Float Glass firing

[the glass kid]

Can anybody help me with a  firing schedule  for a  1/4in or 6mmm piece of Float glass  12in X12in or300X300 as I dont know the coe .I have read it has to be fired a bit hotter then coe 96, please help

[Chichille8]

Use the same schedule as COE96, with a different holding time at the fusion segment. It should be more for a smaller COE, or less for a higher COE.

As you don’t know, probability for a smaller COE is, so I would go with more HOLD time.

[Stephen Richard]

CoE is a blind alley.  Not all glass labled CoE 96 will behave as described in relation to one labled 83.  There are some glasses labled 94 that behave more like float glass.  Do not equate the expansion characteristics of glass in the 0-300C temperature range with the characteriastics of glass several times hotter.  There is not a linear relationship.

If you use 790C (approximate full fusing point of Spectrum 96) you will be soaking for a very long time and getting a lot of devitrification.  You should be aiming to get your work done in about 10 minutes at the top temperature in fusing.

Fusing of Pilkington float glass for me is done at 835C for 15minutes.  Annealing is not done at 515 as for S96, but at 540 or 550C for half an hour.  Temperature reduction over the first 55C at 80C per hour, over the next 55C at 160C per hour.

Stephen Richard

blogs at: http://www.verrier-glass.blogspot.com/ and  http://www.glasstips.blogspot.com/

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