PierreOlivier

I started removing the paint, etc. on my 65 convertible. I knew that the car had been "tapped" in the rear but have discovered that there must have been a sale on bondo at the time. I have been using a heat gun and razor blade scraper. The problems are:

1) Taking a long time
2) Tend to dig in even when being careful
3) There is some kind of dark material between the bondo and fiberglass; no idea what it is

A few questions:
1) Will plastic bead media blasting remove the bondo?
2) Any idea what the dark stuff is?
3) Faster/safer way to remove the bondo?

Here are a few pictures:

zwede

Had a similar mess in the front of my '71 and decided to just replace those panels. Odds are once you finally get all the bondo off, the panels are so damaged and patched they're not usable anyway.

DUB

You have to use common sense and keep an eye on what you are doing. I would also look at the backside of the panels that have all this bondo in them and see what they look like. If they still look intact...the panels can be repaired.

It will boil down to what you want...what you are willing to do and how much time and money you want to invest.

DUB

PierreOlivier

Thanks Dub. What is your tool of choice for grinding?

DUB

I use several types...it all depends on the surface area I am trying to grind. Usually my "go-to-tool" is the 3 inch Rol-loc grinding discs. I use 24, 36 and 80 grit. I also have the 8 inch pad that uses the 8 inch (duh) adhesive backed sanding discs...and I use 36 and 80 grit on it.

A couple of tips or tricks. Using a grinder is much like driving a car...when driving a car...you do not have to have your foot to the floor and revving the engine. The grinder is the same way. Controlling the rotating speed, pressure and travel speed will make you less prone to a screw-up.

Also within reason...not allowing the grinder to wind up to top RPM...will also save you sandpaper/discs and not wear them out prematurely.

Lastly, if grinding at a good moderate speed...try to have you grinding disc rotate so your "bondo" is being ground on in a way that the "bondo" is being sent to the ground....instead of going straight up in your face and in the air. It can make clean-up easier and not having dust all over the place. YES...I know...you are going to get dusty..but if you try it...you will see that a lot will hit the floor and 5 feet away there is no dust cloud. I set up a vacuum system ...but that is just me on big grinding jobs.

Just go slow and be watchful. Like I wrote before...if the underside/backside of the panel in this area of bondo is good...the panel can be repaired...but it will be up to you if you do or not.

DUB

PierreOlivier

Great advice. Thanks Do you use air powered grinders or electric?

Jack605

Aircraft paint stripper will soften up the filler and you can use a razor blade to peal off about a paper thickness each swipe, takes awhile but it will come off clean.

PierreOlivier

I am using both - stripper and a heat gun. Heat gun seems to work better on the bondo. It appears that most of the panels from behind look OK so I am hoping they can be saved. I will post pictures from underneath tomorrow.

DUB

I use both...electric and air powered tools.

DUB