wet sanding primer

[rjs53]

Was wondering if any of you wet sand your primer? I'm using a Matrix polyester primer sealer and am considering wet sanding, just because of the dust. I wear either a N95 or a half mask with cartridges, but was thinking the wet sand method might help the paper from clogging. I'm going to let the primer set another day before I start and though I would get some opinions. Thanks

[67swb72klb]

I don't wet sand till I get to 400 grit

[Elliot949]

I only wet block and any high end painter that is the way they do it...

[rjs53]

I've always wetsanded before, but usually wait till base is going on. Gonna try wet method from the beginning this time. I'll try a fender first in case something goes wrong.

[sick472]

I have done a few cars and have always used grey lacquer primer. Once the panel has had the body work 99% complete, meaning all the skim putty has been added, smoothed out, and a final thick layer of primer applied, it's then that I start the wet-sanding process (about that 400 grit mark that 67 mentioned). If I find some places that need some more skim putty then I will dry sand that work and prime, then back to wet-sanding. I suppose one could wets sand throughout the whole process, start to finish, but that's a lot of effort and mess to avoid using a mask.

[ls1nova71]

Originally Posted by rjs53

Was wondering if any of you wet sand your primer? I'm using a Matrix polyester primer sealer and am considering wet sanding, just because of the dust. I wear either a N95 or a half mask with cartridges, but was thinking the wet sand method might help the paper from clogging. I'm going to let the primer set another day before I start and though I would get some opinions. Thanks

I wouldn't wet sand polyester primer. That is for high build and can be a bear to sand with any grit that is fine enough to find a wet sand paper in. It also isn't completely waterproof, meaning it will absorb moisture. Block sand it dry until you get your panels straight, then apply a urethane primer over that and wet sand that.

Originally Posted by sick472

I have done a few cars and have always used grey lacquer primer. .

You can still find lacquer primer? I haven't seen that stuff, with the exception of spray cans, for years!

[sick472]

Originally Posted by ls1nova71

You can still find lacquer primer? I haven't seen that stuff, with the exception of spray cans, for years!

Martin Senour (Napa) still makes it and so does 5 Star Extreme (sold at Bumper to Bumper) and Nason. Some call it Acrylic Primer or Acrylic Lacquer Primer. I'm pretty sure it's all the same. My Bumper to Bumper still sells acrylic enamel paints - mixed to match!

[70CHEVYBB]

i stopped wet sanding a long time ago. probly a personal preference but then agian im not a body man. my 72 after i got it home from the paint shop and no wet sanding

[rjs53]

Not wet sanding the high build ply primer, wet sanding the poly/sealer. Dont ask the difference because I don't know myself. The high build poly is mixed with a small amount of activator. While the other has the normal activator and reducer , but according to the tech sheath it can be wet sanded. Personally I like the wet sand method. I have a mess on the floor I can mop up, the dry sand has dust everywhere and covers everything. Just wanted to know what others do or have tried.

[ls1nova71]

Originally Posted by sick472

Martin Senour (Napa) still makes it and so does 5 Star Extreme (sold at Bumper to Bumper) and Nason. Some call it Acrylic Primer or Acrylic Lacquer Primer. I'm pretty sure it's all the same. My Bumper to Bumper still sells acrylic enamel paints - mixed to match!

That's interesting, just haven't seen it in a long time, not that I have been looking for it! LOL! I went to urethane primer years ago and never looked back, lacquer has way too much shrink back for me. Having sand scratches reappear after paint is a real bummer.

Originally Posted by rjs53

Not wet sanding the high build ply primer, wet sanding the poly/sealer. Dont ask the difference because I don't know myself. The high build poly is mixed with a small amount of activator. While the other has the normal activator and reducer , but according to the tech sheath it can be wet sanded. Personally I like the wet sand method. I have a mess on the floor I can mop up, the dry sand has dust everywhere and covers everything. Just wanted to know what others do or have tried.

Oh, ok, I have never used Matrix, but I think you just have your names mixed up. I am going to guess its polyurethane, not polyester. I would definitely wet sand it before any top coat is applied, be that color or sealer. sealers are generally not sanded, but rather applied right before the top coat goes on.

[67chevemall]

Bucket of hot water and heavy rain is the only way to sand. 220 then 320

[rjs53]

Originally Posted by ls1nova71

That's interesting, just haven't seen it in a long time, not that I have been looking for it! LOL! I went to urethane primer years ago and never looked back, lacquer has way too much shrink back for me. Having sand scratches reappear after paint is a real bummer.


Oh, ok, I have never used Matrix, but I think you just have your names mixed up. I am going to guess its polyurethane, not polyester. I would definitely wet sand it before any top coat is applied, be that color or sealer. sealers are generally not sanded, but rather applied right before the top coat goes on.

You are correct sir, epoxy.

[71 K20 in SD]

I am currently painting my 71 right now and have had some great success so far ..wet sanding is time consuming and puts water on possibly unfinished body panels(exposed steel) which later might expose a rust problem later
I am finishing up my Truck this fall and have found that a good final paint finish does not require a wet sanded finish. I use urethane primer my final sanding on the primer is done with 320 sand paper, then a final overall scuffing or smoothing is done with my Scotch-Brite pad.

I so far have finished about half my truck and and it looks amazing..I do plan on wet sanding and buffing...but not prior to final paint and clear coat