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Pro-Mo
09-07-2011, 04:40 PM
My only attempt ever at wet sanding primer before painting was a failure. The base didnt want to stick. I used 1500 dry then 3000 wet. Too fine? Or is wet sanding primer just a farce?

Being in collision I dont get the opportunity to dabble in custom stuff. I have done more custom painting on the side than I have in seven years at work.

Please school me lol

I may add the the primer I wet sanded was on a set of custom wood speakers. Although it was the same primer used on our cars.

bhcustomdesigns
09-07-2011, 05:01 PM
1500 and 3000 is way to fine of grit to use before laying base those grits are used after the car is painted for color sanding and buffing 500 or 600 grit is good for the final sand before spraying basecoat.

astroracer
09-07-2011, 06:35 PM
If you are shooting BC/CC 800 is good. Do not spray primer over anything finer then 600. I like 400 at the most... primer needs a "tooth" to adhere as it is a mechanical bond. Chemical bonds, like BC/CC, do not need the tooth for adhesion.
Mark

elitecustombody
09-07-2011, 08:26 PM
Let me get this straight, you do collision work and yet have no idea of the elementary basics on prep & refinishing? What do you actually do at work?

Anything finer than 320 grit prior to primer is prone to failure,peeling,chipping,e.t.c.
If you're planning on applying some sort of topcoat over wetsanded primer and want that paint to stay on ,do not use finer paper than 600.
Also keep in mind that many primers will absorb moisture like a sponge,if exposed to moisture for long period of time, so make sure that you have epoxy primer under your surfacer primer.

Pro-Mo
09-08-2011, 04:10 AM
Let me get this straight, you do collision work and yet have no idea of the elementary basics on prep & refinishing? What do you actually do at work?

The question was about wet sanding primer, not before. How many collision shops actually wet sand primer? Probably not many which is what lead me to make this thread. I guess if person doesnt know one seldom used step he doesnt know " elementary prep and refinishing "

Anything finer than 320 grit prior to primer is prone to failure,peeling,chipping,e.t.c.
I know this
If you're planning on applying some sort of topcoat over wetsanded primer and want that paint to stay on ,do not use finer paper than 600.
This was all I was looking for
Also keep in mind that many primers will absorb moisture like a sponge,if exposed to moisture for long period of time, so make sure that you have epoxy primer under your surfacer primer.
We do not leave a car in primer long enough to worry about that. But thank you.


I may add the only time ive ever sanded primer with anything finer than 600 was on those speakers.

Thanks for the info.

Pro-Mo
09-08-2011, 04:12 AM
1500 and 3000 is way to fine of grit to use before laying base those grits are used after the car is painted for color sanding and buffing 500 or 600 grit is good for the final sand before spraying basecoat.
Thank you