Here’s a progress report of sorts. First, the RG45 rods made a HUGE difference in the quality of the weld bead I was able to run – for the better. So that, in itself, is a giant step forward for me. The bead I ran (right angle butt joint between two 6” long pieces) looks very decent.
Next, using the RG45 rods, I welded a butt joint between the ends of two pieces of ½” square stock. I ground the ends so that, when the two ends were pushed together, there was a V-shaped valley down to the center from two opposing sides (probably about 45 degrees). The welding process seemed to go OK (but what do I know). I ground away most of the excess and then lightly forged the joint as you described for a couple of heats.
The joint looked fine. I decided to see if I could forge it more aggressively, since I might want to do that in attaching reins to jaws. I tried turning the ½” square bar around the weld joint into a round rod (with orange/yellow heat). At first it seemed to be responding OK, but then I could see a crack developing, and then it cracked in two.
So the question in my mind at this point is whether the weld failed because welds don’t like to be forged aggressively, or did it fail because of my lousy welding technique.
Is the process I described a good one, or is there a better way to do a butt joint weld?
Next step: I’m going to do the weld again as I described above, but this time I won’t forge it. Instead, I’ll cut it in two with a hacksaw to see what the weld looks like. That may tell me something.
The learning process continues!