Expeditided Wood drying / Solar Kiln

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I found the most bang for the buck is just shrink wrapping the wood. Its not perfect but it works very well. I had a stack get up to 165 degrees this past summer.

It only takes a few minutes per stack and the cost is negligible. I'm really not going to invest more time and money than that. Defeats the purpose of burning wood to save money.
 
I found the most bang for the buck is just shrink wrapping the wood. Its not perfect but it works very well. I had a stack get up to 165 degrees this past summer.

It only takes a few minutes per stack and the cost is negligible. I'm really not going to invest more time and money than that. Defeats the purpose of burning wood to save money.

What type of shrink wrap do you use? How far down the stack do you wrap? To the ground or do you leave several inches for moisture to escape?
 
What type of shrink wrap do you use? How far down the stack do you wrap? To the ground or do you leave several inches for moisture to escape?

My wood is up off the ground so I wrap as far as I can and leave the bottom open. I've seen people that close off the bottom and add a few holes to let the condensate out. Apparently that keeps more heat in. With the bottom open I still hit 165 in the summer. I've messed with putting 2 small holes near the top to vent humid air and it does lower the temperature a bit. I'm not sure it makes much difference overall either way.

I don't know the particulars on the wrap because I've gotten it for free but I'm sure whatever wrap they have at home depot or lowes will work. I have wrapped single stack rows and 2 pallets with the wrap. If you want to do the top easily on a stack that's wide like a pallet I'd get some plastic at home depot and cut it to hang over the sides a bit and then start wrapping the sides. You can do the top with shrink wrap but you lose a lot trying to keep going back and forth to cover the surface.

I'm sure there are many methods that work a little better, but like I said, in my opinion this method yields the most benefit with the smallest amount of time and money.
 
If you want a vent, try the UK approach of a green house where they slope the top of the stack/greenhouse slightly toward one end and just leave a small vent opening at the high end. By sloping the peak upwards all of the hot moist air vents at a single location and more of the top can be left enclosed to build even more heat. Most of the threads I have read, here and elsewhere, showed much better results with clear plastic than with black plastic because we are not trying to heat the air, we want to heat the wood itself and you mostly heat the air with black plastic. Unless you use UV stable plastic, like green house plastic, you will be replacing it at least annually if not sooner.
 
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Update going into season 2.

The Solar Kiln is still the best drier I have.
Though small (face cord only), it works great!

This year plenty of free grabs of fresh cuts to be had and actually had to stop. Good problem to have!

The Big Box unit is gone. Just didn't cut it..
The S&G covered has become the secondary drying as it leaves the Kiln.
I've re-worked the cover from the original design and still working on that a bit.
Need to learn how to weld plastic to make a good cover.

Temps in it are 10-15% less than the Kiln, but still, today 30F outside and the temp inside is 50F.
The Kiln approaching 60F

I love how this experiment went. Learned a lot from it, through trial & error, but mainly from your all input!

Thanx Folks!
Well done, Robert. You came up with and tried three designs, all good ideas, and discovered which ones worked best, applying some scientific method, and shared it with the interested community. Smart and effective. I enjoyed reading about your work.
 
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If you want a vent, try the UK approach of a green house where they slope the top of the stack/greenhouse slightly toward one end and just leave a small vent opening at the high end. By sloping the peak upwards all of the hot moist air vents at a single location and more of the top can be left enclosed to build even more heat. Most of the threads I have read, here and elsewhere, showed much better results with clear plastic than with black plastic because we are not trying to heat the air, we want to heat the wood itself and you mostly heat the air with black plastic. Unless you use UV stable plastic, like green house plastic, you will be replacing it at least annually if not sooner.

There's a guy I was communicating with that curved the ridge towards both ends. A bend in the ridge. I agree, venting at the top is key, inlet at the bottom and balancing the two to draft well.

Thank you for you input!
 
Well done, Robert. You came up with and tried three designs, all good ideas, and discovered which ones worked best, applying some scientific method, and shared it with the interested community. Smart and effective. I enjoyed reading about your work.

Thank you! I took a lot of advise from here as to what they really wanted to see in this experiment.
 
I finally sat down to Sketchup to learn how to use it.
Thank God for the Engineering Toolbox!
What a Plugin!

Anyone familiar with Sketchup and knows of a Plastic sheathing module, please refer me to it.
Well, that and how to share the design here..

I've drawn the concept of what I'm going to construct as my kiln.
Basically, it follows my S&G cover with a few adaptations of the kiln I made.
The goal was to have something anyone can build for short money and not have it a permanent structure.
Something you'd (me), would be taxed on.

