TheSamba.com :: View topic

Tue Mar 18, 2014 4:37 pm

Just welded in new rear pans in my body off resto.
I will be doing the top and bottom of the chassis with the POR15 and want to know the best way to do it......
I bought the whole POR 15 kit with the degreaser, acid etcher, and the POR 15.

Is it okay to spray some etching primer or primer over my new welds so that I can keep the rust off of it until I get a chance to do the whole top/bottom of the chassis? I'm concerned that if I don't get to it in a week it WILL rust and might be a pita to get it back off again!
OR
Do I just leave it and use the degreaser, etcher, and then the POR15?
OR
Do I sandblast a section at a time, then wash with degreaser, then etcher, then POR15?

It seems like an awful lot of stuff to do in one day!!
Sandblast the whole chassis, spray degreaser on the frame, spray the etcher on the frame, THEN paint the frame with the POR15!
And finally, when you spray the frame with the degreaser on the frame and then wash it off, won't water still be stuck in little nooks and krannies? How do you get all of those little areas dry or when you spray the etcher does it absorb or "dry" that area to prep it for the POR15?
Lots of questions I know-just wanna do it right!! Thanks, in advance, to anyone who can help me out!!

Tue Mar 18, 2014 6:06 pm

If you’re concerned about rust forming in 1 week and being a PITA to get off, it won’t be. It’s just surface rust and can be knocked off with a wire wheel. It’s also designed to go over clean or rusted surfaces so just follow the directions. Use an air compressor and an air chuck to blow water off if you need to. Also, be careful that you don’t apply it if there’s high humidity or else it will bubble. They claim it cures faster with moisture, but if you spend more time reading their info sheets it will tell you not to. I had no problems with it one time and then the last time it bubbled up like crazy. It was a humid day and I thought it would be fine as per their claims. It wasn’t until the bubbles formed that I dug further and called to find out that moisture makes it cure faster, but with that comes bubbles. I’ll never use it again. I sanded it down and finished my pans with Rustoleum Rusty Metal Primer and then a Black Rustoleum Satin Paint. 2 coats of each and no POR 15 prep BS.
Best of luck!!!

POR 15 on a humid day. It cured fast though...

Tue Mar 18, 2014 6:37 pm

So I just paint over the "surface rust"? It's being stored outside of a friends garage because all of his bays are full (has 4 bays)
I cover it with a tarp every night and try to make sure as little rain/etc gets into it. Wonder if I should sandblast the rear pans, then do the degreaser, then the etcher, then the por15. Once that has cured, go back and do the FRONT pans with the degreaser, etcher, then the por15, etc.......
Then, once I get the whole floor done go back and do the whole floor again with a second coat of it all.
Just need some direction here. Thanks

Tue Mar 18, 2014 7:39 pm

I would not worry about a week or two without paint but if you want spray the acid on the raw metal. That can keep it rust free for quite some time

Tue Mar 18, 2014 8:03 pm

I would get all the repairs finished first. Once you’re done with that make sure there’s no flaky rust or loose paint, etc. Then, when you have a few hours seal up one side. If you want hit it with a wire wheel to clean up any surface rust. Degrease with Marine Clean as per their directions and then use the Prep and Ready stuff. That will convert any rust and leave a coating of zinc phosphate which will help bond the POR 15. As djway3474 mentioned, it will also protect the metal for some time if you can’t get to the next step right away. Don’t just paint over the surface rust without doing those steps. That’s pretty much it unless you run into other problems like I did. Then flip the pan over and repeat on other side.
Use air and a heat gun to help speed up the process of drying the water before applying the POR 15...

Wed Mar 19, 2014 7:34 am

I was hoping I could spray a very light coat of primer over it to keep the surface rust off, then when I spray the "etcher" it would just eat it away.

Sounds good! Is there any way to get inside the center tube? I see it's a little wet in there from sitting outside..... There is already a hole cut because the previous owner welded the clutch tube in at one time. I would LOVE to know if there is a way to "fog" inside the area and my heat channels too!
(Like take a sprayer and spray down the tube some would be real nice)
The heater channels are in great shape (Cali bug) and I would like to prolong their condition for as long as I can!
Thanks again!!

Wed Mar 19, 2014 7:52 am

^^ I've never done it (not at that stage yet), but that's something people definitely do. There are a ton of different products like Waxoyl that you heat up, and spray inside parts for rust protection. Or you could try something like this: http://www.eastwood.com/internal-frame-coating-w-spray-nozzle.html

Regarding the POR 15: According to their website its supposed to adhere well to sandblasted metal. You need the acid etcher to give POR something to "bite" to, I imagine sandblasting would also provide such a surface.

But if you're going to the effort of sandblasting, why not just prime right over top? If you POR the frame now, make sure you're never planning on painting it any other color, its pretty horrendously hard to sand/prep for a top coat once its dry.

Wed Mar 19, 2014 8:14 am

http://www.thesamba.com/vw/forum/viewtopic.php?p=3376876

Wed Mar 19, 2014 1:51 pm

Bookmarked!!
Thanks, just what I needed!