If I am reading this correctly, the first tack in our progressive movement from one side to the other side of the panel is extremely important. I do not know the term used, but it should hold/pinch/fuse/anchor the entire panel for the subsequent tacks-correct? My only analogy would be in roof framing & how you'd nail one end of a facial board to a rafter; then worm it up flush for nailing the next rafter, and so on. I'm thinking this method of tack-welding from one end, and working toward the other might help me a lot with fitment.
Also, using the "no-gap" method mentioned above, and assuming the panels suck up (or shrink?) into each other as is common, does "planishing" the weld tacks individually and stretching them out need to be almost immediate; while still warm? I didn't see a picture, but I understand this is a common question regarding the valley, and you'd probably answered it before.
I do know how to make a valley happen.
Brad
See picture in link above, planished cold, no cracks. If you want to planish when something is warm, help yourself. Would it help? Perhaps. What I would suggest is it may cause you to rush in your process. If you start dropping things in a rush to grab a hammer and dolly, perhaps it's not much worth the effort. If you want to heat something back up with a torch to planish a weld, you are now introducing more heat, which causes shrinking. Counter productive IMO.
