This is my frame building fixture that I designed and fabricated. It has some unique features. The contact points are adjustable side to side, so that you can be sure that you are holding the frame components in the correct alignment. I designed a special tool that allows me to check the alignment of the tubes while they are held in the fixture. That is illustrated in these images, but it’s hard to understand unless you’re seeing it in person. Stop by if you’re in the neighborhood, and I’ll run it down for you.