I've welded my flares on. What to do on the backside?

[rennch]

Hi all...

I have my rear RSR flares welded on now, but am unsure how to finish the backside of them. obviously I want to keep the moisture away from the seam. Is there a seam sealer I should use? Por 15 perhaps? undercoating?

Thanks!

[Zeke]

The welded metal will indeed rust very quickly and aggressively. The backside needs to be treated much the same as the front, or topside. This means a thorough cleaning followed by protection. POR should work well if worked into the welds completely. You could follow with underseal or SKS stone guard. The race cars I've looked at have just had the welds dressed, cleaned and painted with the same paint used everywhere else on the car.

[unclebilly]

This was not done on my car BUT if I had done it (and still might) I would have ground the underside smooth and put a layer of fiberglass over the seam.

[rfuerst911sc]

On my 914 I ground the welds flush and then metal prepped with Ospho. After that was dry I used automotive seam sealer purchased from NAPA and I spread the seam sealer over the welded seam. The stuff I used came in a caulk tube so I layed a heavy bead and then took rubber gloved fingers and spread/pushed/smeared it into a flat covering. I let that dry for a week and then brushed on a oil based general purpose primer. I will top it off with a thin coat of auto undercoating and then will top coat with single stage auto paint to match the rest of the car. That should do the trick.