What Should I Sit My Kiln On?

[Min]

36 minutes ago, Stephen said:

We try to time it so that that is actually around the time we wake up but if its in the middle of the night we set an alarm so that one of us gets up and goes and checks that kiln has turned off.

Slight change of subject but if you ever need to replace your controllers maybe think about the ones that have wifi with an app that goes on a tablet or smart phone. So nice to not have to get out of bed to go check the kiln! I didn't know how much I would appreciate it until I started using it, especially in the winter. (my kiln room is outside)

[neilestrick]

39 minutes ago, Stephen said:

 

Running the kilns at night I would make sure that you set an alarm to get up and check that the kiln has in fact shut down when it was expected to. We try to time it so that that is actually around the time we wake up but if its in the middle of the night we set an alarm so that one of us gets up and goes and checks that kiln has turned off. Not sure it matters if you bisque only or both bisque and glaze fire for this situation as both temps are extremely high and I don't think glaze firing is going to make any difference in the safety precautions you take. Curious to see if anyone disagrees with me on that.  

The only way to guarantee that a kiln has shut off when it was supposed to is to check it. That's true for any kiln, digital, manual, etc. So you're doing it right! 

[Stephen]

14 hours ago, Min said:

Slight change of subject but if you ever need to replace your controllers maybe think about the ones that have wifi with an app that goes on a tablet or smart phone. So nice to not have to get out of bed to go check the kiln! I didn't know how much I would appreciate it until I started using it, especially in the winter. (my kiln room is outside)

ya know I need to hook it back up but I have a small wifi camera setup that works great. It cost around $25 at Amazon I think and you can sit it on a shelve across the room and you can use the camera a thousand miles away (used it on vacation to keep eye on house and why its not in the studio right now) and pan it around the room and zoom in on stuff. I had it pointing at the kiln at one point when we went out of the house during firing and it worked great, once I saw the controller flashing complete I could relax about the firing. Thanks for the prompt need to go put it back. It is an app on my phone and is easier than having to get up. Having it build into the controller does seem cool as well. I will say it is comforting to actually see the kiln in the room firing. Obviously not necessary but just being able to visually check it out feels good.

[PeppernPatches]

On 2/17/2020 at 6:19 AM, Hulk said:

Hi PP, hope you like your 1027! I've been running my bought used thirty two year old model in the garage with a home built downdraft system for a year and a half now.

Be sure to leave a way for make up air to enter that small room. Your Envirovent will be moving a lot of air from the room. If the 1027 doesn't have holes in lid, there's that, however, might not need to drill any if there's sufficient gaps between the top section and lid, and between top section and middle section. A butane lighter flame makes a good tell-tale for air movement, or a smoke punk - to check where air is being sucked in. Likely the air flow will differ when the kiln is at temperature, vs. at ambient.

Thank you Tom! I drilled holes in the lid and I've tested it and it's drawing fine. Did the lighter test! Now my next issue is how to deal with the room getting really hot. The door opens out into another room that has a big garage door so hopefully that will be okay.

[PeppernPatches]

On 2/17/2020 at 6:19 AM, Bill Kielb said:

Since the room is mostly wood code would likely require that in the area of the kiln  5/8”  firecode drywall would likely be best.  I was a cement board proponent until I went to design a rated studio area. Hard to do with cement board, as it does not burn but unfortunately conducts the heat to what is below it better than drywall and therefore not rated in its own, cement board is a handy product though so not a bad choice, just not rated. For the floor I have seen 2” brick in the area of the kiln to two layers of cement board. I think the board would be easiest and believe it actually becomes rated the minute you install ceramic tile over it. Go figure.

Ventilation is important  in keeping the room cool and the fumes away. Fresh air in and a good exhaust out is very important and will keep the heat in the room down to within reason.  A typical kiln requires 400-600 cfm to exhaust a major portion of  the kiln heat. This is probably a window box fan on its highest setting. Please look above as well, your kiln will radiate heat, like the sun, to your ceiling quite a bit from the lid as invisible infrared energy. Just to be sure there is nothing crazy flammable above and it doesn’t get too hot above it. 
 

lots of folks run kilns in this type of environment. Common sense and regular keen observation always a good practical thing.

Thank you Bill! I am learning so much from this process. For the larger Skutt kiln, the room is small and there is no window - only a 14" X 20" W hole where an A/C unit used to reside. We've taken that out and built a galvanized sheet metal box that the Skutt Envirovent air duct will connect to and exhaust out.  The Envirovent blower is only 140cfm. There should be enough fresh air in, but I'm concerned about heat getting out. And rising.  Should I add another in-line fan next to the air duct to pull more of the warm room air out?

