Element Coil Stretching

New replacement elements for Glass Hive lampworking kilns come as a tight coil. Stretch them to their installed length before fitting them in the kiln's brick grooves.

⬇ Download the printable PDF

Unplug the kiln before removing or installing an element.

Tools

  • Tape measure
  • Bench vise
  • Locking pliers
  • Safety glasses: an element can slip from the vise or the pliers mid-pull. Keep them on for the whole stretch.

How to stretch an element

Stretching is trial and error: plan to pull the element more than once before it lands at the right length. A long benchtop vise lets one person work alone; otherwise, work in pairs.

  1. Measure and mark the element's installed length (see the table below), starting from the end that will stay fixed in the kiln.
  2. Clamp the fixed end firmly in the bench vise.
  3. Using the locking pliers, pull the element 10% beyond the installed length, then note exactly where you stopped.
  4. Release the pull and let the element relax fully. It will almost always spring back short of the installed length on the first try.
  5. Stretch again, this time pulling slightly beyond your first mark. Mark the new stopping point.
  6. Repeat the pull-and-relax cycle. Each round narrows down exactly how far you need to pull to land on the installed length once the element relaxes.

Correcting an overstretched element

If it's… Do this
Slightly over With the fixed end still clamped, loosely shake the element. The coil's memory effect will usually pull it back to length on its own.
Well over Shaking won't be enough: compress and re-stretch the element instead. If it won't compress evenly, run a rod down the coil's interior to close it up without over-distorting the turns.
Never cut an element short to fit. Removing coil turns makes the element draw more amperage and run hotter. Best case, that shortens its working life. Worst case, it starts a fire. If it's too long, stretch it correctly – don't trim it.

Stretch lengths by kiln

Stretch each element to this length. Kilns with two elements: stretch both to the length shown.

Kiln Stretch length (120v and 240v)
Short Guy 41" (wall element) · 30" (roof element)
Short Deep Guy 52"
Short Deep & Tall Guy 54"
Regular Guy 62" (wall element) · 33" (roof element)
Regular Tall Guy 60" (2 elements)
Regular Deep Guy 76"
Regular Deep & Tall Guy 79" (2 elements)
Medium Guy 71"
Medium Tall Guy 70½" (2 elements)
Wide Guy 79"

Not sure which kiln you have, or your kiln isn't listed? Call 541-961-6978 before stretching.

Need a new element? Shop replacement elements and parts.

⬇ Download the printable PDF

Questions? We're happy to walk you through it.
Call 541-961-6978 or email glasshivekilns@gmail.com. Every kiln and furnace is built to order by our family in Oregon.

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