Welder Can't Weld STAINLESS?

klaucke · 03-24-2006, 08:53 AM

Guy's I'm trying to weld some stainless steel w/ my Hobart MIG welder. I have stainless wire, but normal mild steel gas that is 75% Argon/ 25% CO2. It just won't weld. It will strike an arc at first but then die, and a "glob" forms on the wire.

I used this same set up this past summer and it worked great, but I was just tacking nuts onto bar stock. Now I have to run some short beads.

Any ideas? I had the stainless wire out of the machine for a couple months, could oxide have formed on the stainless wire and that is what is screwing me up?

As far as I know, it was working fine with the mild steel wire, but I'm about to go put that wire back in and try it again.

Any input is appreciated!

BlueSkyJaunte · 03-24-2006, 09:24 AM

http://www.lincolnelectric.com/knowledge/articles/content/migweldss.asp

sammyg2 · 03-24-2006, 11:25 AM

What kind of stainless steel base metal? 308, 309, 316, 410, 416, 420, duplex, etc. Is it at least magnetic?
I have books full of engineered welding procedures in my office that detail base and filler metal, gasses, pre-heat, interpass temperature, stress relieving, if you can ID the base metal I will pull up the procedure.

RickM · RickM's Garage

Sammy, Are you in the Pipe hydroforming business?
(sorry for the hijack)

lendaddy · 03-24-2006, 11:40 AM

Quote:

Originally posted by RickM
Sammy, Are you in the Pipe hydroforming business?
(sorry for the hijack)

"Tube-hydroforming", Pipe is for plumbers

Sounds to me like you have a welder issue. Welding stainless is not very different when using MIG. Not so much that you go from laying bead to just globbing the wire. Make sure your gun is grounded well, it could be a loose connection.

sammyg2 · 03-24-2006, 01:26 PM

Nopers, I run a shop that repairs high end centrifugal pumps. we do just over $7 mil a year in repairs with 18 men on the shop floor. Keeps us running.

We are constantly welding on exotic metal parts to repair erosion and corrosion and general wear. When an impeller costs more than a nice 911 SC and takes 16 weeks to replace, it makes sense to weld it up and machine it

Anton · 03-24-2006, 03:50 PM

Check your grounds. Then re-check your grounds.

Clean your workpiece.

Also, are you SURE both the wire and metal are stainless?

klaucke · 03-24-2006, 05:39 PM

Guys I'm trying to weld a non-magnetic stainless, actually it is a keg that I am making a grill out of. I made some hinges from stainless and I am trying to weld them on. The hinges are made of the same bar stock I welded before, which last year the same set up worked great on. I have also tried to weld on just some plain stainless stock (not the keg) and it won't weld properly.

Everything is very clean, I hit it with the grinder to get to clean, fresh metal. I ground a spot to hook the ground on the welder up to as well. It is definately a welder issue and not a work piece issue. I'll look into it more tomorrow.

The cable from the machine to the cord for the gun is connected and in good condition, but I did have to switch tips for the .030" wire. Maybe this is where the issue is? I'll clean everything tomorrow to see if that makes a difference.

billyboy · 03-25-2006, 09:41 PM

try argon

dean · 03-26-2006, 04:23 AM

Play around with your voltage and wire speeds. It sounds like you have too much voltage or not enough wire speed.

Tim Hancock · 03-26-2006, 06:53 AM

Quote:

Originally posted by dean
Play around with your voltage and wire speeds. It sounds like you have too much voltage or not enough wire speed.

Was thinking kind of the same. If the wire is melting back to a blob at the tip, it sounds like the wire is either not feeding or feeding too slowly for your heat setting. If you haven't already, check to see that your wire is indeed feeding properly.