Solar kilns

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Location
Central (upstate) NY
Does anyone have any experience with solar kilns? I've got a bit of maple that has been sitting under a tarp since last year and I'm wondering if it is worth my time to build one of these things.

Thanks!
 
If that maple was stacked so air could circulate, it may be OK now.
However, a member of my woodturning club is in the business and solar kilns all his wood. The room faces north, is about 15' wide and, maybe 10' deep. The north wall is simply a sheet of visqueen (sp?) about 12' tall. There are a couple small fans to bring air in and move out. That's it. Wood is stacked and stickered. He says that the room, in daytime, is always 75 degrees warmer than outside air. I have no idea how long it takes to dry the wood. Sure it varies with type and thickness, time of year, etc.
 
Most of the maple is 4/4, but some is 8/4 or even 10/4. It is stickered, although it looks like it isn't flat resting after the winter - when we first got our dogs we bought one of those little self-contained kennel deals and then never used it. I put the wood in there and it has tilted and is resting against the kennel - still stickered though. :huh:

My wood storage room tends to get kind of warm, especially if I open the curtains, maybe it is time to bring it on in soon. Not tonight though, I noticed a huge puddle of water on the tarp and took to cordless shop vac out to give a little suck on the end of the siphon hose I have out there. Hehe, I took some used, improperly cleaned brewing siphon line, screwed in an HF male air fitting for weight and tossed her in. I periodically go out with the cordless shop vac to get it going - this is my first time since winter - I am impressed that the HF tarp is still loving the huge lake of water that it is holding.

Thanks Frank!
 
Mark, Being in the upstate area, I would look into building a kiln that uses a dehumidfer(sp) They are easy to control and will dry the wood quicker then a solar kiln.
 
I've got a solar kiln and I have had good results with it. I say good, and not great, awesome, or fantastic only because I framed the thing and never really got beyond that. I am sure if I insulated the thing, painted the inside black and installed circulating fans it would dry wood much quicker.

As it stands now it gets quite hot in the summer when the sun hits it,even as drafty as it is. I have never noticed any boards to adversely warp from it. In about 3 months time I can get wood fresh off the sawmill to dry. Mine is a bit small, at 4 feet wide, and 16 feet long and can hold a few hundred feet of wood. Its also wired for lights and outlets. I would certainly recommend anyone to build one.

The good thing is, you can not over-dry wood in the thing. The temp does not get so high that it can honeycomb, or dry out your wood too fast. At the same time you can use a solar kiln for wood storage, since the heating side of the thing relaxes at night, giving the wood a rest period from drying.

Still there are improvements I would like to make and here are some of those ideas. The first is to insulate it the living crap out of it, install some circulating fans and paint the inside black. Then I would like to install some baffles and install a small dehumidifier I have kicking around, to jump start the drying process if need be. Just a flip of the switch and you would be drying...even at night. Some temp gauges running to my shop would also be nice, along with a remote moisture meter too so I could keep a better eye on the dryness of the wood.

One other option I thought of, was to heat water via a compost pile, then pump the heated water through baseboard heat radiators into my solar kiln via slow circulation. By doing this I could raise the temp of my solar kiln, and dry wood even in the winter, or on cloudy days.

Here is a picture of what I have now anyway, but as I said I never got much beyond the framing stage. I've just had other things to build that were more important...like a house :)

Drying_Kiln-454x341.jpg
 
Travis - you got me wondering if (budget permitting, which means not this year) if I were to build one, maybe investing a solar panel from HF to run the fans / dehumidifiers.

It looks like your setup is just exterior grade ply? Would setting the whole thing up on some PT 4 by 4's be a sufficient elavation to keep it from rotting? And is black needed or would any old dark colored "oops" paint do?

What kind of insect control is done with these things? Both against the woodeaters and the "let's see if your harbor an anaphalactic shock reaction you didn't know about" kind.

Now I need to figure out how much sun the flat spot where I would like to set this up gets. I guess I could always build it some where else if needed.

Thanks!
 
If that maple was stacked so air could circulate, it may be OK now.
However, a member of my woodturning club is in the business and solar kilns all his wood. The room faces north, is about 15' wide and, maybe 10' deep. The north wall is simply a sheet of visqueen (sp?) about 12' tall. There are a couple small fans to bring air in and move out

:huh::dunno::huh::dunno:
Errr, North?

Does this friend of yours live south of the equator? :rolleyes:
 
Mine was cheap, but I get my building lumber for the same price I get my woodworking lumber (from the property) which is the whole reason why I have a solar kiln.
 
I thought about getting our sawmill going into full production, but I have a feeling a new sawmill will be going up in town pretty soon and it will sell lumber at a lower rate :(

Just as soon as the mud goes away I think I will head back into the woods though and get the old Travis Johnson Firewood business up and running again. Everyone around here says the same thing...this year I'm getting a woodstove.

I'll be ready for them! It will be interesting to see which way lumber prices go though. I know Hardwood Pulp prices (for making paper) have topped 100 bucks a cord...an unheard of price. Hardwood lumber is sure to follow.
 
Scot Kelly has one. He's used it for quite a while now. I'm building one kinda like his.

You actually have to be very careful. It will dry way too fast, if not tended to. Your part of the country I doubt would cause that issue, but it still needs watching closely when you 1st load it. If it is summer time with lots of sun down in our neck of the woods, it can reach 140-160 degrees F quickly! I think Scot usually lets it sit outside for a week or two before loading, to get that 1st mositure out.

anyway 2 cents

Jimmy
 
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