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Drop Ring Basics

This is part two of a two part tip on firing the drop ring.  Click here to go to part one.

  • Now you're ready to fire.  The heating portion of the firing is similar to many other firings.  Just fire no faster than around 500F per hour until the temperature reaches around 1250F.  You can go as high as 1350F if you wish, but realize that higher temperatures mean faster slumps and less control.  Also, different brands of glass (and even different colors!) will slump at different temperatures.  As a general rule, System 96 glass slumps at a slightly lower temperature than Bullseye glass, and window (or float) glass slumps at a higher temperature.   But you may need to experiment a bit to find the temperature that works best for your glass and your kiln.
  • Now comes the fun part.  Maintain your kiln's temperature so that the heat can do its magic.  As the glass soaks, you'll first notice a small bulge of glass poking through the hole in the ring.  As the glass continues to soak, more and more of the glass will poke through.  Keep a careful eye on the glass as it droops.
  • It may take as much as half an hour for the glass to droop far enough to touch the kiln shelf below. Once it touches, you will need to continue to monitor the glass until the base takes on the desired shape. Be careful not to over fire or the base of the glass will distort unacceptably.
  • Once you are happy with the appearance of the piece, flash vent to stop the slumping and then anneal and cool as normal.  (Flash vent means to carefully open the door or lid of your kiln to allow some heat to escape.  Allow the kiln to cool below 1100F.)  Remember to adjust your annealing schedule if your piece has more layers of glass than in your typical firing.

This kind of slump is fairly simple, but many people find the "top hat" shape appealing.  It can be varied in several ways, but it's the foundation to more complicated shapes and drop ring techniques. 

Click here to go to the next part of this tip, which explains how to tack fuse and slump through a drop ring at the same time.


Copyright 2005 Brad Walker.  All rights reserved.

Parts of this discussion have been previously published in Glass Craftsman magazine.  More advanced drop ring techniques, such as tack fusing and slumping in one firing, making custom drop rings, and creating rimless vases and bowls drop rings, will be discussed in future daily tips.

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Copyright 2005-2006 by M. Bradley Walker.  All rights reserved.

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