Seam sealer question. - PeachParts Mercedes-Benz Forum

Clemson88 · #1 12-22-2021, 01:45 PM

Perhaps some advise for those who intend to repair rusty metal with replacement pieces.

I have prepared all the sheet metal replacement pieces by sanding with no finer than 180 grit according to instructions of most 2K primer producers. Joint which lap or have flanges with contact surfaces which will spot weld together have been painted with Transtar 2k epoxy primer before welded into place.

No other areas will be painted until the pieces are in place, the welding on them is complete and surfaces are prepared to prime. I am not grinding welds down on parts which can not be seen.

I drilled a spot weld hole in one of the pieces then used a drill bit which was cut blunt to clean the other part butting to it so welds would be efficient.

I will paint the parts which were not primed before the welding was done and scuff them for a coating of sealer in places which sealer are needed.

For the underside of the body I hope to afford a thick 2K sealer applied with the proper caulk gun and wiped by latex gloved hand dipped in wax and grease remover. I will also use this sealer on the dimple where the rubber drains rest in the trunk wells beside the spare tire well (area of drains and drainage). This thick sealer has to be forced into place. If you don't put it there, it won't be there and you'll trap oxygen and moisture beneath the sealer.

I have at least on place where I'll need to shoot a bit of the self leveling 2K sealer. Shame, 40 bucks to seal a couple spots.

It appears the use of masking tape is critical to have nice seams. Fortunately, none of what I'm sealing at the time is exposed to the eye. I expect a more serious and complicated process when I clean and reseal the ditch drains running down the sides of the roof on this car.

Since I started this thread I thought I'd share my research.

Hogweed · #2 12-24-2021, 12:27 PM

thanks! i have a floor repair coming up and i'm sure i will use that spot welding technique

Quote:

Originally Posted by Clemson88

Perhaps some advise for those who intend to repair rusty metal with replacement pieces.

I have prepared all the sheet metal replacement pieces by sanding with no finer than 180 grit according to instructions of most 2K primer producers. Joint which lap or have flanges with contact surfaces which will spot weld together have been painted with Transtar 2k epoxy primer before welded into place.

No other areas will be painted until the pieces are in place, the welding on them is complete and surfaces are prepared to prime. I am not grinding welds down on parts which can not be seen.

I drilled a spot weld hole in one of the pieces then used a drill bit which was cut blunt to clean the other part butting to it so welds would be efficient.

I will paint the parts which were not primed before the welding was done and scuff them for a coating of sealer in places which sealer are needed.

For the underside of the body I hope to afford a thick 2K sealer applied with the proper caulk gun and wiped by latex gloved hand dipped in wax and grease remover. I will also use this sealer on the dimple where the rubber drains rest in the trunk wells beside the spare tire well (area of drains and drainage). This thick sealer has to be forced into place. If you don't put it there, it won't be there and you'll trap oxygen and moisture beneath the sealer.

I have at least on place where I'll need to shoot a bit of the self leveling 2K sealer. Shame, 40 bucks to seal a couple spots.

It appears the use of masking tape is critical to have nice seams. Fortunately, none of what I'm sealing at the time is exposed to the eye. I expect a more serious and complicated process when I clean and reseal the ditch drains running down the sides of the roof on this car.

Since I started this thread I thought I'd share my research.