View Full Version : Por-15 over sand blasted metal?

04-11-2009, 06:14 PM
I have just finished sand blasting my truck's bed.
I would like to paint the bottom of the floor with Por-15.
Which I have not used yet.
The can says "Rusted seasoned, and sand blasted metals are excellent
surfaces to paint on."
However I read a post by "Mr. Biggs" where he states that he painted clean metal and it flaked off.

Has anyone painted sand blasted metal with Por-15 succesfully?
Unless I hear affirmative I am going with etching primer as I want to protect the metal as soon as possible.
The previous owner blasted it twenty years ago and never primed it.
Surprisingly it now looks good.



Allan Songer
04-11-2009, 06:25 PM
As long as you prep the clean metal as per the POR-15 instructions using POR-15 products you should have no problem. Are you going to spray it? If so, make sure you use proper protection, as this stuff is NASTY NASTY NASTY!

Henry Votel
04-11-2009, 06:31 PM
Hi Paul,

Getting a primer coat on the metal it as soon as possible is the key to success on sand blasted metal.

If your bed has been sitting a few days it would be a good idea to wash it with a phosphoric acid based rust converter (POR has Metal Prep, Eastwood has one and your local PPG or Paint supply has them too). Then spray it with an epoxy based primer. This will protect your metal adequately. Follow with your steps for body filler and paint.

POR is hard to finish nicely as a base for primer or paint, unless sprayed; and you really do not want to spray it. There is only a "few hours" window of time that you can cover the POR with your paint in order to obtain good adhesion. After 24 hours the POR has cured and getting good adhesion on POR with primer or paint then requires roughing the surface and that is hard because the POR is tough stuff. POR is used in mostly out of view areas.

Good Luck,

Henry Votel,
Forest Lake, MN
Moderator: Editors & Publishers Forum

04-11-2009, 07:11 PM
Do you mean the bottom of the bed that is by the frame? Or the top of the bottom of the bed that is exposed to sunlight? POR instructs to not use on parts exposed to direct sunlight.

04-11-2009, 08:59 PM
Don't worry about anything. Freshly sandblasted , or even if it's sat a week or two (unless it's been rained on). The only thing you need to do is wear vinyl gloves.. long sleeves and long pants.

NO metal-ready, NO ospho. No phospatizers..

POR-15 does NOT stick to: paint (old/new), bright metal, fine-sanded metal, GRINDER-stripped metal.

POR-15 sticks GREAT to: Rusty metal cleaned with a wire wheel of all LOOSE rust and scale, Sandblasted metal,


Specializing in Studebaker Restoration

04-11-2009, 10:01 PM
I've had good luck with it on clean, blasted suspension parts. As the guys have mentioned, it's not good for parts exposed to sunlight. I painted my tractor seat and even tho it's protected, it's all dull looking after a couple of years.
I use an oil and grease remover to clean the parts first, BTW
Yakima Wa

04-12-2009, 08:54 AM
I know people that use it on clean metal, but the stuff was made from what I know to cover a rusty surface. Of course you do want to knock off the loose rust. Remember the old adds said, converts/neutralizes rust.

Orlando FLA