weld shrinkage

Would acetylene's larger heated zone make it better than stick to weld a tee joint in 1" square tubing that should be as square as possible?
The shorter leg will be the upright that planks are clamped against to saw the top edge, so 'square' in this instance is to woodworking tolerance and 'possible' means for a hobbyist.
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On 7/6/2019 1:59 PM, Jim Wilkins wrote:

Center tack and weld the flats first . Then center tack and weld the inside corners a quarter at a time alternating sides . Good clamping can't hurt . And small beads are going to pull less than big ones . Don't you have a wire welder ?
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I would weld the outside edges, rather than the inside corners. Maybe a tiny bit weaker.
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That's what I thought. I bought the acetylene tank after the blacksmithing class last year and haven't gas welded anything this large yet, and want to try on something non-critical like this tee that I can saw apart and do over.
Based on experience with similar square tubing joints on the sawmill frame I plan to weld the outside flat joints but not the inside corners, then grind flush and add triangular gusset plates.
The sawmill's open-ended ladder frame stayed straight until I welded the rungs' inside corners, then cooling shrinkage pulled the outer ends together and I had to jack them back parallel.
The ladder frame ends have to be open to install the bandsaw blade.
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On 7/8/2019 11:03 AM, Jim Wilkins wrote: ...

I once stick welded a 3/8" plate to another 3/8" plate, in a tee. There was only inside corners & I was astonished how much the plate was bent by the cooling weld. When you consider how little leverage the weld has, the force has to be extreme.
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