.. Im going to give them a call and see what it would cost.. I also have ordered an air powered needle scraper.. Might also work well to lay the dry ice on the undercoating and hit it with the scraper...

[hoffbug]

Checked on the local place that does Dry Ice blasting... They are a mobile company and the estimate on rental of equipment was $500 for the unit for the day, about $400 in dry ice and you need about a 50 horse screw compressor .. He said he thought to have them do it might actually be a push as far as price.. But that the screw compressor puts out about 100DB .. Probably not the greatest thing to have running in a residential neighborhood.

[my79monza]

My Monza had been Ziebharted and I had given up on removing it as nothing I tried really touched it.
I came upon an Idea one day and tried it, I got a paint brush and dipped it Dexron III ATF and soaked it down.
I would brush it on 2-3 times a week for a month-5 weeks and at that point I could scrape it off fairly easy.
I got out my pressure washer and with the 0 degree nozzle removed about 95% or better of the coating.
The rest I was able to remove with a rag soaked it mineral spirits.
did it on my patio and I had that crap everywhere, house siding, garage door and on the cement so then I had to wash down the house and garage door.

This is what worked for me, sure wish I had tried it a year ago before installing the engine.
Merle