In my BJ (before jig) building I tried a few "hockey stick" arrangements and decided that what I liked best. I ended up doing the ST to shell 1st then add the TT, this is the 1st half of the main frame. 2nd half was the DT to HT. I found this made the DT length/BB miter easier to control. Back then I hand mitered each joint as I went along (although as I got better I would miter both ends of the TT and DT but a couple of mms long for the in situ final fit up). I mostly pin then tack then correct and complete the braze and correct again. I would fit the two halves and often find that I had to juggle the remaining miters a tad for the best fit up. Using only lugs back then I would use the through hole socket of the DT/BB as a fudge for the last bit of dimensional alignment, thus sometimes I was pleased that I had mitered the DT a tad long.

To this day, and even with a nice jig, I still attach the ST to the shell first.

It was the "prefab" issues of slightly bowed tubes, miter phasing/indexing (this before metal split tube clamps) and the resulting not perfect mating of the two halves of the main frame that made me start to set up the entire main frame before any tacking or complete brazing. This is now all I do, set up each joint in the jig one at a time then as the full triangle then tack, correct and complete braze. If I had no jig I would use a flat surface and some sort of riser blocks to position the tubing. But I would still set up the complete triangle as a unit (excepting the ST/BB which would already be done). Andy