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Fri Feb 23, 2007 9:52 am

I need to know what grit sand paper to use to go all the way down to the metal on my '59 Beetle. I have most of my replacement body parts now, but I need to sand it all down to see if there's anything hiding I need to replace. The PO repainted the car, so I don't know how much is underneath as far as primer, og paint etc. I just don't want to use something too harsh that will damage the metal. Thanks.

Fri Feb 23, 2007 10:51 am

(I just had to post a reply because you live in a Charleston :D , too.)

I would consider abrasive media blasting such as aluminum oxide to take the paint (and any rust :wink: ) off of the metal.

Fri Feb 23, 2007 12:09 pm

I used my random orbital sander with 80 grit sandpaer to knock off the old lacquer, then something like 180 to 220 grit sandpaper to get through the layers of primer to the original paint.
You can use a low grit sandpaper to save time but before you get to bare metal (primer), switch to a higher grit sandpaper so there won't be deep lines in the metal (180, then 220).

Fri Feb 23, 2007 2:33 pm

even though a lot of hobbyists on here will disagree, if i'm stripping a car without the use of chemicals i prefer to rip the paint down with 36 grit paper on an 8" orbital sander (aka mudhog), don't use a sander/buffer they are way to aggressive. after that you can get out all of the 36 scratches on the metal with 80 grit on the same sander or a da sander, then use a da with 180 if you prefer. 80 grit scratches in metal are not as harsh as 80 grit scratches in paint. i've found this method faster and less messy than chemical stripping. you still have the dust do deal with, but for me it's a good trade off.
there has been debate on this method here before when i mentioned it, and i don't wanna start one again. it works with good results, if you don't like it, don't do it.........
good luck with whatever method you choose.

Sat Feb 24, 2007 2:34 am

I used 36 grit with a DA on mine and it did a really nice job and did not mess up the metal. just don't hold it in one spot for long

Sat Feb 24, 2007 10:22 am

36 grit? Wow, that's like killing a fly with a shotgun isn't it? I would say anything over 80 grit is bound to remove alot of metal along with the paint. 36 grit is more of a heavy rust or first-stage grinding disc for welds. I don't think I would take it to a painted surface.

Sat Feb 24, 2007 11:50 am

36 grit on a da or mudhog removes no metal unless you sand the same place for minutes. trying to strip an entire car with 80 grit would take so much more time and you'd burn through so much more paper. 36 grit will etch the metal up pretty good but you can get rid of the scratches with 80 grit if you want before you prime.
if you used this method on a modern car with todays crappy high strength steel, yes it could turn into an issue if you are not careful.

Sat Feb 24, 2007 12:23 pm

I used 80 grit sandpaper to get down to bare metal on the roof of a bus and it did take forever. I'm more careful when I am not taking a panel down to bare metal, which is why I start out with 80 grit, in those cases. Since you want to remove all of the paint, try using 40 grit until you just begin to get down to the primer and have scattered splotches of top coat left, then go with higher grit sandpapers. There is no need to be in a hurry to remove the last few coats of primer and have deeper scratches in the sheet metal.

Sat Feb 24, 2007 7:37 pm

yea 80 works fine for me too..

Sat Feb 24, 2007 7:41 pm

i agree 36 grit is *not* too harsh to go to bare metal as long as you are using an orbital sander(DA, Jitterbug, even orbital electric)....36 on a standard "sander"(not orbital or dual action) would indeed be much like a grinder...

Sat Feb 24, 2007 7:49 pm

Also, a SMALL amount of abrasion on the metal will help the primer stick. I usually like beadblasting for that reason- it roughs up the surface just a little. You can sand your bare metal with 80 grit as well.

Tue Feb 27, 2007 8:03 pm

Use a mudhog or sander buffer that has variable trigger with adjustible speed. I use a Dewalt set to 1000 rpms the trigger lets me go slower about 500 rpm. I used Norton 80 grit go back and forth left right diagonally and up and down this will bring the entire panel down at the same time and not get it hot. When I get to the original primer if there are no dents I will switch to 150 grit on the mudhog or da. You could use the mudhog for the 80 grit, I just don't like to hear my compressor run. If it needs body work I will do the metal finishing when I get to the primer and continue using 80 grit to see the highs and lows. sand blast any rust and metal prep all bare metal. I used dtm primer or two part self etching primer to protect the bare metal.

Tue Feb 27, 2007 8:57 pm

I forgot this, If there are many coats of paint I used to use my steam cleaner and get the non oem paint to peel off saving lots of time.