Body / Glass: Undercoating

[dokelle]

Anybody got a good solution to removing undercoating?

[sweetolbob]

Heat gun and a putty knife ground to a sharp edge. Easier than taking the paint off an Avanti with a razor blade. But not much more fun, Just heat it enough to soften it not melt it.

Bob

[dokelle]

Well that's what we had been doing, was hoping there was a better way.

[R1 3137]

IF the undercoating is thick enough I have found Cold can be better than heat to get it off.
I sharpened up a cold chisel and started attacking the edges of some 1/8 in or thicker coating and it just sorta chipped off like it was ice. It was a much more aggressive action than the razor blade but it was also much faster IMHO. Came back with the razor and W&G remover to get the last of it.... It was faster than sandblasting it.

[Charlie D]

I used a needle scaler. Pretty slow going though. I had to have ear protection because of the noise.

Charlie D.

[52hawk]

I used an acetylene torch and a scraper-hotter and quicker than the heat gun.

[swvalcon]

I've found the best thing is one of those small propane torches and a putty knive. You can controll the heat better this way. Torch in one hand putty knive in the other.

[RDWEAVER]

I used a putty knife and a small mapp gas torch. Two of us worked 3 or 4 hrs a day for a week if I recall correctly. It will not come off very well with a blaster it is too soft. Once you scrape it the remainder will come off with soda blaster or bug and tar remover.

[wdills]

I used a Rockwell Sonic Crafter, one of those new oscillating tools. Used the side edge of a scraper blade. Went after the undercoating cold. In most areas it flaked off nicely. It was still a little soft in others and didn't flake off. In the soft areas, it would still scrape off but was just slower.

[dean pearson]

In the end to get it all off you will most likely be using all those methods. (scaler at cold temps first for the thick stuff or large areas) Bottom line is it aint easy and it aint fun, The only good thing is when you do get it off there is usually good sheet metal under it.
My 52 was coated to heck and back again, inside and out on the floor and trunk. Now that all my body work is done I'm trying to figure out the best way to coat it all over again.
It took me over six week ends and what ever week days I could fit in.

Hope that makes you feel better

Dean.

[s2dwagon]

I used heat, as described above, except I did it on a little larger scale. I used a propane torch too, except I used the brush burner wand type that was on a bout a 6'-8' hose, attached to a 5 gallon propane bottle. The car was on a rotisserie and void of any other parts (gas tanks, wiring, brake lines, etc.) so I wasn't too concerned about catching something on fire.

I would heat up about a 3' x 3' section, always keeping the wand moving back and forth, side-to-side. You'll know if it gets too hot. Where there's smoke, there may be fire. Anyway, doing it this way, the heat is held in the floorboard and keeps the undercoating soft and pliable for quite a while so you can work that area until clean. I also used a putty knife to remove the coating. If you use this method, make sure you have some kind of covering on your garage/shop floor just to help avoid further clean-up.

After I removed all of the undercoating, I then hauled it off to the sandblaster and had the whole body media blasted. Then, after I got it back, I applied a tintable truck bed liner to the bottom/wheel wells for undercoating.

--Scott

[rusty65]

This may not work for everybody, but it worked to get the undercoating off of the front (belly pan) of my Daytona.After using scrapers, flat screwdrivers, and wire brushes and wheels,carb cleaner was my friend.As you know it stinks like heck, and dispose of your used rags properly.Being a CASO I didn't have an air chisel or a torch handy, so I just went with the carb cleaner.What a time saver!

[jerezstude]

In my area there are several industrial powder coaters that have large baking ovens. Loosens undercoating to the point it falls off. I find it to be very cost efficient and a time saver. I also powder coat my frames and chassis parts. They bake, blast and paint, I pick then up a later week at a cost far less then I could begin to match doing it myself and it's almost indestructible. Jerry Kurtz

[SScopelli]

A Hand torch and putty knife works great..

BUT Make sure you heat the putty knife and not the undercoating!

The logic behind my statement:
A hot knife cuts butter better than heating the butter..

[rockne10]

This subject has been inquired upon a couple dozen times over the years and you can review all the responses and duplication of responses by using the "SEARCH" box in the upper right.
Chipping big chunks cold where it has not strongly bonded is by far the most satisfying.
The hot knife through butter seems the quickest for those thick areas that are in fact adhered.
Thin layers with good adherence and final surface cleaning is most complete by using solvents. In my case, I used diesel fuel.