How safe is a kiln made from wood ?

[dkh2]

How safe is a kiln made from wood ?
At 120 degrees has any one heard of a kiln made from wood catch fire ?
After all a month or more of that temperature of 120 degrees + would tend to dry it out
wouldn't you think ?
Is Plywood safe to use to construct a kiln with Styrofoam on the outside of the wood ?
Any horror stories we should be made aware of ?

 

[FmGrowit]

I think once you get the hang of how much water it's going to use on a daily or weekly basis, you'll be fine. The wood will hold moisture longer than a non porous wall material, but it will absorb more moisture too, so it will take longer to adjust the Rh. I think the trick will be in determining when to add water to adjust the Rh.

At 120°, there is no danger of ignition, but the glue in the plywood might become unstable and release unwanted gases into the kiln or cause the ply's to delaminate. I'd use solid hardwood if it's available. You'd be surprised at how much good cheap wood is an old fallen down barn.

 

[dkh2]

I have some leaves that are BONE dry so I was taking them down then I thought of on post I
read elsewhere that said that Tobacco was so moisture absorbing that if you hung dry Tobacco
in the bathroom while you took a shower that it would start to go back into case so I tried it.
I hung some leaves that had dried in the bathroom then I took a shower and it's pretty humid in there now
but there still dry as a bone.
I must be bored
It's the closes row of leaves in my Avatar by the way

 

[FmGrowit]

If you live in an area that gets dew at night, you can put the leaves on a tarp and set them out over night. By morning, the leaf will be in case. Just gotta get up early enough to bring it in before the sun dries it out again.

 

[deluxestogie]

The ignition point of wood is 525ºF. Most fermenting kilns are kept below 140ºF. Even a flue-cure kiln would only be going up to 190ºF at the most. (Actually, the wood frame buildings at Phantom Ranch--at the bottom of the Grand Canyon--are periodically subjected to daytime temperatures over 120ºF.)

My small kiln is made of solid wood plank, and has on occasion been taken up to 139ºF. I don't worry about the wood. My remote digital hygrometer, mounted inside the kiln, is rated to operate up to 150ºF. Hopefully its plastic case is also rated that high. Within the kiln, I separate batches of tobacco with wide-open, quart-size Ziplock freezer bags, which seem to tolerate the heat well.

Bob

EDIT: With regard to plywood, you would need an exterior grade to withstand the humidity. I suppose you could run the kiln for several weeks at the highest likely temp, in order to outgas the plywood. If the formalin and glue smell go away after the shakedown run, then you'd probably be in good shape.

 

[dkh2]

The ignition point of wood is 525ºF. Most fermenting kilns are kept below 140ºF. Even a flue-cure kiln would only be going up to 190ºF at the most. (Actually, the wood frame buildings at Phantom Ranch--at the bottom of the Grand Canyon--are periodically subjected to daytime temperatures over 120ºF.)
My small kiln is made of solid wood plank, and has on occasion been taken up to 139ºF. I don't worry about the wood. My remote digital hygrometer, mounted inside the kiln, is rated to operate up to 150ºF. Hopefully its plastic case is also rated that high. Within the kiln, I separate batches of tobacco with wide-open, quart-size Ziplock freezer bags, which seem to tolerate the heat well.
Bob
EDIT: With regard to plywood, you would need an exterior grade to withstand the humidity. I suppose you could run the kiln for several weeks at the highest likely temp, in order to outgas the plywood. If the formalin and glue smell go away after the shakedown run, then you'd probably be in good shape.

You got a freezer bag in there ?
I got a couple bags of some Burley I need to cure.

 

[deluxestogie]

The quart-size Ziplock freezer bags seem to hold up fine in the kiln. Each bag remains open, and has its closure rolled down, like a shirt sleeve, to allow the moisture to stay at kiln RH. I've run a few tiny batches in Ziplock sandwich bags. Although they came out intact, they appeared to be right at the margin of their thermal stability. I haven't tried it with bags thinner than that.

My bags go into a wire basket inside the kiln. The basket holds them pretty much like folders in a file cabinet, so I can easily read the labels by flipping them forward or backward. A full kiln seems to maintain a more stable temp and humidity. Over-full, and some of the bags dry out while others get too moist. Any bag too close to the thermometer/hygrometer sending unit causes the readings to be off. I should note that my kiln relies entirely on convection to circulate the air. I use no fan.

Bob

NOTE: If my kiln were large enough, I would use a wire basket from a bicycle, and do batches in gallon-size Ziplocks.

 

[dkh2]

My kiln temperature keeps falling below 120 all the way down to 106 especially at night.
have any of you guys ran a kiln below the 120 temperature and still had good tobacco ?

 

[Daniel]

I don't think the rise and fall will hurt. If it bothers you you can just add more power (higher wattage bulb). YOu may end up with a situation that it ferments during the day but not as much at night. Still it is getting the job done.

 

[dkh2]

What do you guys think of this the temp goes to 250F or 125+ C and 100% (Naturally) Humidity.
32 Bucks at Home Depot, I'm thinking that if it goes all the way to 250 degrees maybe it will withstand
the rigors of a kiln for several months at a time.

Measures temperature and humidity. Aluminum case with flange mounting. Attractive design.
Temperature range 30 to 250 F. From 0 to 100 percent RH.

Link to home depot

http://www.homedepot.com/webapp/wcs/stores/servlet/ProductDisplay?langId=-1&storeId=10051&catalogId=10053&R=202735076&catEntryId=202735076

 

[Chicken]

im going to do my construction out of '' hard wood''

im going to use the closet of a 50's era camper,,,, luckily they made them to last with hard wood instead of pressboard

 

[Cerasaan]

I hung some leaves that had dried in the bathroom then I took a shower and it's pretty humid in there now
but there still dry as a bone.

I guess that means you gotta hang out in the shower longer!