Comparison Of Slow & Fast Cooled Iron Reds.

[Pres]

I guess I am one of the really oldies here. I fire without a kiln setter or a computer controlled system of any kind. It was a strange order for L&L back in the day, and they did not want to sell one that way, but after explaining what I wanted they made the kiln. The reason for this is that I wanted to be able to fire down or hold at a temperature for a little longer. In the end, It is a pain to babysit, but I can do any of the ramping up or down I need. Only problem is being certain of temp. I have gotten pretty good at checking this by kiln color. These days, if I buy a new kiln, it will have the whole nine yards!

[Bob Coyle]

I'm not so sure how you would calculate heat work. Even with a computer controlled kiln there is a lot of slop. I measured the voltage difference on three K thermocouples I have and they varied by as much as 75 F at around 2100 F. small changes in placement of the thermocouple and kiln loading also make a big difference. I always watch the cones.

 

I don't think one persons ramp can be reproduced very closely from one kiln to another. From what I found, reproducibility is the important thing. Once you have a good ramp that works with your glazes... stick with it and don't mess with anything. Even then your thermocouple will drift as it ages and your ramp will change over time.

[John255]

I guess I am one of the really oldies here. I fire without a kiln setter or a computer controlled system of any kind. It was a strange order for L&L back in the day, and they did not want to sell one that way, but after explaining what I wanted they made the kiln. The reason for this is that I wanted to be able to fire down or hold at a temperature for a little longer. In the end, It is a pain to babysit, but I can do any of the ramping up or down I need. Only problem is being certain of temp. I have gotten pretty good at checking this by kiln color. These days, if I buy a new kiln, it will have the whole nine yards!

 

 

Pres,

I too know all about kiln baby-sitting. I've probably spent more time on my knees watching cones than the new Pope spent praying.

I was just about to get serious with this guy who is selling a computer control kit for kilns for about $250 when a computer test kiln came available here for $300.

You may be interested:

http://www.ebay.com/itm/Plug-Play-PID-Programmable-Ramp-Soak-Temperature-Controller-Kiln-Pottery-Glass-/111040589662?hash=item19da88ef5e

Regards,

John255

[John255]

I'm not so sure how you would calculate heat work. Even with a computer controlled kiln there is a lot of slop. I measured the voltage difference on three K thermocouples I have and they varied by as much as 75 F at around 2100 F. small changes in placement of the thermocouple and kiln loading also make a big difference. I always watch the cones.

 

I don't think one persons ramp can be reproduced very closely from one kiln to another. From what I found, reproducibility is the important thing. Once you have a good ramp that works with your glazes... stick with it and don't mess with anything. Even then your thermocouple will drift as it ages and your ramp will change over time.

 

 

Bob,

Very fine post.

Glad to have your data on thermocouples.

I've been concerned about that, and don't trust them.

I still watch for the beginning of the cone bend at 100/hr.F to start the soak while observing the tip just touching to start the first down ramp.

Completely agree we should not rave about our ramps.

Regards,

John255

[Pres]

I guess I am one of the really oldies here. I fire without a kiln setter or a computer controlled system of any kind. It was a strange order for L&L back in the day, and they did not want to sell one that way, but after explaining what I wanted they made the kiln. The reason for this is that I wanted to be able to fire down or hold at a temperature for a little longer. In the end, It is a pain to babysit, but I can do any of the ramping up or down I need. Only problem is being certain of temp. I have gotten pretty good at checking this by kiln color. These days, if I buy a new kiln, it will have the whole nine yards!

 

 

Pres,

I too know all about kiln baby-sitting. I've probably spent more time on my knees watching cones than the new Pope spent praying.

I was just about to get serious with this guy who is selling a computer control kit for kilns for about $250 when a computer test kiln came available here for $300.

You may be interested:

http://www.ebay.com/...=item19da88ef5e

Regards,

John255

 

 

Link to the plug and play controller was for 15 amp. My Land L is 78 amp. Don't see compatibility there. Thanks for the link, and if I find one I can wire into the line and then put thermocouple in the kiln, I might. . . . think hard about it. Heck my L&L is only 30 years old.

[Bob Coyle]

I'm not so sure how you would calculate heat work. Even with a computer controlled kiln there is a lot of slop. I measured the voltage difference on three K thermocouples I have and they varied by as much as 75 F at around 2100 F. small changes in placement of the thermocouple and kiln loading also make a big difference. I always watch the cones.

 

I don't think one persons ramp can be reproduced very closely from one kiln to another. From what I found, reproducibility is the important thing. Once you have a good ramp that works with your glazes... stick with it and don't mess with anything. Even then your thermocouple will drift as it ages and your ramp will change over time.

 

 

Bob,

Very fine post.

Glad to have your data on thermocouples.

I've been concerned about that, and don't trust them.

I still watch for the beginning of the cone bend at 100/hr.F to start the soak while observing the tip just touching to start the first down ramp.

Completely agree we should not rave about our ramps.

Regards,

John255

 

 

Yes, I don't pay much attention to the actual top temperature recorded. Two sets of witness cones, one high, one low tells the tale. I watch the ramp till it is close, and then watch the cones.

 

I have a small test kiln with a kiln sitter and find running the same ramp resulted in top temperatures that differ by 50- 75 F when the sitter shuts off... And that is with the thermocouple measured to be the same distance from the wall . If I push it in an inch further, the setter drops almost 100 F lower than it reads an inch closer.