Just a couple of weeks ago, I found some very small springs that
look just like the bigger tubing bender springs that I've seen at a
local hobby store (one that caters to the radio control airplane and
car constructor crowd).
The kit is made by K&S Engineering, it costs $3.19, and has 5
springs that are flared on one end and sized for bending tubes from
1/16" to 3/16" o.d.
They work quite well! The springs support the outside of the tubing
and keep it from kinking or flattening, and do not mar the tubing at
I googled and found them on ebay and on an online hobby site if you
can't find them locally - I entered "k s engineering tubing bender
321" (the kit part number is #321) into google and the first two hits
had places to buy it from...
Blue Dog Forge