Venting a kiln yourself

[nafeeza]

Hi Guys,

I have a small test kiln from paragon that has one peep hole and no vent. Everyone that I have contacted says that small test kilns don't need to be vented, just prop the lid open for the first few hours of firing and then close it. I have not had any success with this. I tried keeping it propped open until it reaches 1400 degrees, however it never reaches that temperature probably because the heat is escaping. 

It's mainly affecting my red glazes right now, however all of my glazes come out very dark and the red ones look burnt and brown ALL the time. After doing a lot of research, I can only guess that its because there isn't proper ventilation happening inside of the kiln.

Is there a way that I can vent the kiln myself? I can't really afford an actual venting system right now, and I don't even know if those would work on my kiln because it's so small. Does anyone have any recommendations?

[neilestrick]

How small is the kiln- what model? No need to keep it propped that long. Close it up at 1000F at the latest, but leave the peep open. How hot are you firing?

[Bill Kielb]

2 hours ago, nafeeza said:

Hi Guys,

I have a small test kiln from paragon that has one peep hole and no vent. Everyone that I have contacted says that small test kilns don't need to be vented, just prop the lid open for the first few hours of firing and then close it. I have not had any success with this. I tried keeping it propped open until it reaches 1400 degrees, however it never reaches that temperature probably because the heat is escaping. 

It's mainly affecting my red glazes right now, however all of my glazes come out very dark and the red ones look burnt and brown ALL the time. After doing a lot of research, I can only guess that its because there isn't proper ventilation happening inside of the kiln.

Is there a way that I can vent the kiln myself? I can't really afford an actual venting system right now, and I don't even know if those would work on my kiln because it's so small. Does anyone have any recommendations?

I’m with Neil, dark glazes? What are you firing to, what schedule, how long does it take, do you use witness cones and what cone ........ glazes can be darker for several reasons. Propping the lid early on should be reasonable  so I am not sold on the not enough oxygen theory. I would look at other aspects of this to be sure. Often small kilns can go really  fast compared to larger ones. They are smaller and reds can flash on other pots, how tightly is this packed.

[nafeeza]

2 hours ago, neilestrick said:

How small is the kiln- what model? No need to keep it propped that long. Close it up at 1000F at the latest, but leave the peep open. How hot are you firing?

It’s the paragon xpress 1193.  I found a firing schedule from another group and have been using that. The highest temp in the firing schedule is 2185 degrees however I used a witness cone 6 and my kiln doesn’t reach that temperature. There’s always a “failed to fire message”. 

[nafeeza]

1 hour ago, Bill Kielb said:

I’m with Neil, dark glazes? What are you firing to, what schedule, how long does it take, do you use witness cones and what cone ........ glazes can be darker for several reasons. Propping the lid early on should be reasonable  so I am not sold on the not enough oxygen theory. I would look at other aspects of this to be sure. Often small kilns can go really  fast compared to larger ones. They are smaller and reds can flash on other pots, how tightly is this packed.

It’s not packed too tightly because I’m using test tiles until I can get the glazes to come out correct. I did use witness cones in my last few firings and my kiln is not teaching cone 6.  I kept my red glazes on a separate shelf from the blues so I don’t think they would’ve flashed. 

[neilestrick]

I had a little Paragon test kiln similar to that one and it wouldn't reach temperature unless I ran a program where it was set at 100F/hr for the last 400 degrees, even with brand new elements. It just didn't have the power to keep up with any of the regular programs. I'm thinking yours definitely can't keep up with the 350/hr rate to 2000F. Try doing a much slower program, like 250F/hr to 1800, then 100F/hr to 2232F if you're trying to get to cone 6.

[nafeeza]

33 minutes ago, neilestrick said:

I had a little Paragon test kiln similar to that one and it wouldn't reach temperature unless I ran a program where it was set at 100F/hr for the last 400 degrees, even with brand new elements. It just didn't have the power to keep up with any of the regular programs. I'm thinking yours definitely can't keep up with the 350/hr rate to 2000F. Try doing a much slower program, like 250F/hr to 1800, then 100F/hr to 2232F if you're trying to get to cone 6.

Okay thanks! I’ll try it. Do you think that’s why my colors aren’t coming out as bright as they should be? 

[neilestrick]

2 hours ago, nafeeza said:

Okay thanks! I’ll try it. Do you think that’s why my colors aren’t coming out as bright as they should be? 

