This past weekend i started cleaning my car up, and in the next few weeks i should be getting my hands on a sandblaster to get rid of all the rust on the car.

Problem is, since this is my first time tackling something like this, i'm not sure what the best undercoating to do is.

I was thinking i could just strip everything and put a nice coat of por-15 down, then paint over it.

Or i was thinking put por-15 down over the areas where there is rust, and just primer/paint over the areas that have no rust( if they didn't rust after 15 years they should be fine..).

or i could just priver/paint everything. Problem is i'm not sure what exactly the best way going about this is.

Also what would you do for the interior floor pans. Mine aren't too bad, but their are some areas that do have surface rust. Should i just primer/paint or por 15 them or what.

We also thought about primer and lay down some truck bed liner over the bottom of the whole car.

But what would you guys do?

Heres some pics so you can see the exact shape the cars in:

 

I think por-15 is probably one of the best ways to go. I am sure all the methods you described have been tried here, but you cant go wrong with por-15

 

Crikey! That's the first time I've ever seen anyone make their own frame lift. Good job! I'd POR-15 the entire underside just because it forms a non-permeable skin that will help repel any future rust-forming moisture. It has lasted this long, but since it's so easy to do the whole thing right now, I'd just get it all out of the way.

 

Isnt the whole point of POR15 painting it on to Rust to get the best results? I would think if your at that point your going to blast it to bare metal and do it right... just my 2cents though.

 

since you have the whole thing apart, I would have the whole thing brought to a bodt shop on a flat bed and have them paint the whole thing inside and out. It will look beautiful when it's done!

 

POR-15 adheres to non-flakey rust a bit better than bare clean metal. It should adhere anyway, but I've never laid a coat on clean metal before. There may be a special priming procedure in that case.

 

Wish i could take credit for the frame lift, but my dad and his friend did that one weekend when i wasn't there.

I plan on painting the car black, among other things are possible too, but base is black.

So i plan on painting the underside and interior with a gloss black, nothing special, but it will look good. All the parts i bolt to onto it will also be painted. After i get the underside completely done, i'll get the rear on it and then from their do the engine bay.

Then the drive train, then have it towwedto my painter(Someone that does paint on the side, not a shop.)




POR-15's Metal Ready is what i'd have to use to prepare the surface of the bare metal. The same stuff you put on the rust to neutralize it.

What would you guys do to the metal on the interior. I was thinking maybe just POR-15 the floor pans and firewall.

And last for right now, could anyone give me an estimate on how much POR-15 i would need to order. I only get to work on the car about 1-2 weekends a month and when i order the stuff up, i would like to get everything i need in one shot. Better to have a little extra, then not enough.

Thank you!

 

I don't know how many gallons you'd need.

Also, make certain you use a quality paint for any basecoat as a bad paint will cost more in the end to remove before a full paint job (doesn't matter much for the underbody, obviously).

 

What I have done to the underside of my car, because here in Canada a non undercoated car doesn't seem to last long. I have simply removed the paint and rust so I am down to bare metal. From there I applied a metal treatment full of different acids. From there, once it is dry I applied tremclad rust paint (flat black so undercoating sticks better to it) and spray on undercoating on top of that. I haven't put this vehical on the road since doing this, Im in the middle of major body work. However, my much older buddy did basically the same thing on his 69 mustang many years ago. Probably in the mid 70s and it held up well. His friend who did not undercoat his mustang, had it rust a few years later. It sat in a garage for 20 some years and they are now redoing the entire car.

PS. If you are thinking about it, you should either buy or make subframe connectors and install them ASAP. Then when you spray undercoating or paint or whatever, it doesn't get burned off later if you are welding on the car. Just make sure the body isn't twisted when you do this.

 

I'm gonna be buying Spohns subframe connectors before i do the undercoating.

So i guess as of now, my plans are to completly strip the whole underbody and coat it all with POR-15. I'll probably also do the floor pans, firewall, and a few other areas that may rust on the interior side.

I'm hoping i can get away with 2 gallons(8 Quarts would probably be worth the little extra money?) of POR-15 and one gallon of Metal Ready for everything. Hopeing to get 2 coats out of it?

Thanks to all the advice and comments so far. This site has helped me learn sooooo much as it is. I'd never think of going with an LS1 if it wasn't for the boards.

 

I am in the middle of coating my underbody...except I'm using Zero-Rust. First, I hit what I could with a wire wheel on a hand grinder, then sandblasted the rusty parts I didn't get with the grinder and sprayed the leftover rust with acid. Then brushed and sprayed on the Zero-Rust. Good thing about Zero-Rust is that they sell spray cans for the spots I can't get with a brush.

Oh yea, I have used 1/4 of a gallon painting 2/3 of the underbody. Two coats.

 

I wouldn't use POR-15. I'd use something more like Rhino-liner roll on truck liner. I would think it would hold up better, not too mention add some sound dampening.

I used to be a big fan of POR15 but it has a tendency to not stick sometimes, regardless of how well you prep it. Then it peals off in sheets. I was not real impressed with the stuff after 4 -5 years of being on the car.

 

I go along with Jimp2001. Take it in and have the entire frame chemical dipped and then painted. After all the work you put into rebuilding it, I doubt you will ever drive it in snow or rain.