Hello,

First time posting, now have my 71 in the garage next to my house so I can spend countless hours and $ on it this summer. My first question, my floor pans are rotted gone, I have a lot of 18ga cold rolled sheet steel and will use that instead of buying a pre made pair, and use some 16ga rectangle steel for the floor supports, to save some $.

Is there a hard and fast RULE, should the new pans go over or under?

Cut out the old and weld in the new. Chances are you dont have anything left to weld to anyway.

Welcome to the club.

But if there is,something left good to weld to, should the new go over or under?

If you are leaving the seat supports in you have to go from under If you cut them out you can go over .

I haven't done it that way but I think I would put them under so the old steel would not come into contact with as much water in the future. Asthetically, it would hide the rotted floor and your carpet would cover the bad pans.

I would follow the installation with a good coating of por-15 on the inside. You also could coat the outside of the old pan prior to welding with por to help discourage them from rusting more.

Good luck.

What should one spray the undercarriage with after it's done? I am going to do a similar sheetmetal/tube repair job to my floors. I'm just wondering how to seal the bottom of the car up afterwards - bare metal instantly starts oxidizing after all.

Rustoleum?

por 15, and maybe something over that if it will stick, i used a bunch, wear messy cloths

I agree, POR-15 will prevent it from rusting. It will almost be guaranteed to prevent you from painting too. You will need to scuff it up with a wire wheel I think then hit it with some 600 grit and maybe you will be able to prime or undercoat it prior to paint. Although you probably don't need undercoat with POR-15 unless you are using it for sound deadening.

Read all about POR-15 hear: http://www.por15.com/

John

If strict originality isn't an issue, a good undercoating material to use on top of the POR-15 is 3M Body Schutz. It's a rubbery material that's sprayed on (you can get cheaper guns than what 3M sells), and it can take the heat of being near exhaust pipes. This will cover up any sheet metal/welding "anomalies" you might have and give you some good sound deadening. We're about to put this under the cab of my son's resto-rod truck.

Yeah I wouldn't think you need to paint the underside of the car unless you have a lot of candlelight dinners underneath your car. Most cars I've seen have sort of a fuzzy look of think undercoat material on the underside. Sounds like that 3M stuff is the way to go.

EDIT: That POR-15 stuff sounds like the $^!#!

Edited April 14, 201014 yr by Z-Luke