BENDING:
OK.. For easy to obtain/use tubing benders try your local auto parts chainstore. Go to Autozone, Checker/Schucks/Kragen, Napa, etc and tell
them you're looking for a brake-line bender.. It'll be in the tools section
with the brake repair tools (<$20 for a decent one that does 1/8" - 3/8")
or you may be able to borrow a loaner after paying a deposit.
These are a "shoe" type bender and are OK for 0-90 bends in Al/Cu/steel.. Here's Harbor Freights $7 version so you have an idea what to look for.
http://www.harborfreight.com/cpi/cta...temnumber=3755
For more complicated bends you want a spring type bender or a tubing roller.
The spring type benders usually look like a screen door spring with a belled end.
If you cant find one look for a screen door spring, casement window spring
or other spring the right I.D. to slip over your tubing
Here's how to build a tubing roller with a drill press and a few other tools.
Build a tubing roller link
http://www.motherearthnews.com/Green..._Tubing_Roller
UNBENDING
1:The Mandrel.
Best thing I can tell you to do is find a piece of the hardest steel bar you can, a hair
smaller in O.D. than your tubing I.D. and longer than the section of tubing you want to work.
Taper one end to 50% of the O.D. for a length of ~3 x O.D. and finish it with a rounded point.
If you're not using seamless tubing you may have to grind a notch for the seam to lay in
along the length of the bar or use a smaller diameter bar.
2: The Smoothers
Refer to
http://www.motherearthnews.com/Green..._Tubing_Roller
for instructions on how to make the 2 rollers you will want to smooth the
tubing against the mandrel.
You need to make the cranked roller and one of the follower rollers.
3: The Frame
Refer to the diagram for the tubing roller and make a frame that will hold
your 2 rollers against opposite sides of your tubing.
Remember the adjustment slots for the cranked roller to set your roller to roller distance.
4: How it works
Straighten your tubing as much as possible and insert the end of the mandrel into it.
Keep straightening and pushing until you have enough of the mandrel into the tube
to allow for the length of tube you want too work.
Run it back and forth through the rollers several passes rotating it 30-90 degrees/pass.
With any luck you'll now have a piece of tubing that now has a uniform exterior finish.
Did I miss anything?
Bleeptech