On 3/11/2014 11:10 AM, Michael wrote:
On Monday, March 10, 2014 7:14:10 PM UTC-5, Jeff Thies wrote:
On 3/10/2014 3:59 PM, Michael wrote:

I'm going to make an insulated solar kiln to dry out 6 -8 foot stock. Any advice. It's just going to be an insulated box with repurposed house windows tilted at 45 degrees (Wisconsin),



I don't know the wood bits, but I do know solar.



The angle varies by season. Whatever angle about an hour before solar

noon. You can also add reflectors to bounce more light in. Polyiso foam

RMax, or reflective bubble wrap. With either you can tape/tack together.





I use corrugated panels like SunTuf when I make anything solar. That

brand also has a UV shield, if you wanted to add a layer of mylar for

extra insulation.



Thinking outside the box, probably too far out:



The solar heater can be separate from the wood.



http://en.wikipedia.org/wiki/Wood_drying



It seems that drying benefits by air movement:



and a small fan to circulate air. Any important things I need to keep

in mind?



Larger fan and the cross section small so the air speed is higher.



I use fan forced solar hot air to heat my house during the day and I can

see how solar forced air could dry wood. A mix of recyled and fresh air.



Arduino humidity/temperatu



http://playground.arduino.cc/main/DHT11Lib#.Ux5T8fldV2Q



I think keeping a relatively constant humidity may be more important

than the temperature.



Thanks.



Thanks for the good thoughts. My goal is to keep the costs way down. I have most of the stuff laying around already, including windows, but not the 3/4 sheets of plywood or the fan.

Forget the 3/4", Frame it up and use the rMax polyisocyanurate for the
sides. Reflective side in, you can paint the exterior if you like or
cover with thin ply. The half inch ($10) should be OK:

http://www.rmax.com/downloads/DataSheets/rmp3.pdf

There is little advantage of having a higher R value as most of the heat
will escape through the glazing.

The suntuf looks like a great suggestion. I'll see where the budget is.

It's very tough. Just make sure no direct sun can hit the reverse side.
If so, Lowes has a similar product that doesn't have the UV shield
because it does not need it. For what I do, the UV shield is important.

Also, you don't need much wood in the structure. You can frame it in
with 1" or 3/4" PVC pipe. Use self tapping screws with the gasket. You
will need to paint the PVC if it is exposed to UV. I've made a structure
just out of the Lowes panels and 1" PVC and 2 x 2s. Very strong.

If you just need to try it out and last a season or maybe two, get the
clearest 4 mil or greater poly rolled sheet. Clear poly is seldom very
clear. Vinyl will be clear and seems to hold up a bit better that poly,
although more expensive. Ace Hardware, I believe. Clear shower curtain
liners are a lower quality vinyl but may be OK.

I'm all about cheap!

Jeff