[MarkL]

Your main weapon for not burning through on tacks is to get a very small tack. For that you need to have hands of stone, the eyes of a brain surgeon, and the foot of Steve McQueen---a fast one.

I'd rather look like Steve McQueen than have his feet, but I guess I'll take what I can get.
First things first, how did you take those photos, smartphone or camera?

[MarkL]

I like the idea of sleeving the joint, but my preference would be to cut a small longitudinal slit out of the sleeve so it'll compress and fit inside the tubing. Then leave a small gap between the pieces of pipe. It'll be an open root joint with a backing strip. Should work well.
Larry

That might solve another problem, which is getting the two halves of the gate back into alignment. There was a lot of stress in the tubes and when I cut them, they sprung out of alignment. I was going to clamp them to a large table to get them into alignment to tack them. The sleeve might be strong enough to hold them all in alignment while I tack them.

[Oscar]

Your main weapon for not burning through on tacks is to get a very small tack. For that you need to have hands of stone, the eyes of a brain surgeon, and the foot of Steve McQueen---a fast one.

I'd rather look like Steve McQueen than have his feet, but I guess I'll take what I can get.
First things first, how did you take those photos, smartphone or camera?

Smartphone.

[5th Street Fab]

I'm butt welding 20ga round steel tubing, 1-5/8" diameter. I'm fine once I get it tacked up, but I'm burning through on the tacks. I could use some help on:
1. How do I tack without burning through.
2. I'm having a hard time seeing the joint once I get it tacked up. Any tricks to make the joint more visible.
3. I can only weld short sections before I need to rotate the tube because I can't keep the torch at the right angle on such a small diameter. Other than buying a rotator, is there any way to get my hand to more quickly change angle as I come around that small diameter tube. I'm tempted to try putting it in a vertical position so I could more easily move around it as I weld.

Hey so I used to do lots of thin wall tubing. #1 thing is prep. Belt sand both sides perfectly flat so when you butt them up there is no gap at all. Deburr both inside and out.

They need to be exactly in a line too. Placing them in a piece of angle iron helps but I prefer to put a tube I am vice and slide the pieces I'm tacking over it.

To tack I set my machine to about 25 amps. Then hold my tungsten as close as possible to the piece. Romp on the pedal as fast as you can and let off. Like your tapping your foot. If it didn't tack then do what we call a double tap. You just tap the pedal twice in a row really quickly. Don't use filler, at least until it's tacked.

Then to weld it just leave it on the tube in your vice. You can weld a 1/4 at a time or whatever you want then spin the pipe and go again.

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[zank]

See if a friend or your local weld shop will clip off some 035 mig wire for you. It should take much. On Monday, I'll try to remember to mock up some tubing and see if i can offer some settings. The SW200, has pulse, yes?

[MarkL]

Hey so I used to do lots of thin wall tubing. #1 thing is prep. Belt sand both sides perfectly flat so when you butt them up there is no gap at all. Deburr both inside and out.

They need to be exactly in a line too. Placing them in a piece of angle iron helps but I prefer to put a tube I am vice and slide the pieces I'm tacking over it.

I've got good prep on the parts, still practicing on samples that I cut out of the gate. I'm using a vise.

To tack I set my machine to about 25 amps. Then hold my tungsten as close as possible to the piece. Romp on the pedal as fast as you can and let off. Like your tapping your foot. If it didn't tack then do what we call a double tap. You just tap the pedal twice in a row really quickly. Don't use filler, at least until it's tacked.

Wow, 25A, that's really low. I normally hit the pedal like you're describing for thicker material, so I know what you mean.

[MarkL]

See if a friend or your local weld shop will clip off some 035 mig wire for you. It should take much. On Monday, I'll try to remember to mock up some tubing and see if i can offer some settings. The SW200, has pulse, yes?

I can get some mig wire from a friend. SW200 has pulse from 0-20pps, %on and background are fixed at 50%, no adjustment. Thanks very much, I've heard Jody mention you on his videos. I did triathlons for years, had one of those old Schwinn Paramounts with the beautiful chromed lugsets and Campy record. I hit a woodchuck going about 40 and bent it into a pretzel.

[MarkL]

I got back to working on this. Decided I needed to put a sleeve inside the tube. Both of these pieces are the actual gate material, one is slit to fit inside:



I used 1/16" filler with 1/16" tungsten and pulse 1pps. It was still pretty touchy to keep from burning through, but I can make this work:



I don't have a photo, but I switched to .035" filler rod and that helped, but I didn't have a smaller tungsten. I'll try the smaller filler with a .040" tungsten next. I'm running out of test material, so I'll have to weld the real thing soon.