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Old 12-06-2003, 07:01 PM
David Paterson
Posts: n/a
I have been blowing glass for over 15 years, and I built my wire melter to melt a higher quality of glass than is available in my invested pot furnace. And also occassionally to melt one or more pots of color.

So far the glass quality is amazing from such a cheap and easy to build unit.

With all the talk of 'porsches', 'hobbyists', and 'professionals', nobody has addressed one issue. The United States is involved in two oil wars at present, and the world is running out of cheap oil and gas.

To quote an article from The Guardian in the UK,

"The oil industry is buzzing. On Thursday, the government approved the development of the biggest deposit discovered in British territory for at least 10 years. Everywhere we are told that this is a "huge" find, which dispels the idea that North Sea oil is in terminal decline. You begin to recognise how serious the human predicament has become when you discover that this "huge" new field will supply the world with oil for five and a quarter days.

Every year we use four times as much oil as we find. The petroleum geologist Colin Campbell calculates that global extraction will peak before 2010. In August, the geophysicist Kenneth Deffeyes told New Scientist that he was "99% confident" that the date of maximum global production will be 2004. Even if the optimists are correct, we will be scraping the oil barrel within the lifetimes of most of those who are middle-aged today."

At least a porsche has a relatively small engine, and goes real fast because of good engineering.

My invested pot furnace, which is five years old, still gives good studio quality glass (even with a few one inch or larger cracks in the botton), melts 150 lbs of glass and runs on about 1200 litres of propane a month (about 320 US gallons). I also reheat out of the crown. My friend has a Correll pot furnace that melts about 150 lbs, used entirely for production work, and even with the heat recuperator, it gulps back close to twice as much propane. Frankly, I dont see the logic.

The reason the Correll furnace is more expensive to run is that it is perhaps double the internal volume because of the need to have a lot of space around the pot.

In reality, very few blowers need better glass quality for the bulk of their work than is available in a tank or invested pot furnace.

If you can get at least 8 monthes out of Kanthal A1, and you should shut down to replace the pot in eight monthes, and the elements are really cheap and easy to replace, and it cost HALF as much to run as a moly furnace or a Correll furnace, then I would directly challenge the logic of using these over-designed energy guzzling and EXPENSIVE units.

I am sure that one day not too far off, using thousands of gallons of propane or huge amounts of electricity just to make baubles for rich people will be simply outlawed.
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