I've got a rust problem in the front floor board on my 88 Jeep MJ
Comanche.....no surprise.

I recently repaired a few holes, and I thought I'd post some pictures.

Before anyone jumps on this repair remember.
It's a work truck, not a show truck.






I used materials that I had on hand.
The 24 ga. galvanized sheet metal I had from long ago.
The 1/8" stainless pop rivets I bought a few years ago...hardware close out and I got 400 of various lengths for $4.
The plastic (asphalt) roof repair I keep on hand for when a shingle gets blown off my house or shop.

The first thing I did was remove all rust from the metal.
I used a air hammer with a flat chisel and a round pointed chisel , wire brush and vacuum cleaner to remove all of the scale...the holes got bigger when I did this, but I got all of the rust out.
Next, I used a metal brush on a 4" grinder to make sure that all of the rust was gone.
Next, I sprayed the work area with "Rust Converter".

I then made a pattern of the patches from cardboard, cut them out and marked and cut the sheet metal to fit with hand snips.
I drilled 5/32" clearance holes thru the patch metal in places that I knew the rivets could get a good "bite".
This makes it much easier when drilling the 1/8" holes for the rivets, use them as pilot holes

Next I smeared on a thick layer of roof repair adhesive, enough to fill any contours in the floor metal.

I placed the patches in place and working from the center of the patches, I drilled 1/8" diameter holes thru the floor board and riveted the patches down, working side to side towards each end.
This kept the patches laying flat.
I used a hammer handle to press down on the patch as I set the rivets. This made sure I had good contact and eliminated any voids in the adhesive.

I used a little paint thinner and a rag to wipe off any excess adhesive around the edges....this sealed the edges of the patch very well.
The plastic roof adhesive will harden as it dries and form a firm foundation for the patches.

I then went under the truck, wire brushed the underside of the patch area, cleaned it with paint thinner, applied Rust Converter and then brushed on a thick coat of the roof adhesive, being sure to seal around the patches at the rust holes.

I believe it will last, as long as me anyway at least.

 

Looks like you did as good a job or better than a lot of folks. I did the same but not near as neat except I used seam sealer instead of roof sealant.

 

Good job on that !! I usually use the "Blackjack" roofing caulk gun type, which even smells like undercoating.
You could apply some spray can undercoating on the bottom side of your patches to seal the edges etc.

 

Yea, that "Plastic roof repair adhesive" is actually only asphalt,
the same thing that you're using.
I don't know where the "plastic" comes from in the description, but that's what it's called on the can.
I usually just call it "pitch", but wanted to be correct for the forum.