Body experts. Advice?

-

moparmandan

FABO Gold Member
FABO Gold Member
Joined
Jun 28, 2017
Messages
2,999
Reaction score
3,007
Location
Deland, FL
What process should I use to prep and preserve this? Before and after re-assembly of the tail section. Thanks!

Clean to bare metal and use weld through primer? Maybe POR 15 on the backsides?
20180630_143118.jpg


Just a test fit. Will disassemble and prep before welding:

20180707_190404.jpg
 
Clean to bare metal and use weld through primer anywhere you need to be spot welding. I wouldn’t POR15 anything until the welding was done or I was at least a few inches away from where I was going to be welding, that stuff welds like crap.
 
Clean to bare metal and use weld through primer anywhere you need to be spot welding. I wouldn’t POR15 anything until the welding was done or I was at least a few inches away from where I was going to be welding, that stuff welds like crap.
Also remember that POR-15 is designed to go over cleaned rusted metal. It is not designed to go over sand blasted metal. To clean up bare metal in your
welding areas I use the 3M black paint buster discs. They are 4" in dia. with a hole and use a metal arbor. They also make a rolok style, but I hate those as
they always break. These 3M discs are pricey but they work very well. If you use the paint buster discs wear eye protection. They can throw some sparks and
the material from the disc can go flying as well.
 
I have had good luck with RustMort. It is a phosphoric acid solution that converts red oxide (rust) to a black oxide coating. Wipe it down after treatment (follow directions on product) and prime over it. Rust Mort™ | morttm | SEM Products
 
I wouldn't use POR-15 on anything. POR=Peels off Regularly
It's hard to beat Epoxy primer, after you have finished your body work. Its not that much difference in price either.
Dave
 
Clean to bare metal and use weld through primer anywhere you need to be spot welding. I wouldn’t POR15 anything until the welding was done or I was at least a few inches away from where I was going to be welding, that stuff welds like crap.
Great advice. Thanks!
 
Also remember that POR-15 is designed to go over cleaned rusted metal. It is not designed to go over sand blasted metal. To clean up bare metal in your
welding areas I use the 3M black paint buster discs. They are 4" in dia. with a hole and use a metal arbor. They also make a rolok style, but I hate those as
they always break. These 3M discs are pricey but they work very well. If you use the paint buster discs wear eye protection. They can throw some sparks and
the material from the disc can go flying as well.
Thanks, I searched those disc's, they are nice!
 
I'm not a hater of the 74 up rears, but since the po was already headed in that direction, I'm going with the momentum. All the parts except the quarter caps came with the car. I won't mind losing the 500 lbs of bumper and shock absorbers.
 
If I use RustMort, it's after welding I assume? Thanks for the help!

I would use RustMort before welding. It is really hard to clean up all areas before welding to bright shiny metal. After the metal is prepped, go ahead and use weld through primer where you ar going to weld epoxy primer everywhere else. Here is a picture of my 71 Barracuda floor board that had quite a bit of surface rust that was prepped with RustMort. After wiping it down to remove the residue, it was ready to prime over.

IMG_1902.JPG
 
I would use RustMort before welding. It is really hard to clean up all areas before welding to bright shiny metal. After the metal is prepped, go ahead and use weld through primer where you ar going to weld epoxy primer everywhere else. Here is a picture of my 71 Barracuda floor board that had quite a bit of surface rust that was prepped with RustMort. After wiping it down to remove the residue, it was ready to prime over.

View attachment 1715200923

Just remember that if you use RustMort or a similar conversion treatment before welding you'll still have to clean the areas you want to weld on back down to bare metal. The oxide it creates doesn't really weld any better than the rust does. Nothing wrong with doing that before you weld, but the places getting spot welds still have to be bare metal and not oxide.
 
I don’t use POR at all on body panels! Areas that are rusted really need to be media blasted and cleaned and then use a weld through primer or if no repair is needed then use an Epoxy Primer. Body filler can be used on top of Epoxy...the only thing about Epoxy is...if your not gonna top coat it with paint or 2k primer and it’s over 24hrs since you applied it...you will have to scuff it with a scotchbrite or wet sand it prior to assure proper adhesion.
 
If it's only light surface rust, you can also use DX579 (muratic acid). We use it at work diluted down to 3:1 water:acid, spray it onto a rusty surface and let it sit for a couple minutes, scrub it with scotch-brite, and then wash it all off.
 
Just remember that if you use RustMort or a similar conversion treatment before welding you'll still have to clean the areas you want to weld on back down to bare metal. The oxide it creates doesn't really weld any better than the rust does. Nothing wrong with doing that before you weld, but the places getting spot welds still have to be bare metal and not oxide.
OK. I was wondering about that. Thanks.
 
-
Back
Top