Paint sanding question

[dodgemahal]

I'm not sure if I'm in the right sub-forum, but here goes:

I haven't prepped a ride for painting in a few years so I forgot something. How do you keep from cutting through an edge while sanding a fresh coat of paint? By edge I mean something like a character line that runs the length of the vehicle. My 73 Dart has several of those. If I'm not careful it's easy to sand down to bare metal.along that "peak". I think there's a technique but don't remember what it is. Thanks.

 

[Oldmanmopar]

Use a sanding block or board and only sand the flat surfaces and never cross the body lines, After this is done you can go over the body lines lightly by hand to scratch these areas for adhesion for more paint or go straight to buffing . You can run a piece of tape on the lines to make or keep them straight. But never cross the lines while sanding.

 

[1MeanA]

Why are you sanding a fresh coat of paint? Are you doing a cut and polish on a base/clear paint job?

 

[dodgemahal]

Good info Oldman! I use blocks but I probably should switch to a hard board near those lines. Thanks.

To onemeanA: I'm going to shoot with an initial coat of epoxy. I always sand that with 400 grit, then apply a skim coat of filler where I need it, then more epoxy and sand once again. I know we all go about it differently but that's how I do it.

 

[1MeanA]

Typically filler needs a coarser grit under it. After epoxy most people spray a 2k primer or high build primer which is much easier to sand than epoxy. Block it 180, reprime and then sand 320/400 then 600 depending on whether your going to paint or sealer.

 

[dodgemahal]

Typically filler needs a coarser grit under it. After epoxy most people spray a 2k primer or high build primer which is much easier to sand than epoxy. Block it 180, reprime and then sand 320/400 then 600 depending on whether your going to paint or sealer.

Thanks for the advice. I'll try that. I'm still learning.

 

[1MeanA]

There are lots of good resources out there…YouTube, forums, FB, etc. of course you have to figure out the knowledgeable people. I go to autobody101.com , spiuserforum and a few YT channels like Paint Society

 

[harrisonm]

Typically filler needs a coarser grit under it. After epoxy most people spray a 2k primer or high build primer which is much easier to sand than epoxy. Block it 180, reprime and then sand 320/400 then 600 depending on whether your going to paint or sealer.

TOTALLY what he said. You will regret sanding with 400 and then applying filler. 400 will not give the 'tooth' required to give the filler something to really stick to.

 

[dodgemahal]

TOTALLY what he said. You will regret sanding with 400 and then applying filler. 400 will not give the 'tooth' required to give the filler something to really stick to.

I guess I've been lucky then......no problems with past projects, but I will heed your advice. It makes sense and you guys know better. Thanks.