Cu to SS welding

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Can I do that with a 88amp Lincoln Mig machine? Or is brazing the way to go?I will eventually get TIG machine but not right now.ThanksBR
Reply:I believe you should braze it, but not all SS alloys take kindly to brazing, I'd have to drag out my book to get you all the info.  Is this joint going to be structural? If it is, I'd be leary of doing it. any more info? Alloys involved? Application? thicknesses? stresses the joint will endure?   All of these are factors to consider.Anyone else have input? I am interested in this dissimilar joining process also.We need to protect Freedom of Speech, otherwise, how would we know who the A-holes (like me) are.
Reply:BR,thats the way im heading to. I have the black flux and the Safety-Silv56 Solder.This is made by JW Harris co.  Another email friend said he used a Braze 452 silver solder. I fnd these web links..http://www.handyharmancanada.com(brazing manual) and other infoand www.myggyweld.com, Seattle area.I thght it wld be neat if i cld mig the Cu. Seems like ive read that that is better done witha TIG machine.O well.
Reply:don't know exactly what you are doing, but harris has a web site also. I have done it with silphos 10, and it makes a pretty sttong joint, but I wouldn't use it for structural use.
Reply:High nickel content nickel/silver rods work well for brazing stainless.  The working temperature might be high for joining copper (1600-1750*F), but depending on the joint you're making it might be do able.  Nickel/silver rods can create a joint that is every bit as strong as a welded joint, 60-70ksi, and can be used in structural applications.  Nickel/silver brazing has been used for many years to join the chrome moly tubing found in bicycle frams and aircraft frames.
Reply:If you tig it, it will likely crack right down the middle. I used to do a lot of CuNi.   One day, we had an outside inspector there to witness a hydro test.  One coupling had been overlooked and was only tacked in.  We were in a big hurry to weld it up.  One guy ran for leads, one for the wire, etc...  all hands on this one task.  I was the one to weld it.  One of the guys was handing me wire, and gave me a piece of stainless.  The weld cracked and cracked and cracked.  I had to weld it with CuNi and grind it out about 5 times before I had gotten enough stainless out of it that it wouldn't crack.
Reply:Im gonna try some ss 304 keg material to some Cu and see what happens.Ill try and rem to post the results. Seems like i read you can TIG Cu with no probs..BR
Reply:Keep in mind that even IF it doesn't crack, you may not have $hit for tensile strength.  It could break under pressure.  I'd not reccomend it on anything important.
Reply:................IF it Catches...Let it Burn