The Stovebolt Site Forums The Shop Area Paint and Body Shop Frame painting: Por15 issue

Hi All,

So after months of work cleaning up the rear half of my AD truck frame, last Friday was the day to apply some paint. I applied 2 coats of Por15 and then applied 2 coats of the Por15 Top Cote (gloss black UV protected).
I have used Por15 before and know what it is like but I have never used the Top Cote before. After I applied the 2 coats of Por15 I wish I could have just stopped there, the finish was fantastic. The paint really just smoothed out with no brush marks.
I let it dry up to where it was tacky and applied the Top Cote. The first layer went on OK but the second layer seemed to not go on as well. By this time it was already about 7:30pm and it was cooling down. The second layer seemed to show the brush marks. The results being that when it dried, I can know see all the brush marks. It looks terrible, especially since I used the gloss top coat and it reveals everything.
So my question to you all, does anyone have any suggestions to fix this? Can I rough up the Top Cote with 3M pad and paint over it? What did I do wrong, was the temp to cool for the last layer? I am disappointed but would still like to fix it. Does the Top Cote not smooth out like the Por15?

Thank.

RC,It sounds like your Top Cote was possibly applied when your second coat of POR-15 wasn't quite ready.
There's a fine line between too dry versus too wet.
The cooler evening temperature may have slowed the drying time on your second coat of POR-15.


The solvent content may well have been too much for the undercoat causing the brush to drag too much.
So the brush marks might actually be in the second coat of POR-15,rather than the Top Cote.

I know how tough this stuff is,all I can suggest is to let it cure for a couple of days,then try a test area with different grits of sandpaper until you find one that will knock down the brushmarks and try to re-coat the area.

Alternatively you could try contacting the manufacturer for their input.

Good luck.

sanding por doesn't work in my experience with the product. as said before, sounds like you didn't let it dry enough. when painting anything, patience is key. you may try to let it cure for a week or so and try to apply one more heavy coat and see if it will "fill" and look smooth.
best of luck

daren

top coat does not self level nearly as well as the por15 does. Ive had the same problem, wishing I had just stopped with the por15. The top coat works really well when sprayed, ive tried both regular guns and airless type. give it a try it might with a few coats hide the brush marks

I think you guys may be right. The Por15 may not have been dry enough and the Top Cote drag into it. I started painting pretty late (2:30) and probably should have waited for another day but I already had taken a day off of work to get this done. It took me over five hours to do it and I was rushed for time in the end. Now is how do I fix it. I will try and give the manufacture a call for some advise. I like the idea of spraying on the Top Cote but I am also wondering if I ruined my Por15 layer. Does the Top Cote have to be thinned out and does the Top Cote contain the isocynate (sp) in the paint?

rc,I think your POR-15 should be OK,it takes nothing short of a nuclear explosion to mess that stuff up!

I'm not sure about the chemical composition of the Top Cote but a word to the wise,if you are using any POR product a mask is highly recommended.
Isocyanates or not that's some nasty stuff to be breathing!

Don't ask me how I know......

Hey Jockbolter50,

I was using an air mask when I was applying the Por15 but if I do not have to with the Top Cote I would rather not wear it. It was very difficult climbing up and over and around my frame wearing the mask. Next morning I was beat!
I took a look at your website. Great truck and garage. Your frame looks great, Por15 I take it? You are also painting the truck yourself, it looks great?
I did contact the Por15 manufacture and they recommended sanding a small area and applying a thin layer of the Top Cote. They did not seem sure if it would work but I will give it a try.

Thanks rc yes, my truck's a rolling advert for POR products! lol.

The reason I mentioned the mask was I learned the hard way,although I was just brush painting it I felt like cr*p the next day.
The satin black's a rattle can 20' job but it'll do just now.

You obviously just looked at the garage pics when it was tidy! lol.

I'm surprised about the manufacturers uncertainty,I would have expected them to be more sure of their product abilities...

Good luck and let us know how things turn out.

They did not offer much help in my situation. I told them about the brush marks and they said that the Top Cote should layout as well as the Por15. They said to sand a small area and "Try", to add a thin coat of the Top Coat and see what happens. No very reassuring. They asked if it was very humid but in my case in N.Calif it was not. I probably not be able to do a test patch until this weekend.