Curious to know !

[Jan de Jong]

Hello ! Did write wrong the firing-schedule of a 37 1/2 cm (1 1/2 inch) thick piece of Spectrum96 on a note for by the kill. The good Step 4 was afap and hold 3 hrs. Now I did fire with this Step 4: 750 C. (1382 F.) to 510 C. (950 F.) and No hold. The piece was broken ! Stupid mistake of course, but what was the important mistake.... the slow cooling to 510 C. OR no hold on 510 C. ? Or both ? Jan

[Kevin Midgley]

Buy this.
Read it multiple times cover to cover before you fire glass again.
http://www.hisglassworks.com/shop/firin ... -html.html

Perhaps you should translate it into Dutch?

[Jan de Jong]

@Kevin: Thank you for your answer ! As for the book: Great, but for the few pieces I fire in a year (hobby !) I use the firing schedules from Spectrum. For the first time I did fire a 1 1/2 inch thick piece and did note the wrong things on a piece of paper to set the schedule. Stupid! So, this has happened, but I wish to learn and wonder what did occurs exactly the break and therefore this question on the forum. Jan de Jong

[Kevin Midgley]

The book provides the answers and the understanding of the behavior of glass you are asking someone on this board to explain quickly. Once you appreciate the knowledge in that book, you will understand why I have recommended it to you. I paid over 3 times the price I found it for sale at for you. It is much cheaper to buy it than waste money on expensive glass breaking perhaps a year later. A schedule provided by a glass manufacturer is only the starting point for calculating how a kiln firing should be donein your kiln as every kiln is different. The book provides you with the understanding necessary to make your firings a success. I know of no other source for this information. Do not just try and use the schedules. You must read the whole book before starting as important information is to be found on many different pages.
The book was unavailable for quite some time as the author, Graham Stone, found people were referring to just the schedules without an understanding of the whole book. In frustration he took the book off the market for a number of years.

[Jerrwel]

The book provides the answers and the understanding of the behavior of glass you are asking someone on this board to explain quickly. Once you appreciate the knowledge in that book, you will understand why I have recommended it to you. I paid over 3 times the price I found it for sale at for you. It is much cheaper to buy it than waste money on expensive glass breaking perhaps a year later. A schedule provided by a glass manufacturer is only the starting point for calculating how a kiln firing should be donein your kiln as every kiln is different. The book provides you with the understanding necessary to make your firings a success. I know of no other source for this information. Do not just try and use the schedules. You must read the whole book before starting as important information is to be found on many different pages.

What Kevin said. This is great advice to anyone who is fusing glass and does not have this book. To even start to understand what is presented in Graham Stone's book is well worth the effort; the increased understanding of glass behavior and fusing schedules may result in unexpected personal growth and maturity in fusing.

[Fiona Collins]

Hi Jan, I'd say it was the no hold that caused the problem for 1 1/2 " (37mm) I'd hold for 6 hours. 30 mins for every 3mm. Then cool from 510 to room temp really, really slowly ....

[Kevin Midgley]

Beware Jan, of taking advice on schedules without having an understanding of your kiln and set up. The formulaic schedule suggested by another contributor is not what Stone would like to have you come up with after you read and understand his book. Buy the book, read the book and see just how wrong that suggested programming formula could be for you.

[Jan de Jong]

Thank you all for your answers ! Buying Graham stone's book is perhaps not so expensive as I thought earlier (loosing glass etc.) Jan de Jong