Solar kiln wood drying

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Woodsplitter67

Minister of Fire
Jan 19, 2017
1,967
Woolwich nj
I just want to start with that this idea was not mine. The original poster of the idea was Poindexter. I read this post back in may. I used his idea did some modifications. I just want to say thanks for sharing this. I just wanted to see if it would work here in the northeast and with harwoods

I picked up a bunch of log lenth wood in early may of this year. The wood was freshly cut, green oak and cherry. I cut the log lenth to all 18 in. There wasn't enough room in the wood shed so it wound up on the racks i have

This past july i decided to check my wood which i am 3 years ahead on and in various stages of drying. I checked the wood on the racks and the wood mesured 34% 36% for the oak and around 28 to 30% for the cherry. I decided to experiment with the solar kiln. I put it together a cheapo version for about 40 bucks with some wood i had at my home, some zip ties, plastic, and advice from Poindexter. With in 2 hours my son and i had it running. With in 2 hours i put an air prob in it and it was up to 118 degrees inside. The kiln was started on July 8 2017

My son and i had to fix the plastic cover due to the high winds we have had so while it was open I did a test of the wood
The split lenth is 18 inches. I split and tested the wood on the fresh side with the grain. The oak droppd from 34% to 9% and the cherry droppd from 30% to 2% all of this in 3 months time.
This is the oak top 2 pics. The cherry is the last 2 pics. The splits are on the larger side and i was super surprised of how fast it seasoned with the split size being 6 inches or greater. I just cut the seasoning time down from 3 years to 3 months.
20171125_111802.jpg
20171125_113709.jpg
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20171125_114419.jpg
 
Last edited:

Easy Livin’ 3000

Minister of Fire
Dec 23, 2015
2,920
SEPA
I just want to start with that this idea was not mine. The original poster of the idea was Poindexter. I read this post back in may. I used his idea did some modifications. I just want to say thanks for sharing this. I just wanted to see if it would work here in the northeast and with harwoods

I picked up a bunch of log lenth wood in early may of this year. The wood was freshly cut, green oak and cherry. I cut the log lenth to all 18 in. There wasn't enough room in the wood shed so it wound up on the racks i have

This past july i decided to check my wood which i am 3 years ahead on and in various stages of drying. I checked the wood on the racks and the wood mesured 34% 36% for the oak and around 28 to 30% for the cherry. I decided to experiment with the solar kiln. I put it together a cheapo version for about 40 bucks with some wood i had at my home, some zip ties, plastic, and advice from Poindexter. With in 2 hours my son and i had it running. With in 2 hours i put an air prob in it and it was up to 118 degrees inside. The kiln was started on July 8 2017

My son and i had to fix the plastic cover due to the high winds we have had so while it was open I did a test of the wood
The split lenth is 18 inches. I split and tested the wood on the fresh side with the grain. The oak droppd from 34% to 9% and the cherry droppd from 30% to 2% all of this in 3 months time.
This is the oak top 2 pics. The cherry is the last 2 pics. The splits are on the larger side and i was super surprised of how fast it seasoned with the split size being 6 inches or greater. I just cut the seasoning time down from 3 years to 3 months.
View attachment 216534 View attachment 216535 View attachment 216536 View attachment 216538
3 months down from 3 years. Pretty darn good.

Wonder if it were three months other than July, August, September, what the results would be. If you could get 3 cycles out of each kiln annually...

I think this is a viable solution to many of the folks who find themselves without 2-3 years of runway.

Nice project Woodsplitter , thanks for reporting.
 
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Poindexter

Minister of Fire
Jun 28, 2014
2,381
Fairbanks, Alaska
Welcome to my world last year. You will probably want to mix in some wetter wood when you go to burn that stuff, it will burn hot hot hot and fast fast fast.

Be sure to not share your results with @BKVP because he'll get heartburn, @Ashful will face a paradigm shift. I can think of a handful of folks who might clog their sewer pipes with bricks. @begreen ?
 

Easy Livin’ 3000

Minister of Fire
Dec 23, 2015
2,920
SEPA
I just want to start with that this idea was not mine. The original poster of the idea was Poindexter. I read this post back in may. I used his idea did some modifications. I just want to say thanks for sharing this. I just wanted to see if it would work here in the northeast and with harwoods

I picked up a bunch of log lenth wood in early may of this year. The wood was freshly cut, green oak and cherry. I cut the log lenth to all 18 in. There wasn't enough room in the wood shed so it wound up on the racks i have

This past july i decided to check my wood which i am 3 years ahead on and in various stages of drying. I checked the wood on the racks and the wood mesured 34% 36% for the oak and around 28 to 30% for the cherry. I decided to experiment with the solar kiln. I put it together a cheapo version for about 40 bucks with some wood i had at my home, some zip ties, plastic, and advice from Poindexter. With in 2 hours my son and i had it running. With in 2 hours i put an air prob in it and it was up to 118 degrees inside. The kiln was started on July 8 2017

My son and i had to fix the plastic cover due to the high winds we have had so while it was open I did a test of the wood
The split lenth is 18 inches. I split and tested the wood on the fresh side with the grain. The oak droppd from 34% to 9% and the cherry droppd from 30% to 2% all of this in 3 months time.
This is the oak top 2 pics. The cherry is the last 2 pics. The splits are on the larger side and i was super surprised of how fast it seasoned with the split size being 6 inches or greater. I just cut the seasoning time down from 3 years to 3 months.
View attachment 216534 View attachment 216535 View attachment 216536 View attachment 216538
What did you use for the plastic wrap?
 

