Which is best sander for sanding down the body of the car for fast paint removal and the smoothest finish after stripping the paint? I've got most of the car stripped with a razor blade but there are some tough areas where the paint does'nt come off as easy. Is a orbital sander, or a random orbital sander the correct one to use? A standard non orbital vibrating palm sander is not cutting it. I am using 80 or 100 grit for paint removal and then 150 for smoothing it out prior to priming it, is the correct?

 

kdlp

 

Perhaps a real paint and body man will jump in here with an informed and inteligent reply, but for my .02, I never use any power sander on bare or near bare fibreglass, unless I am shaping a large repair area. After I strip a car, I wet sand by hand (with a block or sanding sponge) with 200 grit or finer.

Orville

 

It's hard to beat an air powered DA (dual action sander) for speeding up a sanding job. They are light weight and powerful. You need a moderately sized air compressor, however. There are electric versions available ( I think DeWalt and Porter-Cable have versions of these) but I can't vouch for how well they work.

The dual action comes from the orbital motion of the pad that also spins randomly as the sander is moved across the surface. For the final shaping and smoothing however, there's no substitute for hand sanding with a block.

 

The D/A sander can speed things up, but if you are not experienced and careful, you can kill the edges easily. Stay away from edges and corners, hand sand those. Don't get into the fiberglass, stop at the existing primer......

 

Why not give the razor blade method a try?

 

I would never use a sander to remove paint from a car especially a fiberglass one.

 

I have stripped most of the car with a razor blade already, and it works very well by the way. I just have some areas where the paint just will not budge with razor blade technique like it did on the rest of the car. These areas are going to have to be sanded in order to finish the job. I do not want to use stripper on these areas and have to deal with that mess, and if there is any surprise body work under the old paint, I don't want the stripper getting into the body filler and causing problems with the new paint job down the road.

 

You can get an electric one that is 70% as good as an air d/a as we call them. Ryobi makes one. Yes, don't grind your gel coat. yes, use 220 and only cut the paint. You can cut the paint until you get it really thin. Maybe then you want to go to paper and a block. When you get it stripped, you can fill in those gouges that the razor made. You may want to use some form of resin so that the glass is sealed. Been here, done this. Too much.

 

Before buying a tool try block sanding it with very course paper. The jitter bug is probably locking onto the paint and shaking your hand. Swinging it around might help but hand sanding might work also.

Besides you will have to block sand eventually

 

Yes, that is exactly what I'm looking to do, knock the paint down with the sander to where it's thin enough so that I can block sand it by hand. I didn't do to bad with the razor blades, not too many gouges or knicks to fill in that were caused by me. I did however find some that were under there already from the previous owners who had painted the car about 3 different times and probably did the razor blade thing. I also have 6 holes to fill in on the rear deck where I removed the luggage rack. They look good on NCRS chrome bumper cars but not on rubber bumper cars IMO.

 

block it ........ it's a bit harder but u won't have to re-feather it all again...... do 120 grit........ i used an orbital hand sander only for knocking down fiberglass that i layed for the bumpers......

b

 

going back through some post from a couple of days ago, and thought I would give my .02. I just got through doing the very thing you are doing. You cannot beat an air powered DA, as mentioned above. It is a good Idea to stay away from the edges. On those, you will just have to gut it out with a hand full of 80 grit. Use 80 on entire car if you want. I am sure I will get some disagreement, but I do not believe you have a "gel coat" in the truest meaning of the word. I believe they sprayed the inside of the mold with resin (what some people think is the gel coat), and then use a chop gun to spray in the "body".

Go to harbor freight, or somewhere similar, and get some small picks, they work great in the corners. Just scrape like hell, do not worry to much, don't dig to China, but you can go at it pretty good.

While you are at Harbor Friegh pick up a double scotch brite pad set up for a electric/air drill. These work great in area that the DA will not get into. HOWEVER, AGAIN, DO NOTTTTTTT USE THIS THING ON THE CORNERS, OR YOU WILL BE DOING BODY WORK. If you are worried about the corners get some masking tape(the good 3M stuff), and run it along any corner you are working, and work one side of the corner at a time, switching the tape when you get finished with one side. Then you will have to force yourself to work to that corner, never touching the "down hill (or uphill) side" from the side you are working.

About the gouges. DO NOT WORRY. Surfacer will fill them in, and it will be slick as glass (no pun intended). You can have your painter, or you make about two passes around the car with surfacer, and then block it, you will be impressed, and also quickly find your high and low spots.

 

i'm no pro, but i have worked for a few body men when I was in school and they would all agree that you have to block sand on glas. Ok to use a random orbital sander to take down repairs, but the risk of breaking through the skin, and creating flat spots machine sanding is not worth the the time savings. Burn through a couple times, and you will be longer than if you hand sand / wet sand with good clean paper.