It could just be a case of the kiln not reaching temp, or because those little kilns cool too quickly. Let's get it up to temp first, then we can figure out the color issues. Which reds are you using?

[nafeeza]

54 minutes ago, neilestrick said:

It could just be a case of the kiln not reaching temp, or because those little kilns cool too quickly. Let's get it up to temp first, then we can figure out the color issues. Which reds are you using?

Potters choice chun plum and Smokey merlot. I’m going to glaze tomorrow and let you know how it goes! Thanks for your advice :)

[neilestrick]

11 minutes ago, nafeeza said:

Potters choice chun plum and Smokey merlot. I’m going to glaze tomorrow and let you know how it goes! Thanks for your advice

Fingers crossed!

[Bill Kielb]

2 hours ago, nafeeza said:

Potters choice chun plum and Smokey merlot. I’m going to glaze tomorrow and let you know how it goes! Thanks for your advice

This might be your manual, if so the schedules are on pages 13 and 14. Definitely try a medium cone fire instead of your own. I didn’t read entirely through this but if you got a fail message I believe they point to a thermocouple error which means check the connections and thermocouple itself. You could also have a fired too long message which is quite different and aligns with your description of the firing.

https://www.paragonweb.com/files/manuals/IM222_Sentryxpress_ConeFr_Ramphd.pdf

[neilestrick]

3 minutes ago, Bill Kielb said:

This might be your manual, if so the schedules are on pages 13 and 14. Definitely try a medium cone fire instead of your own. I didn’t read entirely through this but if you got a fail message I believe they point to a thermocouple error which means check the connections and thermocouple itself.

https://www.paragonweb.com/files/manuals/IM222_Sentryxpress_ConeFr_Ramphd.pdf

I assumed it was the FTH (failed to heat) error code.  @nafeeza did you get FAIL, or FTH (failed to heat), or FTL (firing too long) error code? Always a good idea to check the thermocouple connections, though.

[nafeeza]

9 hours ago, Bill Kielb said:

This might be your manual, if so the schedules are on pages 13 and 14. Definitely try a medium cone fire instead of your own. I didn’t read entirely through this but if you got a fail message I believe they point to a thermocouple error which means check the connections and thermocouple itself. You could also have a fired too long message which is quite different and aligns with your description of the firing.

https://www.paragonweb.com/files/manuals/IM222_Sentryxpress_ConeFr_Ramphd.pdf

Thanks for sending that. That is the manual I have but I never thought to check for a firing schedule. & the schedule matches up with the advice from @neilestrick    
 

i am getting a failed to fire message. Which is why I assumed my kiln wasn’t reaching the correct temperature from being propped opened. I thought it was adding to the programmed time because heat was escaping. 

[Sorcery]

Those glazes will be brown of thin.

8/10 beginners use them to thin.

Chun Plum was a runner for me.

Best.

Sorce

[Bill Kielb]

6 hours ago, nafeeza said:

Thanks for sending that. That is the manual I have but I never thought to check for a firing schedule. & the schedule matches up with the advice from @neilestrick    
 

i am getting a failed to fire message. Which is why I assumed my kiln wasn’t reaching the correct temperature from being propped opened. I thought it was adding to the programmed time because heat was escaping. 

Sounds like we are all saying the same thing so just to be sure, you are currently getting an FTL error (Fired Too Long) and this firing you will run the preprogrammed (built in) firing schedule and only keep the lid propped slightly open for a short period of time at the very beginning of the firing to let the moisture out as your glazes may  continue to dry. Definitely close it by 1000 degrees or sooner, I doubt  you need it open any longer than the first hour of your firing, two hours max.

Sound about right?

 

[nafeeza]

1 hour ago, Bill Kielb said:

Sounds like we are all saying the same thing so just to be sure, you are currently getting an FTL error (Fired Too Long) and this firing you will run the preprogrammed (built in) firing schedule and only keep the lid propped slightly open for a short period of time at the very beginning of the firing to let the moisture out as your glazes may  continue to dry. Definitely close it by 1000 degrees or sooner, I doubt  you need it open any longer than the first hour of your firing, two hours max.

Sound about right?

 

Yup! I closed it at the 2 hour mark and took the peephole out. It was at around 700 degrees when I closed it 

[Bill Kielb]

10 minutes ago, nafeeza said:

Yup! I closed it at the 2 hour mark and took the peephole out. It was at around 700 degrees when I closed it 

Probably no need to keep the peephole out actually. Only wasting energy.

