Stainless HELP (newby)

  1. Ram48 Member

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    8
    Hi
    I have a question about Stainless welding with the MiIG
    I need to fix a sink for a buddy and it will most likely be the only time I weld (or try to weld) stainless. Can I use the CO2 / Argon gas I have with the mild steel wire or do I need to use stainless wire and a different gas.
    I am starting to feel like I am in over my head with this project.
    Thanks in advance for your help.
    Ray
     
  2. malcolm

    malcolm Hej!

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    You'll need to get hold of a reel of stainless wire, but the CO2 argon mix will be fine as a shielding gas. You'll just need to clean the surface a little after welding. Don't worry about the actual welding - it's much the same to do as mild steel.
     
  3. Hitch

    Hitch Moderator Staff Member

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    Ideally an Argon/Oxygen mix. With 316ss wire.

    A sink?? Thin..... be carefull!!
     
  4. Hitch

    Hitch Moderator Staff Member

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    But the Argon/Co2 will be ok, but you will get a bit of discolouration.
     
  5. Ram48 Member

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    Thanks guys.
    The sink is a commercial one in a pizza place so it a fairlly heavy gague.
    Thanks again
    Ray
     
  6. Metalúrgico Member

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    the only problem with welding stainless steel with regular wire is the weld won't entirely be stainless. The two metals blend forming a sort of alloy and unless treated it will rust. I work with stainless steel creating art pieces and I weld it with mild wire.

    I wouldn't weld a sink with mild wire unless you did it from the outside..
     
  7. Hitch

    Hitch Moderator Staff Member

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    If its a commercial food prep area, you shoulnt even consider doing it from the outside with m/s wire.
     
  8. Ram48 Member

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    Well I got it done The sink cracked on a bullnose edge (it looked like someone stood on it to reach a shelf above.) I found .030 SS wire, I know it is kinda heavy I wanted .o23 but on a Sat. afternoon I guess beggars cant be choosey. set the hobart 135 to its lowest settings and made a series of short welds. I had two smal blowouts but got lucky and filled them in. It was discolored like you guys said it would be using O2/Argon. but it has held up for over a week of use. I wish I could have made it look a lot better.
    Thanks again for all your help and patience with this new guy.
    Ray
     
    Last edited: Mar 7, 2006
  9. malcolm

    malcolm Hej!

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    Out of interest - my stainless steel exhaust welded with stainless wire but argoshield gas if starting to get a little rusty around the heat affected zone. Discoloration of the weld didn't seem to be a problem but after welding there was some carbon around after weld that came off with a wire brush.

    Would pure argon, or some argon helium mix for a shielding gas have reduced the rust?
     
  10. Hitch

    Hitch Moderator Staff Member

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    Thats called 'carbon pickup' Malc.
    What argoshield are you using, light?
    It can be eliminated with the use of a gas such as astec sx(argon, oxy and c02,) or prodarc 98%argon, 2%oxy.
    Lower the c02, less carbon pickup i believe.
    Both air products brand names, obviously boc do an equivalent.
     
  11. Metalúrgico Member

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    don't use a wire brush on stainless unless it's specifically made for stainless steel. as you should know, stainless is much harder than mild steel, so when you use a regular old welding brush on stainless, you're leaving mild steel fragments in the stainless. ..which is what's rusting. if I'm not mistaken, the brushes made for stainless are brass. If I'm wrong on the brass part I'll find out.. but I know you're not supposed to use any old brush on stainless steel.
     
  12. malcolm

    malcolm Hej!

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    That would explain it - I polished everything up with a bench grinder fitted with a mild steel brush. The rusty looking bits correspond with the areas I've wire brushed. Oops.
     
  13. Hitch

    Hitch Moderator Staff Member

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    You can get brushes with ss wire aswell as brass.
    I tend to use scotchbrite instead of wire brushes.
     
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