[airyarski]

Hey Guys,

I'm a beginner welder, so of course I decided to build a small trailer, 4x4 roof top tent style. Build is going fine, except now its time for the leaf hangers. As this is the first real weld that scares me, I'm practicing on a test piece, but its not going great.
The trailer Frame is 2x2 square mild steel at 1/8". The hangers are U shaped, .250 steel. The weld is essentially a lap joint, as the hanger ends get welded. The sides are optional per Dexter's installation manual.
For practice, I've got some scrap tubing, with a .250 flat plate that I'm trying to weld to the "frame". No matter what technique I try, the puddle penetrates the plate on top, and does not penetrate the square tubing underneath. I would have thought the opposite, as the tubing is half as thick. I can lay a beautiful bead, which at best is essentially tacked to the tubing, it penetrates the thicker plate always. I've come at the joint with varying gun angles from 40 degrees to about 70. I've tweaked voltage (higher).No help, I can forcefully break the joint to the tube side. I layed down a straight bead to the tubing without the "hangar piece, just to see what happens, thinking maybe my power was not where I need it, It penetrates the tubing fine.

Any ideas, I'm sure it just my lack of knowledge/technique, but my tool box is pretty limited. I'm using a Hobart 210, 220V, with gas.

Thanks all

[Oscar]

Where are you? I'll go weld it for you

We dont know your WFS, Volts, how much CTWD you are running, etc. You've typed a lot, but told us very little. A lap joint is eazy peazy. Permission to give the important details, with pictures granted.

[airyarski]

Thanks Oscar,

Very kind offer, I'm in Austin though, little far from Laredo.
I'm running a Hobart 210 with 220V. The manufacturer recommends setting 4/40 for 1/8". I've also tried bumping the Voltage up to 5. As far as stickout, not really good with judging. maybe 3/16", but sure my technique is somewhat dodgy.

Appreciate the commentary.

[cj737]

If it were me, I'd weld it based upon the 1/4 thickness focusing the arc on the U hangar. Gravity and puddle flow will bring the fusion to the tubing.

Before you weld that U hangar to the tube, CLEAN THE PARTS COMPLETELY to shiny, bright metal. This is a critical joint, and you need to do all you can to insure proper fusion and strength. Tack the hangar on all 4 sides before you lay a weld. This will insure it stays flat and plumb and square. Welding the underside with only having tacks on the flats will allow the U to pull out of plumb and screw up your spring alignment.

[Oscar]

Yup, what he said. Use the 1/4" settings and clean all millscale completely (don't just polish it with a flapper)
Also, might need to let the bead cool down before you do the rest, as the saturated heat will have an effect on your settings. It will make it too hot and might get blow through. I would keep the gun angle at neutral or push to ensure you are getting into the root.

3/16" is a good CTWD, gotta keep it nice and tight. Oh and welcome fellow Texan. I have a sister that lives in Austin, and yea its a drive.

Good thing you have scrap to practice before you weld the real thing. Do grind out that tack so you can get down to bare steel.

[airyarski]

Thanks Oscar and CJ.

I'll try the higher settings, and get plenty of practice on scrap. Will get er cleaned up before the real thing.