steel tubing cracked, stressed

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Hello all,Please look at the attached photo. It's the end of a table tennis barrier that has been bent to the point where it cracked the steel tubing. I'm a hack arc welder and I have a lincoln arc welder that I've had for 30 years. My welds usually hold but they don't look pretty. I recently bought an oxy-acetylene setup for hvac brazing but have not used it yet.The tubing is very thin but if I set my Lincoln to 40 if might not burn right through it. I've never done any oxy-acetylene welding but I'm willing to give it a shot. Should I do the arc welder or oxy?What kind of stick should I use with the oxy?I'm a newbie to oxy and a hack with the arc but I love welding.  Any advice would be greatly appreciated.ThxSlash Attached Images
Reply:You sure thats steel tubing?Do not stick weld that with your arc welder. You will destroy it...Way too thin of material.The only way I would try to attemp repairing that piece would be tig welding it.You might be better off just replacing it.JasonLincoln Idealarc 250 stick/tigThermal Dynamics Cutmaster 52Miller Bobcat 250Torchmate CNC tableThermal Arc Hefty 2Ironworkers Local 720
Reply:If its just mild steel, get some steel filler wire and give it a shot with your OA torch, It shouldnt be too hard if you take your time and watch the heat.
Reply:I have repaired tubing similar to this using OA.  You really need to practice a bit first though - see if you can find some scrap laying around that you can try first.When it is this thin, if you aren't already comfy with OA welding you might be best off by inserting a smaller diameter tube inside the broken part (or on the outside) then use plug welds or cut notches and weld through those.  That gives the heat a little more room to disperse than if you try for a butt joint just using the broken part.OA welding really rocks for thin stuff - you get beads that need no clean up if you are careful - they can look almost as nice as TIG!I can't stress the "practice" enough though - you need to figure out which tip and what technique this particular material needs, practicing on the part will leave you with a mess.Hobart LX235Victor 250 Oxy-Acetylene Rig (welding and cutting)Bobcat 773F-350, 1999, 4x4, 16' 10K# trailerOutdoor Wood Burner - 10 cords/year
Reply:You can try o/a and a coat hanger for filler wire. if not try spraying some 6010 long arced
Reply:I'd sooner bend a piece of 1/2" EMT, and replace the whole part, then try to weld that, and I HAVE a TIG welder plenty capable of welding on stuff that thin (heck, I repaired a pair of titanium glasses once).
Reply:Looks like EMT to me too."The things that will destroy America are prosperity at any price, peace at any price, safety first instead of duty first, the love of soft living and the get rich quick theory of life." -Theodore Roosevelt
Reply:If the material bent enough to crack it, the design was poor and the same thing will happen again if things aren't changed. Either much heavier material for the entire structure, a much more rigid design, or both, appear to be needed. New material, at least for the bad sections, will probably be cheaper then the time and gas to repair the breaks, where the existing tubing would have to be reformed into circular sections before welding.
Reply:The gas cost will be pretty low - this should take less than a minute to weld back up.  The real utility is in the training - good practice for handling thin material welds so that when the difficult to replace part comes along you will have a chance at getting it done properly.Hobart LX235Victor 250 Oxy-Acetylene Rig (welding and cutting)Bobcat 773F-350, 1999, 4x4, 16' 10K# trailerOutdoor Wood Burner - 10 cords/year
Reply:Originally Posted by gwileyThe gas cost will be pretty low - this should take less than a minute to weld back up.  The real utility is in the training - good practice for handling thin material welds so that when the difficult to replace part comes along you will have a chance at getting it done properly.
Reply:Surprised nobody picked up on this sooner, but you bought an O/A set up for HVAC brazing. If you are familiar with HVAC brazing then this will be the same technique basically. Just use a steel wire(coat hanger wire, or small welding rod with flux removed) instead of brazing rod, although brazing rod will work just fine too in this case. Use the smallest brazing tip for best heat control on this thin tubing. Is the one pictured the only one to repair, or is there more? Either way it won't matter, just braze or weld it with the O/A rig.