Kuba
Full Member
SztukKilka in Old Formu
Posts: 111
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Post by Kuba on Jul 18, 2015 6:45:49 GMT -6
Hello crystalline fans  Recently I am testing results small kiln vs big one. Same glaze, same schedule and of course different rate of dropping the temperature. My small 16 litres kiln is cooling down like crazy... and I thought about the idea of testing some glazes on same pots in this two kilns. Here you can see my favorite nickel combo in two firings, one in 16 liters kiln and second in 220 liters (both electric kilns, same manufacturer, same controller etc.).  P.S. This is how this glaze looks on a plate from big the kiln:  And what is really interesting, 3D crystals, I will try do do some macro photo:  If You have some similar tests please share Everybody knows that cooling rate is critical when crystals starts to grow but it is really inserting to see some field tests Have a nice day. Jakub |
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Post by tileman2 on Jul 18, 2015 8:03:39 GMT -6
1 CF = 28.31 litre 16 litre = .56 CF 220 litre = 7.77 CF
GM Kuba - morning here anyway. Hundreds of them, perhaps a topic for the Everything Else section. Will let the moderators decide that. My .25CF (7 litre) test kiln runs almost continuously to hold ramp temps because of thinner walls and little power. My 6.5CF (184 litre) and 16CF (453 litre) super dragon hold heat and run power very little to hold ramp temps. Usually there is 3 and up to 10 degrees difference to achieve similar results in the various sized kilns. Will be interested to see more of your test results> push the boundaries, do not let books tell you the limits. My new test kiln is built like my large ones, so it mimics results much better.
Tom
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Post by Koz on Jul 18, 2015 8:51:54 GMT -6
kuba,
Very consistent results from what I can see.
Your small kiln will obviously cool quicker because of the density of the load, as compared to a larger more full kiln.
If you want more control just program in a cooling rate from your top temperature.
I fire just into cone 11, then from that top temperature program in a 300 degree per hour cooling rate to my first hold at 2025 degrees.
I get the same results from my small kiln to my larger kiln that way.
You may have to adjust your top temperature down a bit to compensate for the additional heatwork with a slow controlled cool, but it will eliminate a variable and your results will be more consistent from kiln to kiln and firing to firing.
Koz
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Kuba
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SztukKilka in Old Formu
Posts: 111
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Post by Kuba on Jul 18, 2015 10:48:46 GMT -6
I on purpose do not put any controlled ramp to cool down to see the difference in firing My two kilns have USB controller and I can check how long it takes to drop temperature in big one or small one. I also find out that in smaller kiln I get better result with very quick temperature dropping - but this is hard to achieve in big kiln. The opposite way is easy to achieve (make longer cooling in small kiln) Example: from 1260 C (2300F) to 1050C (1922F) my small kiln need 14 minutes. Big one needs 40-42 minutes. What "natural" cooling times (without fixing the ramp) do you have in your kilns?  |
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Post by Arnie Benton on Jul 18, 2015 11:14:33 GMT -6
If you want the faster cooling, then you can open the lid and 'crash cool' the temperature down to where you want it - I've never done it but others have - both my kilns are in the 40 to 45 minute range.
Arnie
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Kuba
Full Member
SztukKilka in Old Formu
Posts: 111
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Post by Kuba on Jul 18, 2015 11:39:32 GMT -6
Never done crash cooling, but some day....
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Post by tileman2 on Jul 18, 2015 13:39:08 GMT -6
Arnie,
I have crashed my kiln my than my car when I was 16.. LOL
Tom
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joerg
New Member
website: www.crystalsforever.com
Posts: 49
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Post by joerg on Jul 18, 2015 14:21:46 GMT -6
Never done crash cooling, but some day.... hola Jakub! crash cooling... I did it, opening-closing the front door... in 10 min it came down from 1260 to 1090 (and an electric socket nearby almost melt :-( ), but don't like it... it reduces the flow and too many crystals stay on the pots.... like Koz... I program the downwards heat from top to holding (1 h ) ... how is your Frit 413 and 644 - project going ? hasta la vista! J |
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Kuba
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SztukKilka in Old Formu
Posts: 111
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Post by Kuba on Jul 19, 2015 1:29:11 GMT -6
I had time for only few test with 644. I need to adjust it to my stoneware. Will definitely show some results when they become interesting And thx again for those frits Joerg! |
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joerg
New Member
website: www.crystalsforever.com
Posts: 49
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Post by joerg on Jul 19, 2015 14:56:50 GMT -6
I had time for only few test with 644. I need to adjust it to my stoneware. Will definitely show some results when they become interesting And thx again for those frits Joerg! my ( and Josep Mariscal's) finding.... the 413 frit works better with porcelain, the 644 better with stoneware.... |
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Post by winner on Aug 7, 2015 18:08:19 GMT -6
Never done crash cooling, but some day.... hola Jakub! crash cooling... I did it, opening-closing the front door... in 10 min it came down from 1260 to 1090 (and an electric socket nearby almost melt :-( ), but don't like it... it reduces the flow and too many crystals stay on the pots.... like Koz... I program the downwards heat from top to holding (1 h ) ... how is your Frit 413 and 644 - project going ? hasta la vista! J crash cooling cracked my kiln lids. |
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Kuba
Full Member
SztukKilka in Old Formu
Posts: 111
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Post by Kuba on Aug 8, 2015 2:54:53 GMT -6
how badly it cracked?
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