Help Welding Stainless

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OK guys, go easy on me here...I'm about to ask some stupid questions and really show my ignorance(s).  A friend of mine has asked me to weld (fix) some brackets from his sailboat.  From what I understand, the material is stainless tube, welded to a 0.125 SS plate.  The brackets reinforce some steps on his boat and they will not be seen.  Therefore, he is not concerned with the cosmetics.  I've never welded stainless before but I have a Miller 210 (w/C25), a Lincoln AC buzzbox, and oxy/acet.  Ok, here's where the stupid questions begin:  Which out of the three would be the prefered method?  If MIG, will the C25 work?...and what wire should I use?If Stick (can this be done)?  What kind of rod?If O/A?  What kind of filler? What about flux?Remember...please go easy on me...your advice would be greatly appreciated
Reply:Stick or mig will work.  I have never used stainless sticks, but I have seen the results...they aren't bad...in fact, they are pretty nice.  Mig will work also.  It's pretty common to mig stainless these days...here is a link to the lincoln dohicky that describes the process.http://www.lincolnelectric.com/knowl.../migweldss.aspCheck your PM'sSmithboy...if it ain't broke, you ain't tryin'.
Reply:TIG would be the best method, but in your case probably STICK since you can buy just enough electrodes for the job and not spend too much.  With MIG you'd have to buy a spool of wire and would do best with a gas like 95%Ar/5%CO2.
Reply:Smithboy and Pulsar, thank you very much for the input.  Sounds like stick is the way to go.  I actually have 1lb of stainless electrodes that I bought a while ago on sale...thought they might come in handy some day.Smithboy, I noticed your in Carrolton, GA...I live in Snellville and work in Norcross.  Small world eh.Thanks again guys...it is greatly appreicated!
Reply:+1 on the stick welding.If you are OK with stick, that is.  For a small(er) job, there will probably be less cost in supplies for some stainless rods than the needed MIG supplies.For MIG, you -could- probably weld it up with plain steel wire and C25.  But then the welds won't be stainless.To do it right, you need the right materials and supplies.  For stick, that just means getting the right rods.  For MIG, it means getting the right wire AND getting the right gas.  And C25 is generally not the right gas for MIG on stainless.pulser must have gotten tired of posting the link to recommended gasses for GMAW.  Here it is again :  http://files.aws.org/wj/2006/02/wj20...j200602-46.pdfSummary of gas for GMAW on stainless:  98-2 Ar-O2, 95-5 Ar-CO2 or so (low CO2 mixes), or tri-mix.  High CO2 percentages lead to excess carbon in the weld, which makes the metal not really stainless anymore.Oh, and you should try and find out the alloy of stainless the work pieces are and get the appropriate rod/wire for that alloy.  Stainless is not all the same and you can't necessarily weld any-n-all stainless with any old rod/wire.Oh, and if the brackets "will not be seen", to me that means that they are at least partially hidden.  Which on a boat/marine environment means they could be a little bit 'forgotten', so to me that means they should be done extra nicely to minimize the welding related corrosion potential.  So use the right gas if doing GMAW, use the right filler, and clean and prep the work well beforehand and you should make the welds as smooooooooth as you can.  Smooth and polished steel corrrodes less than rough steel (we'll ignore parkerized steel in this discussion).  It has to do with all the little surface irregularities acting as localized corrosion trap or nucleation points.  Add in a marine environment with moisture and salt, and things really should be done right to minimize corrosion issues.The really picky might want to smooth, polish, and then electropolish the stainless.  And passivate it as well.
Reply:Originally Posted by jwilsonSmithboy, I noticed your in Carrolton, GA...I live in Snellville and work in Norcross. Small world eh.
Reply:MoonRise, thank you for the information.  I'll definatly go with the stick because I'm not sure that I want to invest in another gas for this one job.  I'm pretty comfortable with the buzzbox so hopefully all will go well.  Attached is a pic of the steps...Smithboy, I do remember that commercial   Ya know, most people drive down 78 and pass the town of "Between"...between what???  Evidently the town was named because it marks the halfway point between Atlanta and Athens...what will they think of next.Thanks again all! Attached Images
Reply:Think of SS like coffee(mild steel) with cream added. If you really have to you can weld SS with 6013,6011, or any mild steel electrode. For a small job, just go to the LWS buy a pound of 309 rod and stick it.Disclaimer; "I am just an a$$hole welder, don't take it personally ."
Reply:Hey, wasn't it Snellville where the armless guy killed his girlfriends ex with a headbutt the other day??Moral: Never underestimate anyone.Miller EconotigCutmaster 38Yes ma'am, that IS a screwdriver in my pocket!
Reply:Joe H,Not really sure bout the headbutt thing...although, I wouldn't put it past some our redneck residents.  Ya know, there is actually a sign when you enter the town that reads, "Everybody's Somebody in Snellville."  Is that a proud town or what.
Reply:Here you go. I saw it on the news last night here in NW Ga.http://www.msnbc.msn.com/id/20844553/Miller EconotigCutmaster 38Yes ma'am, that IS a screwdriver in my pocket!
Reply:Joe H,Thanks for the link...interesting story.  Resourceful use of the head...sad...but resourceful
Reply:i'm gonna have to disagree, that stainless tubing is usually very thin, i'm not very good at stick welding so i could see alot of problems arising.  is that a hunter?(the sailboat)
Reply:Not really sure about the sailboat...all I know is that it's a 28ft.  He keeps it docked in FL.  Regarding the welding, it turns out he found another guy to TIG weld it (the right way).  I was a little nervous about it anyway after I saw the pic...it doesn't appear to be as concealed as I had imagined.  Anyway, I still learned a lot from all of the information provided.  Thanks again all.
Reply:i'm gonna have to disagree, that stainless tubing is usually very thin, i'm not very good at stick welding so i could see alot of problems arising
Reply:Originally Posted by smithboyPractically nobody knew another city existed past Snellville heading east.
Reply:Quahog RI?Disclaimer; "I am just an a$$hole welder, don't take it personally ."
Reply:Originally Posted by jwilson Evidently the town was named because it marks the halfway point between Atlanta and Athens...what will they think of next.Thanks again all!
Reply:I'm no expert by any means, but I've used Lincoln's 3/32" 309 BlueMax and they run real well at a low amperage, like 40 or 50.
Reply:Zap, good point.  I think that I'm going to find some ss just to play around with...my curiousity up it).  Washman, I knew that Between was named for "between" something...always thought that it was Atlanta and Athens...thanks for the trivia...makes sense.