Friday, December 21, 2007

Tools Of The Trade Part 3 - Meet The Mandrels

It's time to meet the beadmakers friend, the mandrels.  No, I'm not referring to Barbara Mandrel and her sisters from the 70's TV show, but to the steel rods used when making beads.

"How do you get the holes into beads?  Do you drill them out?"

If only had a $1 every time someone asked me this question.  Time to demystify how the holes get into the beads.

While I suppose the glass could be drilled out, that would introduce stress back into the glass and could result in a lot of wasted beads.  The simplest way to the holes into the glass is to make the bead with the hole right there from the start.  Here's where the mandrels come into play.  

As you can see from the picture, the beads are created around the steel rod, so that when the rod is removed, a hole in each bead is already present.  The grayish-white stuff on the mandrels in the picture is called Bead Release, which is a liquid clay-like substance that each rod is dipped into and allowed to dry before the mandrel can be used in the torch.  

If the release is not fully dry before glass is applied, bubbles in the glass can form from the steam leaving the bead release and ruin the bead.  Without having the bead release on the mandrel, the bead would not come off after annealing.

Mandrels come in various sizes from over 1 inch thick (for very large holed beads), down to 1/16th of an inch for very tiny holes.  For beads that require marvering (shaping), I find the 1/16th mandrels are a bit too thin which is why bicones usually have a 3/32nd mandrel hole or larger.

Once the beads come off the mandrels, the bead release inside the beads must be removed.  Since the glass is wrapped onto the mandrels hot, the bead release sticks to the glass.  I use a specially design diamond drill bit to remove bead release and clean the holes so that there is not any release left inside.  

This is especially important for beads made with transparent colors where you can see the hole.

As always, if you have any questions or want to suggest topics, please do not hesitate to contact me either through this blog or on my web site or Etsy store at:

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