Our goal is to keep as much heat in the chamber as possible. Keeping your electrical bill low and production high.
We use a different type of relay than most other furnace manufacturers. Our SCR relay and controller package eases the power to the elements rather than the hard on/off of a standard SSR. It is like a dimmer switch compared to a standard light switch. The same life extension applies to the filament in that light bulb. The vibrations of AC current and the power hitting the element has a lot to do with how long your elements will run. In our experience we have seen almost double the element life as compared to mechanical, mercury or solid state relays.
This furnace is a "wire melter", it uses A1-Kanthal elements.
The furnace is run by a Fuji controller,and an SCR package from Watlow and pulls 32 amps with the high temperature "S type" thermocouple.
It holds an easily replaceable freestanding 80 lb crucible. (not included ordered direct from Guadalupe Glass: http://stores.guadalupeglass.com/14-round-bottom-crucible-crb1002/ )
The outer dimensions of the furnace are 30" x 30" x 24" tall.
The frame is 1 1/2 welded angle iron with aluminum diamond plate on all sides except the back and bottom, which are 14 gauge steel.
The bottom of the furnace is 4 1/2 inches of 2600 brick and then 2 inches of high temp castable.
The chamber wall is 3 inch brick and grooved for the elements.
There are 3 inches of packed frac in the sidewalls for insulation which is equal to about 5" of brick in insulating quality. This keeps the outside relatively cool to the touch. Not just a brick ring with a case around it. We keep the heat in the box,
The Lid is 8 inches of high temp frax for great insulation qualities.
It Comes with the counterweight, pulleys, cable and wall hook.
Foot operated, air driven auto door opener is available for $700
Being a wire melter you will get about 1 year or more out of these elements with continuous use when using cullet. THAT IS What i suggest you use in this furnace, using "batch" will shorten the life of the elements by half or more. I suggest an element and heat ring change at least yearly. I am not responsible for early element failure, that is just part of the joys/trials of glassblowing.
The wire melter is the reason your power bill will be much lower than a sic/molly melter. This furnace costs me about $65 a month to run 24/7/365 at 7 cents a kw hour at 2100 degrees. Replacing The elements are easy and cheap, $175 to replace the elements, and $40 for the heat ring.
Be sure to check out our 80lb Crucible Pots and order direct from Guadalupe prior to the arrival of your furnace.