I was kinda thinking of doing something like that. But the drop loop is a pretty tight bend and I was worried about getting a kink.What radius and wall thickness? If you can get away with a large radius, you can just bend it by hand (slowly) around something large and round. I bent the 1' x .049" top tube on my bike using two 18" particle board discs routed to form a half round. See pic. I also used this to bend the chainstays.
I'm thinking that would crack the pipe he was trying to bend. Sand would probably be better to fill it with, tightly packed sand would help keep it from kinking.Have you tried to fill the pipe with water and freeze it then bend it?
That was also something I was thinking about. There is a small muffler shop that I have bummed scrap exhaust pipe from. The downside is that I won't have control, as most of my work is trial and error.You can go to most any small muffler shop & they'll be able to bend it for you (most likely for free.)
Have you tried to fill the pipe with water and freeze it then bend it?[/QUO
One thing is for sure it would be no problem freezing the 6 ft tube. Just leave it outside for an hour. I will try that method on some scrap tubing just to see how it works out. I doubt that it would crack the tubing if it was filled and left veritical while freezing with the top open.
In my teen age years I did sand filled bending but results were mixed 60-40 failure to sucess. More than likley due to lack of skill.
I saw some bending mandrels for 1" dia tube. However the shipped cost was around $200.
Two much for just one bike build.