Re: [ATM] Microwave heating of glass

[Dale Eason <atmpob@yahoo.com>]

So what is your plan to do about annealing?  You will
not be able to use the microwave for that.  Once the
glass is no longer hot enough to be a microwave
receptor then the microwave will not work but the
glass will still need to be annealed.
 
I think standard annealing takes many days of slowly
reducing the temperature. 

Dale Eason

--- Ian Williams <i.r.williams@bristol.ac.uk> wrote:

> So, how does this sound for the next draft of the
> microwave powered 
> glass furnace method?:
> 
> Assumptions:
> 1) That fire-brick is a very poor absorber of
> microwave radiation.  If 
> anyone here can test this by trying to heat a mug of
> water enclosed in 
> fire-bricks I would be very grateful.
> 2) That plaster of paris/Alumina is also a poor
> absorber of microwaves 
> and is suitable for making a refractory mould for
> glass.
> 3) Suitable lab-safety is followed at all times.
> 
> Method (draft 2):
> * Purchase/reclaim a microwave oven with 'microwave
> stirrer' type of 
> magnetron, fire-bricks, glass of desired quality,
> several SiC sharpening 
> blocks, and Plaster of Paris/Alumina to make a
> mould.
> * Make a block of plaster of paris/alumina of
> dimensions 10"x10"x5" with 
> a cylindrical depression in the top surface, of
> diameter ~8" and depth 2".
> * Machine fire-bricks to make an enclosure that
> completely fills the 
> space of microwave leaving enough room inside for
> the mould and SiC 
> blocks.   Don't forget to fire-brick line the base
> of the microwave 
> underneath the mould.
> * Break up required amount of glass into pieces of
> size ???? cm^3.
> * Place microwave where, if it catches fire, the
> fire won't spread. e.g. 
> outside.
> *  Place fire-bricks, mould, broken glass and SiC
> blocks into said 
> microwave.  The SiC blocks could be:
>     a) all around the mould, thus absorbing all the
> microwaves, or,
>     b) only on the sides of the mould away from the
> magnetron, thus 
> allowing the glass to absorb microwaves directly
> too.
> * Set timer to somewhere around 15 minutes, press go
> and stand well back.
> 
> If you can spare some more criticism of these ideas,
> I would appreciate 
> your time.
> 
> Thanks again,
> Ian
> 
> 
> _______________________________________________
> ATM mailing list http://www.atmlist.net/
> 



      ____________________________________________________________________________________
Be a better friend, newshound, and 
know-it-all with Yahoo! Mobile.  Try it now.  http://mobile.yahoo.com/;_ylt=Ahu06i62sR8HDtDypao8Wcj9tAcJ 

_______________________________________________
ATM mailing list http://www.atmlist.net/