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removing undercoating

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BRSLimited

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Anyone have any suggestions for removing the tar like undercoating? Only thing I've found so far is torch and scraper. Hopeing someone else might have some ideas that are less toxic than inhaling that stuff. I'm trying to get as much off as possible before it goes to the blaster next week.
 
Lots of time and efort. Be carefull using a metal scraper you can dig into the metal. Try using a plastic bondo spreader to remove the heated undercoating. Also dont't heat the metal to much with the torch. You don't want to distort the metal, or start a fire. This is a very dirty job that can take a lot of time. For a final cleaning you can use mineral spirits to clean off the light stuff. It's a good idea to have have a fan blowing in the direction of your work.

The blaster will not be able to remove the left over undercoating. You can have the car dipped, but that can lead to other problems.
 
BRS,

I have been using a heat gun vs a torch to scrape mine off.

Another messy option, but it works quickly, it a knotted wire brush on your grinder. I have a 4 1/2 dewalt fitted with this brush and it does a good job of stipping. It does make a real mess though as you will have bits of undercoating everywhere.

Cheers,
M.Pied Lourd
 
I'm mainly concerned with getting it off the underside of the fenders, inner fenders, and bottom of the trunk floor. Floors and sills are being replaced. I know stripper won't touch it, even aircraft stripper. From what I'm finding this stuff did more harm than good.
 
I used a torch and a stiff, springy scraper for my rear wheel wells and other places I found it. once I had the heavy stuff off, I used a wire wheel or cup on a grinder.

hym
 
I used stiff and flexible bladed putty knives with the square corners rounded off on the stiff one.
Another little tool that I used was an old ice pick that had been ground down to be more like a knife. I got it in an old auction box, not prison, and found it very useful with several tasks during a restoration.
 
Heat. I used my halogen work lights to heat the back side of the panel I was stripping. Be patient, it will tend to get soft next to the painted surface, and scraped it off using various scrappers, wire wheels, etc. My wife had a box full of little brown scrapers that came with stone ware. They worked best for me at times. Some spots are hard to heat from the back side. I used a heat gun there. Good Luck.
Tim
 
Engine degreaser works well, kind of messy though. Put down tarps to catch the run off.
 
I watched a fellow use a pneumatic needle scaler for this job. Noisey but very effective.
 
I agree with the advice of heating the metal, that's how I got most of mine off. Works best if the coating is thick, you can get the layer next to the metal to release while the rest is still solid, and remove it in large sections.

I don't know if they sell it anymore, but there was one of the "Gunk" engine cleaners that came in a can (not a spray on foam type). I think it was basically kerosene and detergent. I used that to soften any remains, let it sit for a while, and it does a pretty good job of dissolving what's left, at least with the undercoating that was on my car (a tar-like coating)
 
BRSLimited said:
Anyone have any suggestions for removing the tar like undercoating? Only thing I've found so far is torch and scraper. Hopeing someone else might have some ideas that are less toxic than inhaling that stuff. I'm trying to get as much off as possible before it goes to the blaster next week.
Click to expand...

When we restored the TR250,in 1983, we found that the PO had sprayed the entire body shell with undercoating - inside and out. I used gasoline and a scrapper, and maybe a years worth of old newspapers. Definitely an outdoor project - and I don't smoke! It did work. The tar gets very soft, but I would never do it again. :nonod:
 
I finally gave-up trying to strip it by hand and sent the whole body shell out for chemical stripping. It was FAST, and it came back CLEAN. Yes, it was expensive but in the end for me it was the best way to go.
And YES, you do have to seal / coat the areas that are hard to get to once it is dipped; but it can be done.
 

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I unfortunately have nowhere nearby to take for a full chemical strip or I would go that route. Guess I'll just keep with the heat and scraper and then cup brush on a grinder (yes I will wear eye and ear protection). Most of the stuff on the inner fenders is coming off in sheets where it has come loose from the nice shiny original paint under it. The stuff thats stuck seems to come off ok with heat.
 
This is how I removed mine. BCF
 
I just had a car blsated, two weeks or so ago, and all the undercoating was GONE when it came back.
 
propane torch and scraper seems to be doing a pretty good job. Get some of the hard stuff loose and next thing I know I've got a big sheet of it coming off. The blaster told me that if I get the majority of it off the blaster will take the little stuff off, guess we'll find out. Found an interesting tag in the LH rear wheel well while scraping the undercoating off. The numbers on it don't seem to jive with any other numbers on the car. Would this have been the body number at the plant the body was made at? Tag reads ZS 030823.
 

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Funny what you sometimes find on these cars. My wifes MGB when I restored it, still had the original paint under the tail lights. There was a pair of initials put there with a yellowish paint. I was told that sometimes the painters would put their initials there just for the fun of it. How true this is, is anybodys guess. They were taken off when the body was stripped, sorry to say. PJ
 
BRSLimited said:
propane torch and scraper seems to be doing a pretty good job. Get some of the hard stuff loose and next thing I know I've got a big sheet of it coming off. The blaster told me that if I get the majority of it off the blaster will take the little stuff off, guess we'll find out. Found an interesting tag in the LH rear wheel well while scraping the undercoating off. The numbers on it don't seem to jive with any other numbers on the car. Would this have been the body number at the plant the body was made at? Tag reads ZS 030823.
Click to expand...

My TR4A body had the same thing in the same wheel well. It was a replacement inner body shell which did not come with any tags so I had nothing to compare that number to. Unfortunately, I don't recall looking for the number on the original body shell to see if it matched the body number on the tag.

Scott
 
Unfortunately with all this cold and snow I havent been able to roll my body tub outside, but iv'e been going the wire wheel + 20 layers of protection route to strip the undercoating from my TR6 tub, and following it up with a lower pressure sand blasting to clean the last bits off., it's slow, but it's working well. I'm waaay behind where I wante dto be at this point though, mostly because of the weather not cooperating. =(
 
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