TheSamba.com :: View topic - Mig Welding -- Can't clean backside of weld

Fri Aug 15, 2003 4:08 pm

I'm going to be welding some repair pieces on the underside of my bus to both the outriggers and the belly pans. I have cut out the front 1 1/2" of the rusty belly pan and a few areas of the outriggers and the middle support. I can't get to the backside of all the areas I am welding and am wondering if I will have a hard time making good welds. I have mig welded before but in areas where I can access the back of the weld.

Thanks,

Doug

Fri Aug 15, 2003 5:45 pm

If you can spray some weldthru primer on the back and front side of the welds then try and get as much primer as possible on the back sides it should be ok

Fri Aug 15, 2003 6:06 pm

Kosmiride,

Thanks for the info. Never heard of that product. How does it work?

Doug

Fri Aug 15, 2003 6:57 pm

Eastwood sells some weld thru primer that you can use. Also, there is a relatively new product Picklex20 that you can buy directly from the manufacturer. You will find more info on their websites.

www.eastwoodco.com
www.picklex20.com

Felix[/url]

Fri Aug 15, 2003 10:50 pm

OK, weld thru primer does not truly protect against rust. Since weld thru is used just prior to welding, it is actually burned off anywhere near the weld where severe temperatures were achieved. Most modern shops that follow ICAR regulations use a material that coats the inner surfaces of the parts being welded wih a gooey, waxy substance much like cosmoline. Ask for it at your nearest bodyshop supply store. It comes with hoselike attachments for reaching into long rocker channels and even heater tubes. It is a more modern rustproofing material and the name of the before mentioned material as of now slips my mind. Good luck! :)

Sat Aug 16, 2003 7:49 am

YEah I use that ^^^ shit all the time.. #m Pruduct..I you do have to have about a 3/8" access hole.. Use a rbber plug when you are done.