TheSamba.com :: View topic - Can I put epoxy seam sealer over POR-15?

Wed Jun 12, 2019 11:48 am

Next project up is to do something about my seams. Its not too bad and I plan to just attack from the outside for now, to stem the rust until this winter when I will pull the kitchen.
Here is a pic of the ugliness:

So after doing some research here, I think I will proceed as follows:
1. dig out the old junk in the seam
2. clean up the adjacent areas on either side of the seam with sandblasting, etc.
3. flush with phosphoric acid.
4. rinse and let dry completely
5. Coat all exposed metal with POR-15.
6. Fill the seam with 3M 08115 Panel Bonding Adhesive (2 part epoxy)
7. Top coat to match
Here is a link of the product I am thinking of using:
https://www.amazon.ca/3M-08115-Panel-Bonding-Adhes...N1ER0A0S32

so does this sound like a plan?
Is my choice of seam sealer OK.
There is also this stuff that maybe a better choice, I am afraid the one above may sag.
https://www.amazon.ca/Norton-636425-97121-SpeedGri...mp;sr=8-78

I'm worried about using something that may not be compatible with the POR-15.

My choices on epoxy are limited up here in Canada. Kinda stuck with whatever amazon.ca has.

Thanks everyone, your advise and savvy is much appreciated!

Wed Jun 12, 2019 12:10 pm

I'd hit it with the ospho for now and then wait until next year when you can go at it from the inside too. Do the whole job right then.

I am not a fan of Por15 for this area, it is brittle and sometimes does not adhere well...

Wed Jun 12, 2019 12:45 pm

So.... are you suggesting I just put brush on some Ospho and then deal with it after the camping season? Do I do any surface prep or just soak it in there? Any top coat after that?
What would be a better alternative than POR-15 for treating the bare metal before I lay down the epoxy seam sealer when the time comes?
txs

Wed Jun 12, 2019 1:25 pm

Skip the Por-15.
Instead use a good primer and quality paint, or a 2 part epoxy primer and quality paint.
This is not a good application of Por-15, the stuff is better for rough surface, out of sight work. It tends to peel away from smooth surfaces, it's very hard to feather, and other paints don't adhere well to it.
As for the Ospho, it must be over-coated. It is not a paint, just a converter.

Kudos for going after those seams, doing just about anything is better than nothing. Stopping the rust from spreading is job one.
It's sad to see those vans with awful cancer eating away when a little work can slow the decay.

Wed Jun 12, 2019 2:15 pm

x2 with MsTaboo :!:

You don't want POR15 between your steel and your primer. POR15 is for places that you cannot do the proper surface treatment process.

Wed Jun 12, 2019 3:15 pm

To do a "quickie" job to last you until winter, you can just sand down all the surface rust, clean out enough of the old seam sealer as needed to get new seam sealer in there, and repaint the affected panel.

If you are planning on "doing it right" in the winter, then removing the standard seam sealer you apply now will be easy in the winter. When using the 3M epoxy seam sealer, you need to remove all the old seam sealer, primer and paint so that the 3M epoxy seam sealer is applied to bare metal. This is the real secret with the 3M epoxy product - - it sticks to the metal and therefore keeps moisture away from the metal. This is the same principle with epoxy primers - - they do not "wick" moisture to the metal the way that body filler or spot putty or polyester primers can do.

If you have surface rust without holes, hit the surface rust with a narrow-shot sand blaster, sand the blasted metal with 120 grit paper, and it will then be ready for the 3M epoxy seam sealer.

For what it is worth, your rocker panel appears to be in very good condition, especially for rusty Eastern Ontario! In fact, you might be better off just using the van until winter when you can do it right.

The Vanagon factory white base coat is easy to blend in to the original paint, so you can confine your "quickie" repair to just the affected area more easily than on the metallic paints.

Regardless the method you choose, sealing your utility boxes and the fridge vent is critical, even under the screw heads. I use quality dumdum, but 3M windshield sealer is probably even better for this:

3M Auto Bedding and Glazing Compound, 3M part #08509

Wed Jun 12, 2019 8:07 pm

Thank you Howesight, that was helpful.
What 3M seam sealer do you prefer, the one I reference above. There seems to be so many kinds. self leveling, sag, no sag...etc
Also, were you able to purchase this stuff on-line in Canada somewhere?
Txs

Thu Jun 13, 2019 4:26 am

Honestly?
IMHO ...... it has been rusting for 30 years.
Nothing has been done to it.
To spend the Summer still rusting is really nothing when viewed in the in the big picture of time.

Enjoy the Summer, go camping, fix other things that aren't going to be "done properly" in three months time.

A temporary seam fix is lot of work for little if any real return on the time invested.

Dave

Thu Jun 13, 2019 5:49 am

Hey, another white Ontario van :) I'm closer to Toronto.

When I did my repairs, I gutted the van as most of your issues are from inside out, pretty well guaranteed. I agree to leave it for the summer since you only got a few months worth of good weather.

Your van looks in similar condition to mine when I bought it, we got lucky.

