cold galvanizing vs. weld through primer
 

Can cold galvanizing be used instead of a weld through primer when, for example, welding in a suspension pan. If so should it be applied before or after the welding, or both? Thanks

No expert on the subject...but I'd assume that the suspension pan should be welded into place in a unibody in order to maintain unibody cohesion.
That would mean removing any bondo/primer/paint material localy and electrically heat-bonding steel to steel.

Yes, but the problem when you do that is that you leave bare steel, and you can never coat it.

I would be interested in hearing Damons opinion and technique.

FWIW, I used a "weld thru" product in my parts replacement.

wurth aluma-zinc is both a cold galvanize and weld thru primer. i use it a lot.

I was only asking this because I can not find a place locally that has a weld through primer but I have found the cold galvanizing stuff. I need something that works well because I had to make some replacement sections that will overlap with the old metal, hence leaving places that I can't get to after welding. I guess i'll go with john walker and get the wurth primer. hope it's wurth it...ha ha ha. sorry i couldn't resist

Also, John, what do you use to prep the surface. Would the por-15 marine clean and metal ready be good before primer? Thanks.

John where do you get this stuff from, I see some other wurth products on pelican but not the aluma-zinc. thanks

Have you tried a local welding supplies shop?


David Duffield

Thanks for the tip John. Goes into my list of products.

BBJohn,

I believe Pelican can get most any Wurth product if you call. If not Wurth's NE distribution headquarters is located at:

WURTH USA Inc.
Distribution Center Northeast
93 Grant Street, Ramsey, NJ 07446

Phone: +1 (201) 825 2710 ext.2255
Fax: +1 (877) 871 7787
www.wurthusa.com

OR

www.CarCareonline.com may have it in Lodi, NJ.

I am a welding instructor and can honestly say I have never seen this weld thru product at a welding supply store or on any shelf. However if john says its there it must be. ANyhow It does not sound like a good idea to be welding thru galvinzed paint or zinc (any body see erin brokivach or how ever you spell it) One of the best products you can get when finished making a weld with an over lap is called. Corrosion X. It is a mil spec wicking formula used in avaition for stopping the development of of rust. It has a capilary effect. This stuff is much safer to work with. however if John uses that other stuff with success I would listen to him That man deals with way more cars than I. Just my thoughts. Good luck

Ben

thanks rick, never knew that their was a place in ramsey, that's like ten minutes from my house. I guess I'll pick some up today. thanks.

I tried the wurth weld through zinc primer and had trouble getting enough heat with my small MIG. I ended up applying it to the weld joints immediately after the weld was cleaned up, and hopefully before much moisture from the air was able to begin the oxidation process. I followed with two coats of POR-15 and then undercoated the bottom side, and painted the top side.

Looks good, and I feel good about it.

It's at least as good as the factory did on the early cars, and probably a lot better in some cases. My '71 didn't seem to have any corrosion prevention inside the front or rear longitudinals or rocker panels.

I changed that !

Rick

I just got back from the wurth warehouse. Got a can of alu-zinc. Sure is nice to have a wurth warehouse down the block. I am planing on preparing the sections of the metal that will overlap when welded by using the por-15 kit. Then I will spray on the alu-zinc, then do the actual welding. After everything is welded I will prep everything else with the por-15 kit and then paint it with por-15. Finally I will undercoat everything. Is this the right way to do it? This is the first time I've done body work and I really want it to last. thanks.

Sheeesh, that was quick.

.....so you're not coating w/ Por 15 first and then w/ alu-zinc....kinda sounds like that.

the areas that are going to be welded will be prepped with por-15 products such as marine clean and metal ready. then the alu- zinc will be applied and the part will be fitted and welded. all parts out in the open not being welded will be prepped (marine clean, metal ready) and the painted with por-15. sorry for the confusion, I think it came from the fact that the company name is por-15 and one of their products is also called por-15.

anytime you weld thru zinc, it's not going to be as nice a weld as if it were clean, but that's the trade-off. a respirator would be good.

BBJ, Sounds like a good plan.


...and yes welding and zinc = toxic fumes.

thanks guys, i'll be sure to weld out side and wear a respirator. hopefully I'll be doing the welding next week if I can get the floor panel fitted. the suspension pan is almost ready to weld but I am waiting for some stuff from por-15. I'll try to log my progress on this thread with pics.

to see some of the metal patch work I had to do for the suspension pan area you can go here.

http://forums.pelicanparts.com/porsche-912-technical-forum/176853-what-do-about-rust.html

Most respirators are good for organic chemicals used in paint. It would be rare that you would have one suitable for heavy metals such as zinc in your shop drawer. Just remember that the less you inhale the less problems you'll have - good ventilation is the key!

I do like the weld-through primer concept though.

Jim

BB John,
The wurth rep's come by and set up the body shops and then only stop by once in a while and ship most of the items. If there is a body shop near by ask them for the number of the local rep. Or buy a can from the shop. Some will be willing to sell you some. Might as well pick up seam sealer too.

Harold

Here are some updates on the new floor panel.
It to me about 2 days to get the old floor out (what was left of it). Today I started to fit the new floor as well as make some new peices where the metal has rusted away completely.