Welding 20ga to 1/2" rod

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I'm using a 210v Hobart, .035 wire and CO2. I have to weld the edge of a 20ga rectangle to a 1/2" rod on a larger piece I'm making. It's not art, needs to have some strength to it.I've tried directing the weld onto the rod only, letting the puddle edge drift over to the 20ga but that blows holes every time. And I've tried settings a little lower but the same thing happens.The only way I can figure out how to do it is dial the welder down as close to the 20ga requirement as I can, weld a series of spots then crank the welder back up and weld the outside edge of the lower temp welds to the 1/2" rod.I put a test piece using my method in the vise and tried to tear it apart and it held. I couldn't do it.I'm wondering if there's a better method I should use? Or maybe mine is good enough. They're ugly welds but I have many grinders.Last edited by JD1; 11 Hours Ago at 04:25 PM.
Reply:

Originally Posted by JD1

I'm using a 210v Hobart, .035 wire and CO2. I have to weld the edge of a 20ga rectangle to a 1/2" rod on a larger piece I'm making. It's not art, needs to have some strength to it.I've tried directing the weld onto the rod only, letting the puddle edge drift over to the 20ga but that blows holes every time. And I've tried settings a little lower but the same thing happens.The only way I can figure out how to do it is dial the welder down as close to the 20ga requirement as I can, weld a series of spots then crank the welder back up and weld the outside edge of the lower temp welds to the 1/2" rod.I put a test piece using my method in the vise and tried to tear it apart and it held. I couldn't do it.I'm wondering if there's a better method I should use? Or maybe mine is good enough. They're ugly welds but I have many grinders.
Reply:Yeah I tried that. The edge of the rectangle instantly dissolves no matter how quick the zap is. And like you said, if it's too quick it won't get into the rod.
Reply:Do you have a copper rectangular piece you could clamp to the back of the sheet to control the heat, reduce burn-through?Do you have smaller wire? Lower volts needed, lower amps > lower heat, better puddle control?  I assume you don't have 75/25 gas that would give a softer arc.What about a gas torch and brazing the joint instead?
Reply:I've got .024 wire but wouldn't I have the same problem? Enough heat to get into the rod and the 20ga vaporizes.Brazing... that's an idea. I've never done it, I assume you can braze with mapp gas and a regular torch? The rod is rebar...any issues brazing to it?
Reply:You need to fo what 12v71 said, but high heat to burn into the 1/2" rod, and barely weave the puddle into the 20 ga. In reality your only welding the rod and tacking the sheet. Use a backing piece against the sheet to help draw the heat out of it.
Reply:If you haven't already, grind the edge of the rebar down so it's clean. That might help with the mig or brazing. Rebar isn't the best steel to be welding. I would definitly switch to the .024 wire. That would help also. I think you just need to practice the zapzap technique some more. Keep the gun at 90* to the rod and try to wash the puddle down to the 20ga. Also is the 20 ga clean like making a swipe on it a flap disc.Ol' Stonebreaker  "Experience is the name everyone gives to their mistakes"Hobart G-213 portableMiller 175 migMiller thunderbolt ac/dc stick Victor O/A setupMakita chop saw
Reply:Annoying...I just ran out of gas! Will get back on it early next week when I can get a fill.
Reply:Are you sure the 20ga is steel?NRA LIFE MEMBERUNITWELD 175 AMP 3 IN1 DCMIDSTATES 300 AMP AC MACHINEGOD HELP AMERICA!"Those who would give up essential Liberty, to purchase a little temporary Safety, deserve neither Liberty nor Safety.” BENJAMIN FRANKLIN
Reply:Fuuuuck!  20 ga. to 1/2" I'd throw the project out the back door!  Its doable but frustrating.It seemed like a good idea at the time!
Reply:Seems like you are butt welding the 20g to 1/2?  Can you do a lap? If it must be butt then is it snug fit?
Reply:

Originally Posted by JD1

I've got .024 wire but wouldn't I have the same problem? Enough heat to get into the rod and the 20ga vaporizes.Brazing... that's an idea. I've never done it, I assume you can braze with mapp gas and a regular torch? The rod is rebar...any issues brazing to it?