[TheForge] Re: helical railing calculations

[Andy Vida]

Bob Ehrenberger wrote:

> But Every time I try to use my tire bender I end up with a helical sort of
> effect.  The problem I have is I am trying to do it by myself and I can't
> hold the bar straight and turn the crank at the same time. If the bar cross
> tracks on the rollers it gets a helical bend.

	Does the bender have guide rails?  If not, you might want to
	consider installing a set.  Just an adjustable "throat" if 
	you will, to guide the in- and out-feed of the rolls for
	correct alignment.  Put in the stock, and crank away.

	If you do, be certain to build them VERY heftily because
	the forces are large and wimpy guides will distort and
	bend.  Try using 1" square for the adjusting rails in a
	square hole and 1/2" or thicker for the actaul guide rails.
	The actual dimensions would really depend on the size of the
	bender, but don't be bashful about heft.