Originally Posted by
ftwelder
The customer just got it together. Ill ask if I can share the geometry.
Depending where the crack is, heat treating may not be required or even desirable. When aluminum get's to the 950, the frame is so soft that they can be easily damaged. It's very difficult to keep them from moving enough to cause problems. I have seen tubes sag as much as 2" in the center so you need to have a lot of stuff around to get it straight.
I have a complete alignment and tube straightening set-up near the quench tanks. I get about 30 mins make them (six at a time) straight before they start to get stiff.
Thanks. The crack is at the weld at the vertical member and the seat stay yoke. There is also a hairline crack that has been there for a while I think running vertically at the drop out. The one on the weld looks pretty bad.
Haha, those were just some ideas some fella was tossing around. He's more of a computer guy than a welder. I'll look into the absense of heat treat, but the bike designer, NOT the fabricator, is the one who highly recommended heat treating in that area.