Woodsplitter67

Minister of Fire
Jan 19, 2017
1,967
Woolwich nj
3 months down from 3 years. Pretty darn good.

Wonder if it were three months other than July, August, September, what the results would be. If you could get 3 cycles out of each kiln annually...

I think this is a viable solution to many of the folks who find themselves without 2-3 years of runway.

Nice project Woodsplitter , thanks for reporting.

I really think you would be able to season a minimum of 3 cords to under 20% in a year. This really would come in handy for someone with little room at there home or someone who got behind
 

Woodsplitter67

Minister of Fire
Jan 19, 2017
1,967
Woolwich nj
Kiln pics? :)
Here are the pics from the first day the we put it together.. the temp pic was taken not to long after it was put together and it wasn't verry hot that day.. I think it wasn't even 80 at this point and was a mix of clouds and sun
20170708_120316.jpg
20170708_120414.jpg
 
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Woodsplitter67

Minister of Fire
Jan 19, 2017
1,967
Woolwich nj
Did you notice much condensation running down the plastic inside? Or did it seem that most of the moisture came out the vents?

All of the moisture came out of the vents. There was never any point in time that there was any moisture on the inside of the plastic. I think this was a really cool experiment
 

maple1

Minister of Fire
Sep 15, 2011
10,799
Nova Scotia
All of the moisture came out of the vents. There was never any point in time that there was any moisture on the inside of the plastic. I think this was a really cool experiment

That is quite interesting. You must have had your venting optimized - whether by design or by accident. ;)
 

Woodsplitter67

Minister of Fire
Jan 19, 2017
1,967
Woolwich nj
That is quite interesting. You must have had your venting optimized - whether by design or by accident. ;)

I had it vented in 3 places..Poindexter gave a little guidance on sizing
I had my ideas on it.. You need it to vent but not so much that the like doesn't heat up
 

saewoody

Feeling the Heat
Feb 15, 2017
456
CT
I had it vented in 3 places..Poindexter gave a little guidance on sizing
I had my ideas on it.. You need it to vent but not so much that the like doesn't heat up

Are the vents in the top corners and in the top center?


Sent from my iPhone using Tapatalk
 

Poindexter

Minister of Fire
Jun 28, 2014
2,381
Fairbanks, Alaska
On mine i run up to three cords in one plastic cell about 24 feet long with just one exhaust vent at each end at the top corners, so two exhaust vents total. For intakes i count on air leaks at the bottom where the plastic isnt fastened to the flooring.
 

Woodsplitter67

Minister of Fire
Jan 19, 2017
1,967
Woolwich nj
Are the vents in the top corners and in the top center?


Sent from my iPhone using Tapatalk

I had vents at eather end as well as one in the middle. The ones on the ends were a little smaller then what they should have been so i opened one up in the middle.
 
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Woodsplitter67

Minister of Fire
Jan 19, 2017
1,967
Woolwich nj
Nice. I think I'm going to have to try and build one of these for my wood racks to try it out.

Sent from my XT1585 using Tapatalk

Its really a great idea. I will be using this concept to dry the really large pieces like 6×6 size to speed up the seasoning time. There will dry in a matter of months not years and also I will not need to sit on as much wood as in the past I am sitting on 12 cords split and stacked as well as 6 cords in rounds and 2 cords in log lenth. The log lenth and rounds are at my shop. Instead of trying to be at least 3 years a head I can keep it to 2 years and have plenty of seasoned wood.

If your going to do this i have one suggestion. Check the MC of the wood every 2 to 3 weeks as i let mine go thinking it would take all summer to season and some of my wood droped to 2%
 

Tegbert

Feeling the Heat
Sep 15, 2016
404
Arlington Wa
So when would you have taken the wrap off? At what percentage?

How did you do your vents and how big are they?


Lopi Rockport
Blaze King Ashford 25
 

Woodsplitter67

Minister of Fire
Jan 19, 2017
1,967
Woolwich nj
So when would you have taken the wrap off? At what percentage?

How did you do your vents and how big are they?


Lopi Rockport
Blaze King Ashford 25

Thats more of a personal choice. What % do you want to run
For me next time i will pull my first load at 20% and let it drop from there the rest of the summer. For the last load of seasoning i would drop the wood to at lest 16 to 18% MC.
 

Poindexter

Minister of Fire
Jun 28, 2014
2,381
Fairbanks, Alaska
Do you have a picture of your floor system @Woodsplitter67 ?

When you wrap and unwrap is going to depend on your local weather pattern too. My typical weather is mild gentle scattered rains in May, sunny and dry June 1 to July 4th. Sometime between July 5 and August 10 the rains start, and keep on coming, and in September the rain turns to snow.

What worked for me this year was to leave the sides open right up until the rain came in July, then close the sides and wait for cool weather.