How clean is clean for Por15?

[Jeff T.]

Hello all,

I started cutting out bad floor repair I did on my hardtop nearly 20 years ago to use a Classic floor that has a bit of surface rust. If I want to use por-15 to seal everything up, how clean do I need to get that floor panel? I know I need to grind where I will weld clean but how about everything else, I plan to run my big grinder with wire brush attachment over the panel to clean off some of the surface rust.

while I am at it, I have a few large pieces of 18 gauge steel around, did Studebaker use 18 or 16 gauge for the floors?

As far as my hardtop, I need to get the right door off and finish cutting and trimming before I can start patching and welding.

Jeff T.

"I'm getting nowhere as fast as I can"
The Replacements.

[rockne10]

From my experience POR15 doesn't stick well to clean steel.

[sweetolbob]

Jeff

I totally agree with Rockne10. My experience with POR-15 on bare steel resulted in it coming off in sheets a year or two down the road. I'd epoxy prime and paint or just use a good rust control primer and paint.

18 gauge is perfect. That's what I used on the 54K and it appeared to be equal or thicker than to original. You will need to run a bead or two or add a couple of stiffeners to stop oil canning.

Good Luck.

Bob



,

[tluz]

POR-15 contains a rust-conversion chemical that bonds with ferrous rust and converts it into an inert substance. If there's no rust, it won't work properly. It doesn't penetrate very deeply, though, so surface rust is optimal, while rust-through is not.

[Jeff_H]

The other thing with POR15 is the surface must be clean from grease, or wax. There is a special cleaning concentrate they sell that is basically some heavy duty caustic degreaser. You mix with water and scrub brush the surface (wear rubber gloves) and then dry. Use compressed air to get water out of any crannies. Sometimes it also helps to use some phosphoric acid etch if the surface is too smooth.

Jeff in ND

'53 Champion Hardtop