T joint, .120" wall thickness 3 x 3" square tube. What are the parameters for single medium to heavy pass of .035 CO2 vs. multiple passes of say 3/32? Or even multiple passes of l035? Is there that much larger HAZ? Much more distortion or pulling due heat and cooling? What would be the best way to go for strength? Is there any rule of thumb for big passes vs. multiple passes?
Steve
0.120" wall is still very thin. A single 1/4" fillet weld is plenty.
We don't usually got to multi-pass fillet welds until you get up to
3/8" fillets.Just slow down, keep you wire stick-out short, and use a slight weave.
I beefed it up with lots of crossbracing, and used my new used Miller M225 ac welder. All in all, I used 6011, 7018, ERS-6 .035", and .035" fluxcore. A LOT of welding, needing to beef up my trailer. Will post a pic soon.
I did see that a nice weave with the .035 gave a large beefy looking weld, just take time at the edges to burn in the base metal. I shall keep an eye on it, and am adding three 3x3x.375" cross members under the bottom just because. It is overkill right now for hauling firewood, but I wanted to beef it up for my 5,000# backhoe. I got a couple of other small things, but it's almost there.
Steve
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