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Post by jfox on Nov 21, 2015 10:38:02 GMT -6
I have gotten a lot of good deals on craigslist last year i posted a pic of a 100 cuft downdraft i got for free (It's still sitting under tarps) this time i violated my 0 dollar price point and spent $300. this is a Quartz annealing oven with a perfect 2400 degree lining the thing that sucked me in is the 18 huge Globar heating elements (silicon carbide).this kiln was made in 1995 but i talked to the manufacturer they still make these and its only $48000. I may try to sell it high or i was thinking of adding a zirconia fiber lining those globars can go to at least 1600 C sorry still having trouble with pictures try these, perhaps the moderator can fix the links   plus.google.com/+jfoxvideo1/posts/eMTAfPaLUPMplus.google.com/+jfoxvideo1/posts/9Sfnw6ZSAzt |
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Post by tileman2 on Nov 21, 2015 17:18:28 GMT -6
Jim:
Have read somewhat about enclosed silicon carbide elements- they last almost a lifetime from what I understand. You should be able to punish this kiln by firing minerals and chemicals that would eat ordinary APM's alive. Enjoy the ride- have fun with it.
Tom
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Post by jfox on Nov 21, 2015 20:16:15 GMT -6
Tom yes they can last forever if you dont mess with them they are fragile but they can operate at high temp and other atmospheres, not as good as Molybdenum disilicide . I need an auxiliary generator to run that thing it wants 200 amps
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Post by tileman2 on Nov 22, 2015 17:34:26 GMT -6
Jim:
Would love to see close ups of the controllers. I do not recognize the design- obviously an industrial application. OSHA requires those nice big green (on) and off (red) buttons. The fact there are two different input pads is also interesting.
Tom
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Post by jfox on Nov 22, 2015 18:17:44 GMT -6
thanks Greg for fixing the links i dont know what changed on my end . Tom those controllers are old hewlett packard programmable controllers one lets you set mutiple time and setpoints (its not a real ramp control)and the other a high limit control so im going add a bartlett ramp controller
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Post by tileman2 on Nov 23, 2015 20:32:35 GMT -6
Jim:
After two hours in a local bookstore, I found a chemistry book that has the information I need to fill in the formulas. "The Complete Idiots Guide to Chemistry: by Ian Guch. The equations I have known for sometime; the assignment of values has always been the problem. Turns out it was right under my nose: every element has a standard molar entropy assigned which are the base lines for the formula. Then the variables such as fluxes or acids; then the final calculations of heat. Will have to make a change however in the application of heat: converting temperature into free energy. At least I have numbers to give my trig buddy- will see where it goes. For the time being I am going to give Frit a neutral value of 0: because the equilibrium should be constant upon cooling. So the only variables would be ZNO, SiO2, and fluxes.Not sure what to do with the colorants: or if I should even include them because Zinc-silicate is the final product.
Tom
Tom
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Post by jfox on Nov 24, 2015 5:23:30 GMT -6
The Complete Idiots Guide to Chemistry sounds like a book we should both own
I dont know why your confused its all so clear
If a mole of substance were at 0 K, then warmed by its surroundings to 298 K, its total molar entropy would be the addition of all N individual contributions:
S^\circ = \sum_{k=1}^N \Delta S_k =\sum_{k=1}^N \int \frac{dq_k}{T} \, dT
you cant negate the frit because it enters into the reaction its crystal structure changes
make sure you dont confuse your helmholtz free energy with your Gibbs free energy or your entropy with your enthalpy temerature is not equivilent to free energy its more related to the change of temperature or thermodynamic "work" I can remember failing a test in chemistry in this area
I respectfully submit you are building another house of cards
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Post by tileman2 on Nov 24, 2015 17:36:41 GMT -6
Jim:
Actually it is a house of cardboard- built a house of cards in the old forum. The frit will remain O value because the top chemists in the world still do not know how to classify it. Maybe I should come out to CA and help you rebuild these kilns instead: have rebuilt a few already. Have always believed there is a way to calculate formulation without the endless testing. By the way- I do not mean calculation as in a glaze calculator- already own one. Lastly, just when I declare I will never buy a wheel- picked one up at an estate sale for $100. The lady also had two old Duncan kilns that would cost more to move than they wanted for them. Going Saturday to another sale: the seller claims they have several bags of Pemco 283.
Tom
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Post by jfox on Nov 25, 2015 8:20:37 GMT -6
I think you will enjoy the wheel Tom they can be frustrating but occasionally make you very happy (like a women, well not quite)
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