The Stovebolt Site Forums The Shop Area Paint and Body Shop Primer over body filler

I've been doing some touch-ups with some body filler and it's coming out really nice. I plan on using finer grit sanding soon, but for now it's sanded with 120 grit. After I primed it, I noticed real fine pitting in the filler...is this normal? Also, what's the best primer to use over filler? It looks like the primer I'm using now kinda soaks in to the filler.
Thanks in advance!

Checked the photobucket---- wow yeah --- I'm surprised the finish wasn't covered in hairs--- never mind soaking into filler----

Ditto on that photobucket! How about I come out to help you finish your truck, say around the peak of the rut. As far as the holes in the putty, I would smear on some glazing putty or similar product that is made for filling these pores. You will like how much easier it is to sand than body filler.
Carl

Dag-gone, I forgot about the photobucket pictures. I put them on for a 1 time showing and forgot about it. Come out anytime, I have a spare bedroom in my log house set up just for hunters.
That glazing putty, is it real thin like molasses? A friend of mine mentioned to use a primer with poxy...I never heard of it.

mummdogg

The pits or air pockets in the primer vary with the grade and brand of primer as well as the way you mix it. They are caused by trapped air mixed into the filler.

The problem with spot putty or glazing putty is as you wipe it on with a putty knife or squeegee, a tiny bubble of air can get trapped in the pit and when you sand it down the pit can reappear.

Get a can of "filler primer" or "sandable primer".

Spray 2-3 coats to build up the surface. It tries fast so wait 5 minutes between coats.

When it is good and dry get a bucket of warm water and 400 or 600 wet/dry sandpaper. Keep the surface wet and dunk the sandpaper often.

Sand right down to the filler. The only primer left will be in the pits and scratches.

Repeat until the last coat of primer is smooth and free of pits and scratches without sanding through to the filler.

Put on a coat of "primer sealer" before final paint. It will keep the paint from soaking into the filler.

I don't do it that way, but that will work eventually. High build primer won't fill the pits very fast and you will priming, sanding, priming, sanding... a lot. Everyone does things a bit different based on experience and what works or feels comfortable to them. The "holes" in the plastic filler are caused by trapped air in the filler or from using too much hardener.

I don't worry about the pits until after the first coat of primer. With primer, they show up like a sore thumb. I scotch brite the primer and use glazing putty to fill the pits. Yes, sometimes the trapped air causes the putty to not fill the pit, but most of the time, that is not an issue. I then sand the primer with 220 grit before apply second (and most of the time final) prime coat. After second prime coat, I look for the imperfections again. Use more glazing putty and final sand with 320 grit. Next comes sealer and/or final paint. Done.