I also want something I can load and leave.
Moving wood into and out of the kiln was a real pain!

We all must cover our wood.
Why not do it efficiently and expedite the drying process.
Besides, not all of us have acreage to put several stacks for years on end.

Again, if anyone here has knowledge in Sketchup, please contact me.
I'd like to finish this and share it.
 
Anyone familiar with Sketchup and knows of a Plastic sheathing module, please refer me to it.
Well, that and how to share the design here..
If you just want to share a design with other folks who have a drawing program, check to see if you can save the file as a DWG or convert the finished file to a DWG. Most drafting software can import DWG files. If you want to just display a static picture, try using the BMP file format that windows uses. Worst case, print out your picture on a sheet of paper and take a good quality picture of the printout and publish the picture as a JPG.

I just went on line to find sketchup and it seems it can export files as JPG or BMP so sharing should be easy. Just store a JPG copy on line anywhere and refer to its IMG location from a post. If you store a JPG on Photobucket the photobucket software will automatically give you a reference in the IMG reference that you can use. Only the PRO level of sketchup supports a DWG export so unless you paid for PRO I doubt you can use that function.
 
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Thank you. A good friend gave me a great DVD on Sketchup that shows how to share in several different ways.
Shortly, you guys will see something from me.
The DVD shows me how to explode it into parts which is really cool!
That I'm learning.

Thank you for your input!
 
Let's try this
First view the basic over-view
Solar%20kiln%20parts_zpssdthcg2e.png
Solar%20kiln_zpswu7ohysi.png
 
Okay, that was weird..
I'll work on this.

The second picture should have been first, but what the hey.. First attempt.

The length of the unit is determined by the glass you have.
Trying real hard to get to at least a Face Cord to fit inside.
I came very close.

The gap at the top should be about 1/4 of the spacing at the bottom or less.
I'll let the HVAC folks talk about proper inlet to outlet to induce flow of air.
I have spacers on the back side to adjust the gap.
I like this! During the Summer/Fall season it came be larger.
Now, in Winter, I can reduce it and allow a bit more heat to build up.

I have a plastic ground cover (actually hard black plastic sheet) to avoid the moisture draw.
The gap at the bottom is high due to I have grass that grows around it and have to compensate for it.
All the wood is stacked on cut-down pallets to fit the unit.
This not only keeps it off the ground cover, but allows for air flow.

The principles here are basic ones.
The Sun must touch the wood.
The spacing around the wood must be limited.
Air must flow.

Have fun in trying new ideas.
Mine is not new, just worked from others that have tried before.
This one works very well for me!

The next is the PVC Hoop Cover.
A version of the S&G cover that surprised me on how well it does.
 
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PVC%20Hoop%20Solar%20Kiln_zpswgvatq5d.png

I'm still working on the drawing, but this gives you an idea of what I'm doing.
With a simple Plastic Sheet covering that would roll up in the front, you have your stack and a way to get the wood without loading and moving the wood from the Kiln (shown before).
Again based upon the basic principles of single stack, sun touching the wood, and air movement.

I have a rough version running now in my yard.
Of course a ground cover and stacked on cut-down pallets.
I'm amazed on how well it does.
 
If you just want to share a design with other folks who have a drawing program, check to see if you can save the file as a DWG or convert the finished file to a DWG. Most drafting software can import DWG files. If you want to just display a static picture, try using the BMP file format that windows uses. Worst case, print out your picture on a sheet of paper and take a good quality picture of the printout and publish the picture as a JPG.

I just went on line to find sketchup and it seems it can export files as JPG or BMP so sharing should be easy. Just store a JPG copy on line anywhere and refer to its IMG location from a post. If you store a JPG on Photobucket the photobucket software will automatically give you a reference in the IMG reference that you can use. Only the PRO level of sketchup supports a DWG export so unless you paid for PRO I doubt you can use that function.

Problem I'm finding is not being able to upload a file to this site.
Guess I have to put it on the 'Cloud' and give access?
Is that possible?
Haven't gone there before... But I'm willin'!!
 
My current plans are to build a wood shed, maybe next year, and to use clear roofing, with gaps in the walls for airflow. But the wife did mention she'd like a greenhouse, maybe a combo woodshed greenhouse is in order ;)

Good luck and please keep us posted.

That would be like having a combo scrapbooking room/man cave.
 
If you want to link to a picture in BMP format just upload it to Photobucket then use the IMG link they provide to show it here. This is a picture of my chainsaw in JPG format that I have stored on Photobucket. I use a line feed/return stroke before I paste in the link so the picture will align to the left.
555at_new800_zps9wmtltcb.jpg
 

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