notes

aluminum brazing

If the stock needs to be bent:

Not all aluminum alloys can be annealed...not sure which ones, but I don't think they can all be softened. Also, they need to be work-hardened again to stiffen up...if you anneal a piece of aluminum and bend it once, then leave it alone, it'll still be soft. I'm not sure if putting it in a brake will be enough to work-harden it.

For the magic marker method, just run the torch over it until the ink burns off. That's roughly the same temp that the soot layer method reaches. The ink burning off is the indicator that it's ready.

Solution heat treatment for 6063 involves heating the part to 970 +/- 10 deg F for a period of time, depending on maximum thickness, quenching ... usually in water ... then the part must be aged it at 350 deg. for 8 hours to regain T6 strength.

Another option is to warm bend your tubing. At 350 degrees the elongation of 6063 T6 will be greater than fully annealed material, and will bend easily. It will then return to full strength when it cools ... if the time at temperature is short ... under 30 minutes. Even if your process isn't perfect, I have used an O/A torch and Tempilstick, the resulting strength will be better than an annealed part.