What I did:

Yank the interior and take care from the inside out to stop the rust and seal the seams. Por 15 doens't work well with smooth surfaces or an incomplete prep process. I use an ospho or etching solution to get that metal prepped as much as I can.

I find ANY solution will fail if you don't prep properly or skip steps. I've had good success and horrible results with Por, depending on how I paid attention to the details.

I derusted from the inside out, removing all that old insulation, scrape, grind, reseal all those accessory boxes, make sure you aren't getting water from under your window seals. Mine had rusted under a couple of the windows and i had to do repairs there too !.

Prep and paint with, or something similar to, Por 15, I used rust bullet last time around, seems fine, but thick. Prep will kill your work if not done right.

I like the idea of the epoxy primter, i thought it was only available to guys with paint guns who like to mix and spray. It is available in spray cans at NAPA too !

Outside the van, I had mine media blasted. If you don't get the right guy it'll make a decent mess outside of the groove. Then use a pick, scaling tool or some such thing to clear out all that crud in the seams. I then ospho prepped the seams several times, i think it was actually Por Prep, scrubbed it in, rinsed, dried, then rust bullet, then used a seam sealer from NAPA, some Canadian made brand to seal all the goodness in ( after a proper drying time, don't rush it ).

After that, some primer, if you use Por, they do have a Tie Coat primer to adhere to dry Por, use it, and spray canned a few cans of L90D mixed paint from NAPA to seal it all up, some rubbing compound and waxing to try and bland it and hold it all together once it dried properly..

The repairs have held perfectly for several years now, I don't drive it in the winter but it gets its fair share of wet. So, so far so good ...

Good luck, and yes, don't rush it. It is better if you a methodical approach from all the goodies and tips in the seam articles ...

Thu Jun 13, 2019 7:41 am

I like using an Oscillating type tool like FEIN and Everyone else offers to easily remove the Seam Sealer from the Seams.
Use a Fine Tooth Metal Blade in the tool, tape either side of the seam with several layers of masking tape to prevent slips from the blade.
Use a smaller/narrower blade versus a Wide blade if you are needing to work around a tight area, otherwise, a Wide Blade may be easier for you to track in the seam since it will have a wider foot print.

Thu Jun 13, 2019 5:21 pm

My take on a quick fix that is quick and will last until you can do it proper.

1. Knock down any rust bubbles with a wire wheel on angle grinder or putty knife.
2. 3M 35132 Mar-Hyde, 2 coats. This actually chemically converts rust into a solid paintable surface. Slather it into the cracks.
3. Tape area off and paint it.

This will take 30-45 minutes and it'll actually protect it.

Fri Jun 14, 2019 5:24 am

Thanks everyone. Ok, its now a winter project, and I'll only have to see that ugliness for a few more months.
New recipe:
1. dig out rust and old seam sealer inside and out
2. Ospho inside and out
3. rinse
4. apply epoxy primer (most likely Pro form http://www.proformproducts.com/en/products/paint-r...er-sealer/
5. apply seam sealer. This one sounds good but hard to find in Canada Lord Fusor 108B
https://www.lord.com/emea/products-and-solutions/a...8medium%29
6. apply my top coat.

Not sure if the seam sealer should go on first and then prime or go the way I have the process outlined above.

All comments and suggestions most welcome.

Fri Jun 14, 2019 6:24 pm

Prime, then seam seal.

Better yet...... epoxy primer prime.

Primer is designed to stick to metal filling all voids in the surface.

Seam sealer....... well....... it seals the seams closed from water/air infiltration.

Dave

Fri Jun 14, 2019 6:45 pm

jlrftype7 wrote: I like using an Oscillating type tool like FEIN and Everyone else offers to easily remove the Seam Sealer from the Seams.
Use a Fine Tooth Metal Blade in the tool, tape either side of the seam with several layers of masking tape to prevent slips from the blade.
Use a smaller/narrower blade versus a Wide blade if you are needing to work around a tight area, otherwise, a Wide Blade may be easier for you to track in the seam since it will have a wider foot print.

Keep in mind that these seams are created by spot welding metal together.

While I fully support using the Fein, it is what I used, do NOT cut the spot welds!!!!

Dave

Sat Jun 15, 2019 4:48 am

thanks Djkeev. much appreciated

Sat Jun 15, 2019 8:49 am

djkeev wrote: jlrftype7 wrote: I like using an Oscillating type tool like FEIN and Everyone else offers to easily remove the Seam Sealer from the Seams.
Use a Fine Tooth Metal Blade in the tool, tape either side of the seam with several layers of masking tape to prevent slips from the blade.
Use a smaller/narrower blade versus a Wide blade if you are needing to work around a tight area, otherwise, a Wide Blade may be easier for you to track in the seam since it will have a wider foot print.

Keep in mind that these seams are created by spot welding metal together.

While I fully support using the Fein, it is what I used, do NOT cut the spot welds!!!!

Dave

If that tool will cut through spot welds, I know what my next purchase is going to be.

Sat Jun 15, 2019 9:50 am

I use Waxoyl and swear by it. I’m not going to be doing a frame off anytime soon and that stuff is the only thing I’ve seen deliver on it’s claims of stopping and preventing rust.