Portable solar kiln?

[Daren]

I am thinking about a solar kiln that can be set up and taken down and moved around. (like one of those portable carport things) I am a plumbing/heating contractor and when I install a "in-slab" hot water heating system with all the tubes and boiler, I insulate under the slab. I use a product called Insul Tarp, it is basically 2 tarps (one silver, one black) with layers of insulation sandwiched in between. It is a vapor barrier, it insulates against heat loss into the ground and reflects heat back to the room, there is a layer of aluminum sandwiched in there too. It is super tough, we drive Bobcats over it after I lay it, but light and easy to work with. Okay, back to my idea, why couldn't a guy build a frame (or just buy a portable carport) and cover the ground, back and sides with Insul Tarp. Then I have looked on the web and found 2-layer green house glazing that comes in a roll for the solar collector. I don't fully understand kiln operation, that is why I am posting. I have read alot about fan controls, moisture bulbs... Does it have to be that high tech? How about a simple "remote weather station" like I have on my R.V. ,it tells temp. and humidity on a outside of the camper, just put the sensor in the solar tent and and monitor from the outside. I know you have to have air flow, I could do a fan with 110v and timer or a solar collector and low voltage fan. When the sun is bright enough to make electricity I would guess that is when you are blowing the most moisture out of the kiln because it is hot and causing wood to dry? I guess the vents would have to be manual flaps with a zipper or velcro or stick on magnet strips. How many pieces of the puzzle am I missing?

[Daren]

I needed to add that I would only be sticking air dried lumber in to finish it off. I would not try to get any decent product from fresh cut in such a simple set-up.

[Ianab]

Hi Daren

As air dried wood is pretty forgiving about drying conditions I can see no reason why it wont work.
The high tech approach gives better control to achive the fastest drying with the least degrade, so temp, airflow, humidity figures become important.  To get wood from 15% to 10% you basically just need to stack it someplace and blow some warm air over it for a few weeks.

The wood will still be effectively air dried, but it will be down to a low m/c and ready to use.

How does the plastic sheet handle UV though? You dont want to go to all this trouble and have it break up after 12 month sin the sun?

Cheers

Ian

[Daren]

Yes, the glazing sheet material I saw had a warranty, I think it was 5 years. I just need an way to get the some of the lumber I have dry enough for indoor use. It's all hanging around 15%. I want to get some below 10% and start dead stacking at another building I own without having to worry about it. I started cutting for outdoor use and small amounts I could air dry then bring in the house during the winter to finish drying. Now that I have a mill, I sort of got into the lumber selling business by accident. I am getting a fair amount of walnut given to me by a excavator buddy of mine  ( 30 gift logs showed up last weekend and the same guy called and has 30 more he is bringing by today).  I have sold some a.d. lumber, but could sell more and for more $ if it was really dry. I was not planning on getting into the lumber business, with a real kiln and all that. I just bought my mill for myself and was going to try to do a little custom cutting to pay for it. Now I have went out and bought a skid steer with a grapple bucket to move logs, my wife has to park at the neighbors sometimes 'cause the yard is full of logs.  I built a 6 car garage, but all of my vehicles and my fishing boat set outside 'cause the shed is full of stickered wood. I have to get this fixed.

[scottr]

Daren , there is solar kiln (dryer #20) that will fit your needs on http://www.woodweb.com/knowledge_base/Solar_Kiln_Designs_4.html                                              Scott

[Daren]

Scott
Thanks, I check out Woodweb alot. I must have just missed that. I am glad to see there is a working model of a basic tent dryer. I am definitely going to build my version, if the sun would shine I would be in business. Spring rains are here.
Daren