Different way to make Jump Ring Mandrels

I've not been able to find them in any of my tool catalogs.  Can
anybody out there in Orchidland help me?  I would be such a hero
to my students if I could find a source for these jump ring

Since I haven’t seen anyone reply that makes jump ring mandrels the
same way I do. My goal in making mandrels my way is to produce a
mandrel such that I can easily use a jeweler’s saw to cut my jump
rings off without removing the coil from the mandrel. This avoids
problems with the tendency of rings to bend or slip around while
sawing them.

I use various sizes of drill rod. I drill a hole large enough for
the wire far enough from one end that the rod will fit into a drill
chuck. On the other end of the rod, I cut a slit with my jeweler’s
saw about a half inch long. I make the cut before heating to avoid
any problems with hardening of the steel.

Then I braze a bead of brass at the very end of the rod at the end
of the slit and extend the slit back through the bead. The bead is
so I can keep a pressure on the coil against the slit end of the
mandrel while sawing. I shape the area by grinding a slight dip
across the slit in the mandrel as it approaches the bead. The dip
ends by grinding the elevation where the bead starts to vertical.
Finally a grind a bit from the bead opposite of where I ground the
dip. The object being to shape the end so that the jump rings can
come off after sawing by lifting them slightly. They just slide
down the sawblade and remain in a stack at the end of the blade as
my sawing progresses. As the sawing progresses through a few rings
to near the end of the slit, I merely use one finger to lift the
sawn rings off of the mandrel and on to the blade to make more room
for the saw to progress.

Sorry, I don’t have a web site for now where I can post a photo. If
anyone wants to reply off-Orchid, I can send a photo by e-mail.

Howard Woods Where it’s still too dark in the morning to see the
foothills in Eagle Idaho

Want jump ring mandrels made of hardened spring steel and already
slit long wise ? Need the jump ring mandrels in fractional inch sizes
and in millimeter sizes ? Buy roll pin or spring pins up to three /
75 mm. long at a good hardware store . These roll pins are hardened so
cut them with an abrasive mizzy or cut off wheel . These look like a C
on end view. These are made by the gazillions. Cheep…

I am enclosing an link for perhaps the best industrial supply site
available. I would highly recommend book marking this site.