OK so i'm doing rust damage right now. I have a few small holes behind my seat and one in the corner that I need to fix. None of these are load bearing or even someplace that will get any wear. I will neutralize the rust with eastwoods nuetralizer. That will kill the rust. Now what should I use to fill the holes? They are about 2 square inches. The whole problem of course is that i cant weld and I really don't want to learn on such thin metal.

My understanding is that bondo absorbs moisture unless it is thouroghly sealed. On two of the holes I will not be able to get to the underside of the patch to seal it up. I'm leaning twords fiberglass, but will this stick to the metal?

Any one got any ideas for me.

Thanks

PS mods I put this in here because its on my S5 vert so its a FC related post :p

 

just make sure you scuff up the metal well and have no paint where you want the fiberglass to stick and it will stick and last a long time

 

Fiberglass looks good for a year then starts to separate.

The best bet is to weld it, but if you can't do that then I recommend the trunk pan and floor patch kit from POR-15. http://www.por15.com/s.nl/it.A/id.1481/.f

I have not used it but I have always been happy with their other products.

 

Best way to replace rusted panels if you can't weld is to go to a body shop or a sheet metal place and open your wallet I agree with Aaron Cake, fiberglass won't do it, and this is coming from someone with alot of fiberglass experience. The epoxy can't penetrate the metal so you'll only get a mechanical bond.

 

Ive had good luck with fiberglass for floor boards. I just put the patch on the inside and coat the hell out of the underside with POR-15. Then Ive actually scuffed up and put truck bedliner all over the area after the POR to seal it up.

But yes it is a purly mechanical bond so you need to rough it up down to bare metal near the hole and let the fiberglass bond not only with the metal but the surrounding scuffed up paint also. I actually also use mesh screen (stainless or aluminum) to allow the resin something to bond into (kindal like rebar in concrete).

 

How about you check around for a local RX7/Miata/Mazda/SCCA club. You might find some people that would be willing to help you out with welding for alternative (beer) fuel.

--m

 

I'd be one of those guys, but I'm in CT. I will help for beer though, good beer...

 

Thanks for the info guys. I thought that the fiberglass might have adheasion problems. I'm going to have a shop check on if for me because this is just the first step for me. the drivers side has a large 4x6ish hole in the floorbehind the seat, and then ive got rust along the points where the floor meets the frame. So I guess I'm going to have to use cash. Luckily it is just in the floors, and the frames look good.

Any more ideas would be appreciated.

 

I had a hole on the passenger side of my vert right by the tranny hump(about a 3"x3" hole). I used a cut off wheel to cut out all of the rusted area and made a nice aluminum patch. I then used a drill to put holes into the patch and the floor and held them tight with small nuts/bolts. After the fact, I used seam sealer to coat the inside and the underneath, let it dry then used por 15 to cover the underneath over the seam sealer.

 

If you have enough rust where the floor meets the frame, you'll definitely want to get that kind of damage repaired properly. You don't want to fall through the floor one day because you tried to patch major rust with fiberglass!

 

I have a hole the size of a penny where the dead pedal goes. I was gonna scuff it up and put some rust killer on it adn seal it with silicone. I figured that woud be suffiecient.

 

metal and fiberglass sucks!!!

another solution is go to an automotive paint store and buy some bonding agent. Is like a caulk but is a strong glue. Explain to the guy at the store what is your problem and he will give you the appropiated bonding agent. That glue is super strong and no need to apply rivets to the sheet metal that you will glue. You onle take a sheet metal of the proper size. Drill some holes around and the apply the glue to the floor, then place the drilled sheet metal over the rusty spot and remove the excess of glue. Wait until it dries and paint it. Also I recomend you to clean the underside of the car were the rust hole is and remove all the excess rust, apply some rust neutralize, paint it and apply ruberized undercoating.

Also the POR-15 is a great rust encapsulator. The result that the guy that used it are great. Even that paint is so hard that you will need to make a lot of work to get sanded. I will used my next time into my Porsche 911 underside of the car and behing the carpet.

If your RX7 have that heavy coating like some fendix or someting like that under the carpet, that stuff attracts moisture and began to rust your floor. In my Turbo II I have it superficial rust before I removed it with a chisel, a flat screw driver and a hammer. Then I brushed away with a wire wheel all the rust. I applied rust neutralizer, primer and then paint.

 

That sounds like somthing I might do. Cut out the rust area plus a little. Then find a piece of metal for a patch. Drill holes and rivet the patch in. Maybe clean the area where the patch will mate real good, then prime it with a can of prime. Sandwich some RTV b/t the patch and the floor, then rivetl

 

[/QUOTE]

If your RX7 have that heavy coating like some fendix or someting like that under the carpet, that stuff attracts moisture and began to rust your floor. In my Turbo II I have it superficial rust before I removed it with a chisel, a flat screw driver and a hammer. Then I brushed away with a wire wheel all the rust. I applied rust neutralizer, primer and then paint.[/QUOTE]

actually the holes stayed away fromthe rubberized coating. For the most part anything that was coated is still solid, but right next to it the rust ate through.


I've decided that for the small ones by the pass seat im going to just use a patch. I was going to cut a piece of steal (maybe aluminum) and rivit it down, then use the seam sealer. I'm going to look into "bonding agent" because that sounds like a great idea. thanks.

I may be able to use these methods for all but the ones running down the frame on the pass side. but at least it will save me money only to have one job to pay a pro for.

 

I've decided that for the small ones by the pass seat im going to just use a patch. I was going to cut a piece of steal (maybe aluminum) and rivit it down, then use the seam sealer. I'm going to look into "bonding agent" because that sounds like a great idea. thanks.
QUOTE]

check at Eastwood that people have different bonding agent in their catalog, also I think that they have photos that you can look and take an idea of what to do.

 

I've been using eastwoods rust nuetralizer. Hadn't thought about them for a bonding agent.
After looking at all of my problems today. No patching just some cleaning and such. It looks like i will have to use a bit of everyting.
I'want to do it my self but im going to check money issues first.

I'm going to Andy at Mazdatech tomorow, and see if he does' that kind of work, or can recomend someone.

I'm also going to get an estimate on pulling the engine/tranny/rearend. Basically just see how much it woiuld cost to pull all the turbo parts out of this vert and put it into my N/A vert. I would rather do this myself as well, but i just don't see it happening in my gravle driveway, with Seattle's unpredictable weather.

Plan A is still to try and patch most of the rust myself.

 

Cut some panels the same size as your rust holes then drive for 2 hours to visit me and I'll weld them in for you.

 

No passport. Thanks for the offer though......