[PeppernPatches]

On 2/17/2020 at 11:39 AM, Stephen said:

 

Running the kilns at night I would make sure that you set an alarm to get up and check that the kiln has in fact shut down when it was expected to. We try to time it so that that is actually around the time we wake up but if its in the middle of the night we set an alarm so that one of us gets up and goes and checks that kiln has turned off. Not sure it matters if you bisque only or both bisque and glaze fire for this situation as both temps are extremely high and I don't think glaze firing is going to make any difference in the safety precautions you take. Curious to see if anyone disagrees with me on that.  

Thank you Stephen! Yes I do set alarms at night and am pretty diligent about that and can't sleep well when I fire anyways LOL!

[Bill Kielb]

On 2/23/2020 at 5:32 PM, PeppernPatches said:

Thank you Bill! I am learning so much from this process. For the larger Skutt kiln, the room is small and there is no window - only a 14" X 20" W hole where an A/C unit used to reside. We've taken that out and built a galvanized sheet metal box that the Skutt Envirovent air duct will connect to and exhaust out.  The Envirovent blower is only 140cfm. There should be enough fresh air in, but I'm concerned about heat getting out. And rising.  Should I add another in-line fan next to the air duct to pull more of the warm room air out?

The enviro-vent  will not remove much heat and in the end will not discharge anywhere near 140 cfm because of all the suction side restrictions it operates under.  It will probably discharge at its very very best 100 cfm so for a normal summer day, let’s say 70 degrees outside (makeup air) you will need a very approximate 300-400 CFM additional  exhaust when the kiln is at peak temperature to remove  most of the heat it is producing. Obviously if the makeup air is colder you will need less airflow.

In the end you might decide on a  hood and vent a kiln style vent which would remove much of the heat and  could discharge out your same opening. The one issue you will need to resolve is getting a source of fresh air, away from where you are currently discharging your fumes. (Usually 10’ away or greater separation required between exhaust and fresh air inlet)

So thinking about this from a distance, I might be inclined to use your existing opening (The AC sleeve) for an inlet that I can open and close with operable lovers (or even block off manually when not in use)  and run any exhausts I use (whatever they end up to be ) out a different path since they will be simple 4” or 6” round  penetrations terminating outside like a dryer discharge. 

It just takes some thinking and then pick what is easiest, most effective and economical. Knowing about how much (CFM) you will need and and understanding of the separation of discharge and fresh makeup air hopefully gives you some ideas. My idea above may not appeal to you at all, nor fit your situation.

Some example photos of ideas below of inlet louver and 6” dryer discharge.

 

 

 

[dmmartinarch]

I am in the middle of setting up my kiln.  I have a room adjacent to my art studio that has a large window and exhaust fan.  The issue I have is that there is LVT for flooring and I am concerned that the kiln will melt the floor or cause a fire.  What should I put under the kiln to protect the LVT?  The LVT is installed over concrete with a foam backer for comfort and vapor barrier.  I saw that 2 layers of  1/2" cement board was sufficient but am still worried.  Any help please?

[Bill Kielb]

12 hours ago, dmmartinarch said:

I am in the middle of setting up my kiln.  I have a room adjacent to my art studio that has a large window and exhaust fan.  The issue I have is that there is LVT for flooring and I am concerned that the kiln will melt the floor or cause a fire.  What should I put under the kiln to protect the LVT?  The LVT is installed over concrete with a foam backer for comfort and vapor barrier.  I saw that 2 layers of  1/2" cement board was sufficient but am still worried.  Any help please?

Lots of folks use cement board because it’s non combustible. Some kiln manuals will say cement block, still others will suggest on concrete. All  seem to be practical solutions with the cement board often being the easiest. If your kiln is on a stand then anything fireproof is decent. Let’s face it dropping something hot on the floor is probably the most likely thing so cement board works and is not nearly as much of a trip and fall  hazard as cement blocks. By LVT I assume laminated vinyl tile or pergo style stuff. Since concrete is beneath I suppose you could cut the LVT symmetrically around the kiln and install ceramic to the right height and use real ceramic Schluter transitions for a super custom surface beneath and very seamless transitions to the LVT. I don’t think many folks would go that far though.

[neilestrick]

12 hours ago, dmmartinarch said:

I am in the middle of setting up my kiln.  I have a room adjacent to my art studio that has a large window and exhaust fan.  The issue I have is that there is LVT for flooring and I am concerned that the kiln will melt the floor or cause a fire.  What should I put under the kiln to protect the LVT?  The LVT is installed over concrete with a foam backer for comfort and vapor barrier.  I saw that 2 layers of  1/2" cement board was sufficient but am still worried.  Any help please?

The LVT is not likely to catch fire, but it will heat up and discolor over time. I see that happening with vinyl composition tile. LVT is more sensitive to heat than VCT, though, so it may shrink or warp. Put down two layers of cement board, extending 12 inches beyond the kiln and it'll be good to go.