Really small kiln?

[Pete Staehling]

I build musical instruments so my work pieces are small and I consume relatively small amounts of board feet. That said I like to salvage dead trees and have a ready supply of dead cherry trees since they tend to live only until they are 10-14 in diameter here. I have used some blown down trees rough sawn by eye with a chainsaw and then milled at home on a 14" bandsaw.

I have been surprised that the planks seem to dry pretty fast just sitting in the shop, but as I do more of this I think maybe a small kiln might make sense. My work never requires finished pieces more than 3' long and most are less (most of it is ultimately sawn into thicknesses of 0.090-0.125"). I could see a kiln as small as one accommodating only a couple dozen board feet and a maximum length of only 3-6' working for me.

Has anyone used or seen a kiln that tiny? Is there any reason it is an especially bad idea?

Solar sounds appealing, but I am not sure if I can find an acceptable spot that gets more than a few hours of sun per day. I am in Tallahassee so the sun is pretty hot, but I just don't have a place with long hours of sun.

I wonder if something quite small with a small muffin fan and a light bulb or two for heat would be at all practical.

Thoughts on any of that? I have only had a minimum of experience with this and probably have done everything wrong so far, but I have been happy with being able to produce small quantities nice useable stock despite my crude approach.

[david privett]

how about a small metal shed with a couple of gable vents and a fan. I believe that it would be best with a concrete floor to control pests and moisture. I lived in Clearwater ,fla. and I remember how hot the old shed got when closed up.

[Bob Bouis]

Use a 120v humidistat to control a light bulb in an insulated box with a fan in it.

[Jim Andrew]

If you put in the time to read about kilns, a concrete floor does not work. You want a raised floor, insulated. There is a lot posted on forestryforum about solar and other kilns. One guy uses a room dehumidifier to remove the moisture from the kiln, so it does not have to be vented.

[Keith Outten]

Find an old horizontal freezer for the box. If you have a friend with HVAC skills you can convert a small dehumidifier that you can install in the box and then control the drying cycle.

[John TenEyck]

I built a dehumification kiln as described in FWW Nov/Dec. 1991. My kiln holds about 275 BF, but can easily be scaled to nearly any size, including really small.



It has a semi automatic control system; requiring attention only once a day, and will idle w/o damage to the wood if I go on vacation, etc. Three 100W bulbs provide the initial heat up to its 110 F operating temperature and the dehumidifier takes care of removing the moisture and provides heat as well. You could actually build an even simpler control system as shown in this diagram:



Having said and showed all this, I've found in practice that it's far better to air dry my lumber to less than fiber saturation point (28% MC) before putting it in the kiln. That only takes 4 to 6 months were I live for 4/4 lumber. Then I put it in the kiln and dry it to 6 - 8% MC in less than 2 weeks.

John

[maximillian arango]

Depending on how small you want to go you maybe able to do a vacuum kiln, creating a vacuum will lower the boiling point of water and using a heat lamp or some sort of heating element should net you what you want,


back to lurking

[John K Jordan]

Woodturners often use an old fridge or freezer cabinet to make a small kiln. Google has lots of info. Here is a write-up about one pro woodturner Cindy Drozda made:

https://www.google.com/url?sa=t&rct=...zZA7Aw&cad=rja

JKJ

[Bill Jobe]

A microwave is pretty small.
Seriously, the last 3 pieces I made I dried in a microwave.
The problem with that is no universal method. It' all by guess and by golly. But you can dry wood fast.