RE: [ATM] re: Fused Not Glued Glass

["Donald Good" <donald.good@comcast.net>]

Ellen,

I believe that a microwave oven heats by induction.  It is tuned to a
frequency to induce vibrations in the Hydrogen-Oxygen bonds in the water and
carbohydrates in food (narrow band absorption).  It also induces vibrations
in the free charges (electrons/ions) in conductors (broad band absorption)
which is why you should not use metal containers in a microwave.  Arcing,
excessive heat, and damage can occur to the microwave emitter which is not
designed to operate under those conditions.  

Glass does not absorb at this frequency, so glassware is only heated by
absorbing heat from the food or other absorbing material.  It was probably
the ions in the Epsom salts that absorbed the microwave energy and
transferred it to the glass to melt it rather than acting as a thermal
barrier.  Operating the microwave device outside its design environment
could burn it out.

Also, if you expect the glass in the mirror to melt, it is likely that the
sand would melt too.

And microwave devices of this type are on/off devices.  The temperature in a
kiln is normally controlled by slowly raising or lowering the
voltage/current (electric) or fuel flow (gas) by a thermometer device.
Microwaves would probably interfere with ordinary thermometer devices by
absorbing the microwaves directly rather than from the mirror.

Finally, microwave ovens are designed to contain the microwave energy with
no leakage because it is dangerous due to its penetrating power.

If it were as easy, safe, and less expensive as a normal kiln, you would see
microwave kilns on the market.

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