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Fri May 23, 2008 5:08 pm

Hi was wonder if it ok to sand the first coat of epoxy primer. I have some trash in it. I was hoping to sand it out then shoot another coat of epoxy primer.

thanks

Sat May 24, 2008 6:50 pm

Ok I just wet sanded the kirker epoxy primer ENDURO PRIME back down. I shot another coat and got the same results. I have a texture like finish. Like the paint is splatter one. I was wondering if i need to reduce the primer to get it flow correctly?

any help will be appreciated.

Barry

Sat May 24, 2008 7:56 pm

What pressure are you shooting at & what size needle in your gun? Try about 20psi (HVLP) with a 1.8 tip

I wouldn'y worry too much about a slight textured finish. 400 wet/dry can remedy that problem.

Sat May 24, 2008 8:59 pm

Im shooting it with a hvlp turbine. I think the needle is for thick material. 1.3 or bigger.

Sat May 24, 2008 11:04 pm

Epoxy primer can be sanded and, in fact, it has to be scuffed up if the primer surfacer isn't sprayed over it within three days of shooting the epoxy primer, and another two coats applied before spraying the primer surfacer.
Normally, there should be eight to ten psi at the air cap of an HVLP gun. I don't know about a turbine gun, though. What is it?
For the epoxy primer that I have used, there is a two to one ratio, epoxy primer to epoxy primer catalyst. Acetone can be added up to ten percent.
The pot life is eight hours at 70 degrees F.
Read the product information sheet that you got with the primer, since the information may be slightly different.

Sat May 24, 2008 11:41 pm

HI its kirker epoxy primer. It is a 1 to 1 ratio.

So I can add some acetone to thin it out some so it will shoot smoother?

Barry

Sun May 25, 2008 1:40 am

Mine is Omni; you need to get the product information sheet for your primer from your paint dealer to find out what to use to thin it out.

Mon Jun 09, 2008 1:27 pm

Campy - I just shot ppg shopline (omni) epoxy primer this weekend... came out super textured. I had the same problem as Chance.
I was wondering if your shopline (omni) comes out the same way... I was using a devilbiss gun with a 1.8 tip 30psi... no acetone... I tried different settings on the gun, but no luck in getting a finer spray...
From what I understand, ppg epoxy is very hard to sand and clogs the paper instantly (I'm going to hit it with sandpaper tonight and see what happens). I also can now see a couple small spots I'd like to put a little filler on... o.k. to scuff up the epoxy and put filler overtop? And then epoxy over it again to seal it?

Tue Jun 10, 2008 12:17 am

Was your car ready for the top coat or had you just applied the epoxy primer to seal out moisture during storage?
My Omni epoxy primer was smooth as heck when I sprayed it over the interior in my bus. I had used one of my old Binks suction guns. To be legal, I had to use my Devilbliss HVLP gun when I did the outer body in a rented paint booth (epoxy primer, then top coat), and there was orange peel. I color-sanded it but some little spots of the grey epoxy primer came through (orange peel on primer). I had to scuff up the top coat and re-paint it. The HVLP gun did not atomize the paint as well as my sunction gun.
You can scuff up the epoxy primer (cross hatch pattern) and put filler on it, as long as the paint is sticking well. Personally, I always put filler on bare metal, scuffed up real well using 40 grit sandpaper because there is one less variable.

Tue Jun 10, 2008 5:25 am

All PPG products can be reduced with thier DT or Global reducers. Im sure you can also reduce this Kirker stuff you guys are spraying as well, however I would not just go to Lowes and buy Acetone. I would use thier products. You just never know what kind of crap can happen when you mix and match paint systems.

Also EVERY hvlp gun I have used required more air pressure than what was stated in the instructions.

Tue Jun 10, 2008 9:53 am

I might agree that the older high pressure gun might have atomized this paint better, but i haven't tried it... I would have probably gone thru 3X the paint as those guns throw so much paint in the air it is ridiculous...

I had it stripped to bare metal and wanted to get some good primer on there to seal it up... not sure when I'm going to do the topcoat... still working my way around the van making repairs... also, from what i understand it is best not to thin the first coat going on bare steel... i thought it was best to just use the paint and hardener... and if another sealing coat is needed, thin that...

As far as the body filler goes... now that it is painted, i realize i can see all of the original spotwelds marks where the inner strengthener was welded to the inside of the panels on each side of the van... :roll: so i'm not looking to add a ton of filler... i might even be able to build it up with primer and sand it smooth, but a skim of filler would be much easier...

Sat Jun 14, 2008 1:32 pm

why epoxy primer that stuff sucks and it is too hard to sand. why not a self etching primer like dupont variprime nason has an etch primer too this stuff lays out like glass and is easy to work with. eveh helps with some of the pitted rust. two medium coats let dry scuff with red pad then follow with good two part urethane primer then we are ready to blocksand for days.