Hey guys I started sanding down the car for repaint and the guy before me had a new paintjob but theres like 4 layers of paint and primer altogether to sand through. Took me about 2-3 days to sand down the whole trunk on my integra coupe. Ive been using 80 grit with the DA sander and then I went down to 36 but it still takes a long time to get to the metal. Is there a faster way?

Also I was wondering if I just needed to sand it down to the factory primer or does it have to go down to the metal. I just want to do a really good paintjob later. Thanks.

 

i'd only sand it down to factory primer... not bare metal... a really good paint job means correct prep work, and masking.
factory primer has the best adhesion and corrosion protection

 

Oh ok i thought so...would it matter if there was some bare metal and some spots of factory primer?

 

Don't paint over bare metal without priming it first.
Primer is there to protect and to stick.

 

Yeah, I kinda figured. But I guess I will just sand it down to the factory primer, then when I'm finish we will spray another primer (not rattle can) and then go from there.

 

paint remover ($50 a gallon) and a pulley knife

 

Would that take the primer off too? How would i put that on the car without getting it all over the place.

 

Yes it would...Don't use that stuff. You only need to scuff the top layer, not remove it all. Since you have so many layers, it might be a good idea to get through them all, but have fun getting 36grit scratches out. haha. Any bare metal spots need something like an etching primer or epoxy primer (best) before your regular primer.

 

mine was the same way, but 3 layers... took me 3 weeks off n on. you'll get there man

 

Damn that means more **** to buy. Do you think the 80 I'm using is okay, or same as using a 36 anyways?

 

I wouldn't go below 80, but that's me. You either do the work now, or do the work later filling the scratches with glazing putty.

 

I'll stick to 80 then. I hated seeing the 36 scratching up the metal. made me cringe. So sanding down to the factory primer then iguess. I'm pretty sure i'll have to use epoxy primer now because i have a lot of scratches from the 36.

What do you recommend sanding for the plastic bumper, sideskirts and rear bumper? I think i bought 180, and was going to handsand it. btw i appreciate the help.

 

Yeah 180 is perfect....that's what I used for mine, and then used a primer-surfacer afterward. That filled in all the scratches nicely. It doesn't hurt to check the information sheet for the primer you'll be using also; it should recommend what grit to use before spraying it.

 

Oh okay nice. Will do. Thanks.

 

I had almost this same issue on a cutlass that we did as well as my civic, we took our big 7"buffer put a grinding pad on it and grinded it all down to bare metal, (do this on metal only on all plastics use a DA with 180 then 160) then primed and wetsanded with 360 then painted, if you have to sand the whole car down anyway you might as well do it the fastest way possible. and if you use a good etching primer it will fill all the grinder marks as long as you dont go apeshit with the grinder, what the primer doesnt fill sand with a DA with 180 grit then reprime.

 

Problem there is that by taking off the factory primer, you're stripping off a very effective corrosion resistant layer. Yeah it's fast, but etching primer has got nothing against OEM primer. If you are going down to bare metal, there are extra steps to be taken to get it as close as possible to factory corrosion resistance. You're just better off leaving it on there when possible. A little bit of bare metal here or there isn't the end of the world, but there is no reason to do it to the whole car.

 

Maybe its just me but I would prefer not to have to DA my way through 4 layers of paint when I could get a grinder and go down through all of it to bare metal an prime it again in half the time, and if you use a GOOD primer and a good painter it will give you the same finish

 

I forgot to ask, is it gunking up your DA pads?

 

No not really. If i use it long enough it does get gunked up on the outside edges. When I use a sandingblock for body filler work then thats when it gets really gunked up.

 

Yeah, I dont want to take the factory primer off, thats where it takes the longest, trying to get it all off.

 

use aircraft stripper! then apply a coat of e-coat primer followed by 2 coats of high build primer. block that down with 180 and a block, then if needed do your body work and re-prime. 3 coats of paint, then a 4th coat=complete wavyness!!!!

 

I am agreeing with bakertime on a lot on this.

There is no need at all to strip down to bare metal. Like bakertime said, it removes the factory ecoat which is the best corrosion protection your getting for your money.

I have repainted a few friends cars and all I did was scuff everything with a soft pad on my DA (so I don't create waves) with 240. Than 320. Than seal, paint, and clear. This is all of course after body work is done. But if a panel is straight and good, I just did those few steps.

Don't create more work that you have to. And take your time, because once you spray the clear, its a bitch to go back and redo work and fill scratches.

 

Yep...and for you guys that strip the paint off, I sure as heck hoping you're using epoxy primer when you're done, because that is the only way you're even going to get close to factory protection. Yeah, sanding takes a long time, but that's why body work is expensive. If there was a faster, better way, then the pros would be using it. SOMEtimes it's appropriate to strip to metal, but rarely.

Keep on truckin' srok! You'll get there...and you'll be glad you spent the extra time in the end. I sanded my whole car by block and paper, no DA for the exception of getting to bare metal for filler. It takes longer, but it's a lot easier to make a mistake on a DA then it is on a block. Also, you don't have to get it all to factory primer...you really only have to scuff it. However if you're concerned about the paint buildup, I would just go down to when you're seeing the last color of paint and some primer. It's not an adhesion problem for the paint to be sprayed over existing paint.

 

Yeah thanks for the advice. I'm still barely on the driver side door. I'm using DA with 80 still and I will go back and use the epoxy primer when I am done. I started at the trunk with all to bare metal before I posted so I decided I'll just keep doing the same thing all around the car. How far did you guys sand down when you were doing the door jams and tight spots like that?

 

With that approach, I'm pretty sure that you need to Epoxy prime each panel immediately after you're done. It will start to rust immediately on a microscopic level. Also, I think you have to be extremely careful to not touch the bare metal with your skin. Point is, I would again recommend that you NOT use that method. But if you insist, I would do some research on epoxy primer and covering bare metal. I'm no pro...I just research a lot!

For the jambs I just scuffed really well with a red scotchbrite. You can use sandpaper too, but the scotchbrite lasts longer and is cheaper for how much paper you'd use.