MIG brazing with silicon bronze wire?

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I have seen a demo of MIG brazing but it's been quite awhile. I believe he used argon gas and .030" silicon bronze wire. Looked just like MIG welding but the joint came out brazed not welded, very cool. Anyone have any ideas as to machine settings or gas flow rates for this process?metalmagpie
Reply:A couple of decades ago, I set up a GMAW operation to braze weld a tool steel plate to mild steel. As I recall all the parameters were the same or nearly the same as the spray arc settings which I specified for the ER70S-6. We were running .045 and yes for the silicon bronze, we used straight argon.
Reply:in the late 60's i bought silicon-bronze wire welders for all of the ford assembly plants. they were used for cosmetic welds--roof to a-pillar , roof to quarter panel,upper back panel to quarter panel and on some models,the lower back panel to quarter panel. these were only about a 1/4 inch on surface  and about the same into the rabbit. easier to grind and less distortion than steel wire. later when e70s-6 steel became available,we switched to it due to cost.
Reply:oops---getting old ,69 yesterday. anyhow slight memory lapse.the bronze was used to replace hand brazing in those locations. some of the plants were even using in-line fluxers so they could buy bare rod.
Reply:what is mig brazing? i cant picture how to set up a wirefeeder to "run cold" and keep the heat low enough to be brazing ...
Reply:we'll likely stir up some disagreement here,but i believe the base metal melts when using bronze wire on steel.therefore,by definition,it's welding not brazing.
Reply:true brazing is a real thin deposit into a capillary space. i've heard of braze welding as  building up braze metal to filla void but its still not melting=welding.  mig brazing...? why not call it welding with sillybronze filler?
Reply:Welding melts the base metal, and adds more of the same metal to the weld pool. Brazing does not melt the base metal, and adds different metal to the joint.MIG brazing is just what you think it might be - brazing by pulling a trigger. I've seen it done and it works very well. I just want some idea as to setup before I go wasting silicon bronze wire, which doesn't grow on trees.
Reply:Originally Posted by metalmagpieI have seen a demo of MIG brazing but it's been quite awhile. I believe he used argon gas and .030" silicon bronze wire. Looked just like MIG welding but the joint came out brazed not welded, very cool. Anyone have any ideas as to machine settings or gas flow rates for this process?metalmagpie
Reply:"Welding melts the base metal, and adds more of the same metal to the weld pool". then i guess using nickel or stainless rod on cast iron isn't welding in your book .