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Old 03-20-2004, 02:46 PM
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Richard Huntrods Richard Huntrods is offline
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Re: Watt Loading for Dummies

Quote:
Originally posted by F Thumb
...though I'm still trying to talk him into squeezing 4ohms into each element for even more heating surface (Steve's afraid at that point the coils become too tight - I'm going to be the test dummy).
...
I think I can help there - I've already been the test dummy! My elements are too close together, and the life is much shorter than it should be.

My furnace was designed "on the ragged edge" w.r.t. elements. The origninal Lauchner 40lb furnace uses 8Ga. elements that look like garage door springs. 1 groove per brick, so each element is 88" long, and wired in series.

With a local element maker in my neighborhood, I chose to try smaller elements - 15Ga (not 14Ga as I've previously said).

Like the original Lauckner design, I only put 1 groove per brick, for 88" of length per element. To get the necessary wire length with the smaller guage, the coils are almost touching (stretch is about 1.5-1).

As a result, I'm only going to get a little over 1000 hours from this set of elements.

On my next element change (iminent) I plan to cut an extra set of grooves (or maybe 2), increasing the stretch to more optimum levels. I may also go to 14Ga wire. Both should extend element life significantly.

In hindsight, I should have put more grooves per brick in from the start, but we all have to learn. Besides, this process is fun, and I've gotten some awesome clear glass out of the deal.

-Richard
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