kiln controllers

[Ian]

HI
My name is Ian and I live in South Africa. I am new at warm glass work and I need some help I have a large coffin shaped kiln with top and side elements and a Ipco Studio 3000 10 programme controller.
It has the following firing cycle
1 A delay time in hrs and min
2 up ramp rate in x degrees per hour
3 The ramp end temp
4 up ramp rate in x degrees per hour
5 a soak temp
6 a soak time
7 down ramp rate in degrees per hour
Because there is only the one down ramp rate in degrees per hour to a set temp for switch off I am worried about annealing
I will be working only with float. could anybody please help me with converting a firing cycle so that I can anneal properly. As an example how would I set the annealing for 4mm float with 3mm appliques with enamel powder in between the glass
Thank you very much for your help
Ian

[Bert Weiss]

HI
My name is Ian and I live in South Africa. I am new at warm glass work and I need some help I have a large coffin shaped kiln with top and side elements and a Ipco Studio 3000 10 programme controller.
It has the following firing cycle
1 A delay time in hrs and min
2 up ramp rate in x degrees per hour
3 The ramp end temp
4 up ramp rate in x degrees per hour
5 a soak temp
6 a soak time
7 down ramp rate in degrees per hour
Because there is only the one down ramp rate in degrees per hour to a set temp for switch off I am worried about annealing
I will be working only with float. could anybody please help me with converting a firing cycle so that I can anneal properly. As an example how would I set the annealing for 4mm float with 3mm appliques with enamel powder in between the glass
Thank you very much for your help
Ian

Ian

My schedule for 1/2" goes like this: Soak at 1000 for 2 hours. Take 2 hours to go down to 900. Take 1.5 hours to go to 700. Take 1.5 hours to go to 300. The most important steps are to soak at 1000 and ramp down to 900 then 700. I'm not sure if you can get the soak to happen. If not, you need to set a slow ramp that will get you from, say 1050 down to 700. Maybe 25 degrees per hour or a bit slower. Then shut off. I think that will work.

I know of 3 tests to tell if your annealing is good. First is the polarized light test on clear glass. IF the halos turn blue, you have a lot of stress. Next is my favorite, the dishwasher test. Make a piece that fits in a dishwasher and give it a cleaning. If there is stress from heating, it will pop. If if lives you are probably good to go. The third test is see how it cuts with a glass cutter. In order to cut well glass needs some stress, but not too much.

If you can make some money, perhaps you can sell your controller to a potter and buy a controller that is better suited to annealing glass.

[Ian]

HiBert
thank you for your help.
Just to see that I have it right After I have done my soak at no 6 which for a fused project which I have found to be best at 4 min at 800 degrees(1472 F)
then I should set my down ramp at no 7 from 1472 F (800C) to 700F (370C) at +- 25F (I hope I have the right formula for converting rates as being F per hour /1.8 which would give me +-14C per hour and then switch off. One good thing about my kiln is that it takes approx 7 hrs to cool from 300C to cold enough to open. Once again thank you
P.S. these kilns are supplied by our local hot glass guru as being the only kilns designed for Hot Glass Work so I am a bit upset to find that a controller that cost me nearly 4000.00 rand is not actually good enough. But i suppose it is better than a low med hot switch
best regards
Ian

[Bert Weiss]

HiBert
thank you for your help.
Just to see that I have it right After I have done my soak at no 6 which for a fused project which I have found to be best at 4 min at 800 degrees(1472 F)
then I should set my down ramp at no 7 from 1472 F (800C) to 700F (370C) at +- 25F (I hope I have the right formula for converting rates as being F per hour /1.8 which would give me +-14C per hour and then switch off. One good thing about my kiln is that it takes approx 7 hrs to cool from 300C to cold enough to open. Once again thank you
P.S. these kilns are supplied by our local hot glass guru as being the only kilns designed for Hot Glass Work so I am a bit upset to find that a controller that cost me nearly 4000.00 rand is not actually good enough. But i suppose it is better than a low med hot switch
best regards
Ian

Ian

I hope that you can ramp down quickly by opening the kiln to drop to around 1050. 25 degrees per hour is way too slow to drop from 1475.