At 01:11 PM 11/12/99 -0700, you wrote:
>The combustion furnace for our Europa-SL unit just died (the third one
>to have done so). I am trying to rebuild it myself rather than buy a new
>one. Has anyone done this before? I would particularly appreciate your
>help in locating a supplier for the heating element. It is a 1 inch
>(inner diameter) X 8 inches long ceramic tube with the heating wire
>wound around it. the heating element operates at 55V AC, @ 9.1 Amps
>(that rates it at 500 W).

Rebuilding an oven is relatively simple. Wind nichrome wire (Omega,
NI80-015) around the tube, as tightly as possible without having the coils
touch, and with consistent spacing. Clamp the ends to keep the coils tight
(they will expand if released). Don't be afraid to scrap what you have and
start again if the coils aren't good enough. You can then measure the
resistance for that length to determine the current draw and wattage.

While the wire is still clamped, pot the whole thing with a powdered
ceramic. I use OmegaBond 600 from Omega. Once the ceramic has set and cured
you can release the clamps and install the element.

You will want at least an inch of nichrome wire sticking out to crimp your
leads on to. Double up the nichrome wire that does stick out (drops the
resistance to prevent burnouts in the unpotted section) and thread through
ceramic beads.

Feel free to contact me directly if you would like more information.


Paul Eby

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School of Earth and Ocean Science
University of Victoria

phone: 250-721-6183
fax:   250-472-4620