On Sat, 24 Jul 2010 18:51:00 -0500, Lloyd E. Sponenburgh wrote:
On Sat, 24 Jul 2010 16:09:10, James Waldby [wrote]:
I realize you (LS) have already made the springs but am posting anyway
about a possible method.

All good info. Thanks. I'm compiling a mini "library" of
spring-winding stuff.

As time permits, I will challenge the math you've presented. It looks
rational and reasonable.

I'm still confused about the "knee", though, because it's _really_
there. Perhaps it's explained by the math...

The thing to challenge is the model, e = k*A*D (e=springback angle,
A=total angle wound, D=diameter wound, k=material and units constant)
which is linear in A and D. That agrees with some of the online
references I looked at, but not all. If I could have read the
exponents in the four equations just before halfway thru
http://www.thefabricator.com/article/tc/roll-forming-high-strength-materials
I would have tried to use a non-linear model.

--
jiw