Excavating bondo... any easier way?

[Swede958]

So I found out that a media blaster will not normally be able to remove the bondo on a car. That being said I started digging into my car last night just to see how much bondo there was on the car. Apparently, alot.
I think there is about 1/8" of bondo on d/s quarter panel, and at least that much on the entire taillight panel. Basically it's enough that when you are down to bare metal and rub your finger over the ridge- it feels like a worn all-to-hell-and-back brake rotor. That much.

I stripped the outter paint off first with a chem stripper, that got that layer off, but didn't really scratch the, what I believe to be, epoxy primer underneath. So I took my DA sander to it and started to see some results, but what still going slow. Out came the grinder with a wire wheel. That went a bit faster, but would bite really hard into the bondo. Tried a flapper wheel, and that seemed to work the best, but was still kinda slow. Is there a faster way? Should I just use a griding disk and watch out for the metal underneath or am I just do in for a long long time of flapper wheeling it?

 

[n8rsk8r]

yeah a big grinder
it will go right through it and fast. Wear a mask, the stuff stinks. One of those BIG 9" grinders

 

[5.0ina66]

dump some muratic acid on the bondo and leave it for 15min covered with plastic wrap? never tried it, just a crazy idea.

BTW: in the early days of bondo they ground it like they did lead, and found out that DUH, bondo dust screws up your lungs....wear a mask! (that's why they started sanding)

 

[Cobra5.0Jeep]

When we found bondo on the front driverside fender we just used a body hammer and hit on it from the otherside, the bondo cracked up and then we just pulled it off. We're not done but it seemed to work good for us. We also used a grinder for some of it.

 

[302 coupe]

use an angle grinder with a knotted wire brush. Works great for removing bondo, paint, rust, and skin from your hands/arms. Use with caution, wear dust mask, safety glasses, and leather gloves, seriously. It works great though, removes everything quickly while not damaging the metal.

 

[Silver66FsBk]

the way I removed the bondo that my car had was to use a torch either
nap gas or butane and start the heat the bondo up and as its getting hot
start to peel it off with a pudy knife.

 

[zookeeper]

I use a body grinder and a green 3M bristle disc. They are made of some sort of abrasive material and work great without the risk of damaging the metal underneath at all. Your local paint store should be able to get them for you or try Eastwoods, I think I paid about $20 each the last time I bought them, and one disc will do about 1/3 of a car.

 

[Swede958]

thanks everyone, I'll give some of those a shot in the morn

 

[iskwezm]

i use a 50-80 grit on a sander/grinder, but the torche works very well too.

 

[stangonline]

What did you have your car blasted with? There is a fab shop here that has their cars blasted with walnut shells and from what I saw, it removes everything except the metal. This is what I was planning ondoing.

FYI, its common to have a "skim coat" of bondo on a lot of the car. My 67 has original sheetmetal, but to smooth out some dings and such, they skimmed most of the car. LIke yours, a lot of my car has at least 1/8th bondo on it, but when I remove it manually (used wire brush so far), the metal under it is just fine....so someone made a lof of work for me...arg.

Jeff

 

[bnickel]

What did you have your car blasted with? There is a fab shop here that has their cars blasted with walnut shells and from what I saw, it removes everything except the metal. This is what I was planning ondoing.

FYI, its common to have a "skim coat" of bondo on a lot of the car. My 67 has original sheetmetal, but to smooth out some dings and such, they skimmed most of the car. LIke yours, a lot of my car has at least 1/8th bondo on it, but when I remove it manually (used wire brush so far), the metal under it is just fine....so someone made a lof of work for me...arg.

Jeff

it was very common in the 70's and 80's to put a skim coat on the whole car before painting it, that was before they had really good filler primers.

 

[Swede958]

I haven't had it blasted yet... was under the impression that media blasting wouldn't be very effective at removing the bondo.

Yeah, from what I can tell the metal underneath on the quarter panel is fine. The bondo appears to be two very think skim coats. One dark shade one light shade. I didn't get a chance to work on it really so we will see.

 

[C0V3R]

3m stripping pads work well ... theyre like a tangle of wire with coarse grains glued onto the wire. Work quite well.

 

[unrealmach1]

I had my car media blasted and they can remove the bondo or leave it. I had my car stripped to bare metal. Most good media blasters clean your car in stages using different types of material to work down to bare metal and get the car ready for primer. My car was painted several times and had quite a bit of bondo for no reason that I can see. At first I tried a grinder, but that took a long time and was a mess. I found a media blaster to do the entire car for $600 and it was the best money I ever spent.

 

[68restoman]

A propane torch and a putty knife is the way to go. Just heat up the bondo until it starts to bubble and scrape it off like butter...

68Restoman