O/A Welding 4140 Bar

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I need O/A weld two pieces of 4140 bar stock together. One piece is approximately .5 x 1.0 in and the other is .375 x 1.0.  They will be turned 90 degrees to one another with the flat size of the smaller bar resting on the edge of the larger bar. Can this realistically be done with an O/A torch and if so what type of rod is preferred?  Any other ideas or thoughts about welding this material would be appreciated.Alan
Reply:Oxweld #32 (you can find this tuff here.. http://www.aircraftspruce.com/catalo...enus/nme27.php )or a tig rod like er70s2 with no copper coating would work.  Id start with 3/32 or 1/8 and then a #5 or (getting up in the CFHs) #6 victor nozzle.Last edited by Doolittle; 01-03-2007 at 05:35 PM.Various GrindersVictor Journeyman torch200cf Acet. 250cf oxygenLincoln 175 plus/alpha2 gunLincoln v205t tigLincoln 350mpEsab 650 plasmaWhen you can get up in the morning, Its a good day.Live each day like its your last.
Reply:TIG rods with the gas torch don't work too well.  They don't wet out very well.  RG60 is the preffered rod for chrome moly work and requires no post weld heat treatment like the ER70 rods do.
Reply:Don't forget that it can be brazed, too.
Reply:unless you need a high strength joint and im thinking with the material thickness it would be best to weld it. sorry cant help with the filler selection..
Reply:I got to thinking about this some more, Why not just take a peice of 3/4"x1"x 2" and grind out the shape you need.  It would be stronger.  Im working with some trying to get good penetration and keep the dagone thing from melting (Im using mild steel), and it is difficult.  Gonna try dropping the tip size down to a 2 and try again later, its a challenge.  Disregaurd the previous post as it was overkill.  I did it with a #4, but it was a pretty cold weld and the puddle spread was quite large.   Yea, butt welds are a no no for brazing..Various GrindersVictor Journeyman torch200cf Acet. 250cf oxygenLincoln 175 plus/alpha2 gunLincoln v205t tigLincoln 350mpEsab 650 plasmaWhen you can get up in the morning, Its a good day.Live each day like its your last.