undercoat removal

[Bob M.]

Can you use a needle air scaler to remove undercoating without damaging the fiberglass?

Thx

[Mike G.]

Re: undercoat removal

i am using lacquer thinner and a puddy knife on my 72. its takes forever to get this stuff off. makes me want to put my boot to the a$$ of whoever sprayed all that stuff on the bottom of my car. its a quarter inch thick in some places.
good luck to you.

[Paul J.]

Re: undercoat removal

Can you use a needle air scaler to remove undercoating without damaging the fiberglass?

Thx

I assume that the chipping action would make little chips in the 'glass, even if the pressure is turned down. I would not do that. A heat gun, putty knife, lacquer thinner, varsol, kerosene, or other solvent will be the best way. With the putty knife, you can control how deep and how hard you gouge.

However, you might want to try it and see. Be sure to clean all of the undercoating off of the glass so you can see how much damage you're doing, and if you want to proceed or not.

[Rick A.]

Re: undercoat removal

back in the day it was customary to put undercoat on everything - think it was Andy Granatelli or someone along those lines who was the pitchman recommending everyone get their vehicles undercoated

[Mike G.]

Re: undercoat removal

back in the day it was customary to put undercoat on everything - think it was Andy Granatelli or someone along those lines who was the pitchman recommending everyone get their vehicles undercoated

would hate to see those corvette floors rust out.
i remember when undercoating was recommended back in the day. dealers did it to all the cars and added a grand or so for the protection package. i would be happy about that if it had a metal floor. in this case its just a burden.

[Tom R.]

Re: undercoat removal

I spent the better part of a week on my creeper scraping with various sized putty knives and crevice tools aided with lacquer and paint thinner to dissolve the remaining residue. Was mad while doing it but very happy with the results. Just don't scrape too hard and dig into the finish of the fiberglass and keep the area well ventilated.

[Don W.]

Re: undercoat removal

same for me with my '69; putty knife. Hard areas are around brake lines, etc. I even found an area where they molded the undercoat into a square corner where the underlying fiberglass box corner was smashed...Don

[Stan G.]

Re: undercoat removal

Just got done reading my Hemmings daily news letter about using Harbor freights multi-function tool with the scraping attachment for doing the very same thing although it was being used on a metal truck . Don't know if it would be too agressive on fiberglass tho . I have a Dremel tool just like it for woodworking that has varaible speed that you could cut the speed way down . It works by vibrating . The harbor freight tool is only $29 .

[Doug L.]

Re: undercoat removal

I had the body off my '64 and on a dolly built from info on the TDB when I decided that I should remove the undercoat along with the rest of the paint, dirt, grease, etc. I tried doing it for 2 days from underneath on a creeper. That got old real fast. So I fabricated some brackets that allowed me to roll the dolly and body onto their side. With the floor at 90 degrees to the ground the rest of the project took only a few hours.

I had just finished using Capt. Lee's Spra-Strip to remove the paint from the body. It worked well so I decided to try it on the undercoat. It disolved the undercoat nicely allowing me to scrape it off with a plastic putty knife. After most was off I used a rag soaked in lacquer thinner (keep flames well away and work outside) to wipe the glass clean. I did leave the original overspray in the gas tank area and between the wheel wells.

I would not use anything mechanical or metal on the glass. You will gouge it for sure. Once everything is off you'll be amazed at how pristine the original fiberglass is. I think I uploaded some photos in a previous post.
Doug

[Donald H.]

Re: undercoat removal

I agree with the other posts. I just finished the underside of my 60 restoration project. The hardest stuff to remove was the undercoating in the wheel wells. I used Captain Lees Spra n Strip, laquer thinner, brake cleaner and a small metal putty knife. For final cleaning I used the red Scotchbrite pads on the stripper and laquer thinner or acetone.

What made it much easier was having the body off and up on it's side. Before and after photos attached.

Don

[Dan P.]

Re: undercoat removal

The easiest and cheapest way is diesel fuel in yard spayer.It is messy but will work. Take you time . Spray it ever day tell the undercoat gets soft.You may want to put one of the blue tarps down and the lay at news papars to catch the run off. If possible soak it real good and cover it with plastic and let it set.I did the underside of the hood like this . Let is for a week . Most of it came right off with a bondo spreader . Then power washed the rest.The trick is to let the fuel desolve the undercoating.Scrape it and if there a bunch left soak it again.

[Lou C.]

Re: undercoat removal

Bob, I use a heat gun and a metal putty knife to get the heavy stuff off.
Lou

[Bob M.]

Re: undercoat removal

I want to thank everyone for their reply. I was hoping for a easier way to get the tar off. I guess I'll keep using the heat and putty knife method.