[nafeeza]

Okay guys. @neilestrick @Bill Kielb So this morning I went and got the test piece from the kiln. There was an error message again that said FTL. I had turned the kiln on at about 12:30pm and checked on it periodically. The last time I checked on the kiln last night was 11pm and it was at 2077 degrees.  I figured it was reaching the correct temperatures so I left it alone after that.
 

However, The glaze piece that I did came out pretty great! 
 

I tested a pot that broke in a bisque fire so that’s why it’s shaped like that. The one on the right is an example of how all of my glazes have been coming out. They both have the same glazes on them. 

[Bill Kielb]

12 minutes ago, nafeeza said:

Okay guys. @neilestrick @Bill Kielb So this morning I went and got the test piece from the kiln. There was an error message again that said FTL. I had turned the kiln on at about 12:30pm and checked on it periodically. The last time I checked on the kiln last night was 11pm and it was at 2077 degrees.  I figured it was reaching the correct temperatures so I left it alone after that.
 

However, The glaze piece that I did came out pretty great! 
 

I tested a pot that broke in a bisque fire so that’s why it’s shaped like that. The one on the right is an example of how all of my glazes have been coming out. They both have the same glazes on them. 

Well at least you got closer to cone 5/6.   That error means your kiln is taking too long. So just curious if you left the peep out, but even if you did it still likely should have made it so we are left with not all elements are working which could be a relay or element and / or the elements have many firings on them and they are simply worn to the point where they need replacement.

How many firings do you have on those elements and do you know if they all begin glowing red?

[nafeeza]

44 minutes ago, Bill Kielb said:

Well at least you got closer to cone 5/6.   That error means your kiln is taking too long. So just curious if you left the peep out, but even if you did it still likely should have made it so we are left with not all elements are working which could be a relay or element and / or the elements have many firings on them and they are simply worn to the point where they need replacement.

How many firings do you have on those elements and do you know if they all begin glowing red?

I don’t feel like I have used the kiln that often for it to be worn, but I did have it a few years before actually using it. I’d say I probably have around 20 firings on this kiln. 
 

I don’t know if all the elements have been glowing red. I did read that if I turned my kiln on and left the top open I could check it that way. So today I’ll try that. 

[nafeeza]

@Bill Kielb oh and I did put the peephole back in! It probably went an hour without the peephole 

[Stephen]

I have have never ever left my lid propped at all on my 12"x 14" un-vented test kiln. I just leave the 1st peep out until about a 1000 and plug it. Propping the lid just seems absurd on a little kiln like that. I have used it that way for 10 years and never seen an issue and it fires exactly like the 7 and 9cf kilns. 

edit: it runs on a Bartlett electronic controller usually slow bisque to 04 and slow glaze to cone 5 with 20 minute soak. As I said it has no trouble duplicating the larger kiln. The only difference is that all of them ramp down as they cool to 1200 and then cools on its own and the little will cool below 100 degrees F faster that the larger ones by a couple of hours but that's it.

[neilestrick]

@nafeeza which firing schedule did you use?

[Bill Kielb]

1 hour ago, Stephen said:

I have have never ever left my lid propped at all on my 12"x 14" un-vented test kiln. I just leave the 1st peep out until about a 1000 and plug it. Propping the lid just seems absurd on a little kiln like that. I have used it that way for 10 years and never seen an issue and it fires exactly like the 7 and 9cf kilns. 

edit: it runs on a Bartlett electronic controller usually slow bisque to 04 and slow glaze to cone 5 with 20 minute soak. As I said it has no trouble duplicating the larger kiln. The only difference is that all of them ramp down as they cool to 1200 and then cools on its own and the little will cool below 100 degrees F faster that the larger ones by a couple of hours but that's it.

The error she is getting is it slows down to less than 27 degrees per hour and her firing time is excessive so at this point she needs to make sure all the elements are working.  For a glaze fire I agree, leave the peep out or prop it for a bit but really, not a bunch of water to burn off. Usually only wastes energy IMO. Most electric kilns are plenty leaky so oxidation is usually not an issue.

[nafeeza]

1 hour ago, neilestrick said:

@nafeeza which firing schedule did you use?

I used the preprogrammed schedule for cone 5 on medium.