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DIY Kiln from old refrigerator

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I have looked at eHow and got some info on this DIY project. I wanted to check with the experts as I'm sure that some of you have followed this path for a kiln. Been saving an old referigerator for this- runs but doesn't cool. I'm thinking all the freon is gone. Not worth fixing.
Looking for advice, do's, don'ts, ideas for best results. Have several pieces of bartlett pear to dry and turn when dry. Seems bartlett pear trees don't tolerate high winds.
 
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What happens in your "kiln" generally involves reduction in Relative Humidity by elevating ambient temperature. This allows the air to carry more moisture than it did. If you then carry the moister air away with convective or enhanced ventilation, it will allow more moisture to leave the wood ... et cetera.

You can use the benign neglect method and hope for a good outcome, or you can use a hygrometer and regulate the RH through warmth or ventilation. That's what they do in real kilns. Turn, Dry, Turn will get you to the final product with greater success, and probably less time than trying to nurse several lumps through the drying process.

Legally, the freon must be handled professionally.
 
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I have looked at eHow and got some info on this DIY project. I wanted to check with the experts as I'm sure that some of you have followed this path for a kiln. Been saving an old referigerator for this- runs but doesn't cool. I'm thinking all the freon is gone. Not worth fixing.
Looking for advice, do's, don'ts, ideas for best results. Have several pieces of bartlett pear to dry and turn when dry. Seems bartlett pear trees don't tolerate high winds.

Cantact Kelly Dunn, he has several of these and is the real expert.
 
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I forgot to mention- the refer has a top freezer. I was thinking of putting a large diameter PVC pipe from the refer part up through the freezer. Also, I have a C-frame motor with a fan blade. Would this be an advantage to either drawing out the moist air or using it to move the air in the refer part?
Michael, the freon is gone as I mentioned earlier.
 
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You certainly don't need that kind of fan power. Lots of people just let things go by convection, putting a heat source near the bottom.

Open the door to exchange the air. If you want a fan, couple it to a humidistat. Nice 12V pancake type, perhaps.
 
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John, if the fridge are self-defrost , why not use that fan ? you may not need a fan unless the heat and moisture get too-high, a light bulb for a heat source will provide its own air movement as the air warms up
 
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Ray, I was thinking about using the fan on top to create a draft to pull the air through. However, I am thinking that this might create too much air flow. Maybe better to allow natural convection to take place. I might just remove the top freezer door and let the air/moisture come out there.
Thanks to all for the suggestions.
 
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I'd put the fan - if any - at the bottom. Convection might just find least resistance and leave the stuff out of the mainstream languishing in mildew. Pushing and creating turbulence from below would do things better. If you do a fan, and don't care to get too elaborate, turn it on three times a day for twenty minutes each or such. Simple timers will do.
 
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Ray, I was thinking about using the fan on top to create a draft to pull the air through. However, I am thinking that this might create too much air flow. Maybe better to allow natural convection to take place. I might just remove the top freezer door and let the air/moisture come out there.
Thanks to all for the suggestions.

I would not remove the door until I try it with the door part of the way open
how big of a hole did you cut in the fridge bottom ?
 
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Why not use the upper freezer area as part of the kiln. Use a hole saw and put a 2" or so hole towards the corners and one near the middle. Then drill a 2" hole in the top of the fridge for moisture to escape. Add a piece of wood or galvanized steel or lexan cap over the exiting hole so you can swivel the cap to adjust the opening from fully closed two fully open.

When you set up the kiln make sure the light fixture is on a rack kinda like a drying rack you would use in the kitchen also put the fan on that same rack. This will keep them off the floor of the inside of the fridge so they won't ever sit in water that may drip down. Also a good idea to put some type of cover over them so dripping water won't drip into them (this does not have to be fancy).

When you run the kiln I would close the cap on top and start the light and bring it up to temperature you can run the fan if you choose. BTW and old computer fan would work fine for the size of kiln you're talking about, just protect it with a cover. Then do as MM said and run the fan two or three times a day for 10 to twenty minutes with the cap open maybe 1/2 open.
As MM said a hygrometer will help in determining how far to open the cap and how often to run the fan and for how long. You'll have to play around with it but that is half the fun with new toys.

Good luck,

Dale
 
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Haven't started on it yet. No holes or anything done- just wanted to see my options before starting and royally messing things up. Will pull the refer from the wall and start removing stuff that isn't necessary. I like the idea of a timer- heats the interior and lets the air clear before starting again. I'll look at timers at Wally World and Lowe's.
Again, thanks to all for their input!
 
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