Fall/winter seasoning in Mini kilns

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Woodsplitter67

Minister of Fire
Jan 19, 2017
2,036
Woolwich nj
I have put together some mini kilns to season some of my wood faster. I have a friend that is in need of wood so Im helping him out. I put this together on October 2nd, obviously the sun angle is getting low so high heat temperature are not expected. It was a high of 70 degrees and the inside kiln temperature was 114... Not bad. Today november 24 it is 43 degrees the sun angle is alot lower and the inside wood temperature by my IR gun says the wood was 86 degrees. I believe that you can season wood fairly quickly with smaller kilns over the course of the fall, winter and spring. I dont think that the larger ones I have done in the past would be this warm.
The mini kiln is just a pallet with wood stacked on it. This kiln is exactly half a cord, 4x4x4. It is up off the ground higher then the other kilns. This is on 6x6 RR ties. The sides are wrapped with contractors stretch wrap, plastic put over top. The plastic was put on with the center being 14 inches high in the center and 2 small u shaped vents cut open. More wrap was put around the plastic to hold it in place. Im going to do a test split tomorrow to see how its going. I did test the wood prior to stack and the wood was in the low to mid 30s.. hers some pics

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clancey

Minister of Fire
Feb 26, 2021
1,730
Colorado
Very interesting and let us know how your idea works--looks like it will do fine...Here is some reading literature for you..clancey
 
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Woodsplitter67

Minister of Fire
Jan 19, 2017
2,036
Woolwich nj
Along with 15 unwrapped pallets, here are this years 24 mini kilns, wrapped in May/June. Wood in upper half or so of each one is coming out at 10%, lower portion at 14%-16%. I leave the kilns intact until they are in the woodshed, under cover. I can put six in at a time which gets me through about 8 weeks.

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that looks good, Im trying to see what kind of results I can get in cooler weather. I haven't really tried to speed up the seasoning process in late fall early winter
 

jaoneill

Feeling the Heat
that looks good, Im trying to see what kind of results I can get in cooler weather. I haven't really tried to speed up the seasoning process in late fall early winter
Last year I had 8 pallets that I didn't get wrapped until early September. When I brought them in in late February they had gone from mid-twenties to mid teens but we had had relatively warm weather through until mid Oct. This year I tried leaving some splits a bit bigger and the larger (8" and up) weren't as consistently dry as the more uniform 5"-7" that I usually shoot for. Here is a closeup of aa pallet that I unwrapped tonight.

IMG_1282.jpg
 

Woodsplitter67

Minister of Fire
Jan 19, 2017
2,036
Woolwich nj
Thanks for posting your results.. This is the stuff im kinda hoping for. Im also hoping someone who cant store alot on their property sees something like this and helps them in the future with storage and dry wood. Also it would be nice to show that if your going to be short on wood that you could cut and split in September and burn in march/April with this setup.
 
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jaoneill

Feeling the Heat
Thanks for posting your results.. This is the stuff im kinda hoping for. Im also hoping someone who cant store alot on their property sees something like this and helps them in the future with storage and dry wood. Also it would be nice to show that if your going to be short on wood that you could cut and split in September and burn in march/April with this setup.
It is certainly a viable alternative for anyone to consider. That said, there are many variables in the wood, as well as the weather; size of splits and species of wood being the most obvious. At least here where we are, results would probably be substantially different this year from last year. Although our average temps were warmer later into the fall this year, we had overcast skies or rain most days, not a lot of sun.
 

ABMax24

Minister of Fire
Sep 18, 2019
1,199
Grande Prairie, Alberta, Canada
This makes me giggle, because it's totally climate dependant. You might knock a percent or 2 off softwood in a winter here with that method, but it's pretty hard to dry wood when its frozen. It would work to keep snow off the wood though.
 
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jaoneill

Feeling the Heat
This makes me giggle, because it's totally climate dependant. You might knock a percent or 2 off softwood in a winter here with that method, but it's pretty hard to dry wood when its frozen. It would work to keep snow off the wood though.
Similar here; in a typical year everything freezes solid by early December. The pallets that I mentioned above did their drying last year in Sept-Oct, but, losing 10 percentage points is not too shabby.
 

Woodsplitter67

Minister of Fire
Jan 19, 2017
2,036
Woolwich nj
This makes me giggle, because it's totally climate dependant. You might knock a percent or 2 off softwood in a winter here with that method, but it's pretty hard to dry wood when its frozen. It would work to keep snow off the wood though.
Yes this is not for everyone, and obviously someone in the Yukon won't benefit from this in the dead of winter. That being said this setup will work for many people in the lower 48 that are short on wood and could have wood ready for the end of the burning season, and also for someone in a cold climate it will start the drying earlier then just letting it sit on a rack.
 
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Poindexter

Minister of Fire
Jun 28, 2014
2,429
Fairbanks, Alaska
@Woodsplitter67 I don't remember when I first saw someone here doing this, or what their user name was, but I have been looking forward to more data since before 2020. From the beginning I have suspected these will work well, and they can be handled with forks which is awesome.

I am not clear if laying a sheet of plastic on the pallet before the wood goes on makes a difference, probably depends on how far off the ground they are and how wet the ground is.

I am (the nerd inside me is) a little concerned if the plastic is single use. It seems like a lot of plastic going to the landfill for one half cord of wood. I don't know the most ecologically efficient way to do it repeatedly, but I am not at all suprised to hear they work very well.

I don't get much moisture change in my kilns when the over night lows start getting below freezing. But I am at 64 degrees north latitiude, so limited sunlight in cold weather also. What I do see (in March) when my daytime highs are hitting the teens and 20s above I have enough sunlight and enough solar gain to get the green wood I stacked over the winter thawn out and then start pulling moisture out of it. By the time my snow is melted the fresh green standing timber from January that I stacked/kilned in Feb is below FSP, down to roughly 30%MC around May first when the raspberry canes start budding and most of the snow is gone.

I don't know why in general I see more action in the spring then I do in the autumn, except I generally go into autumn with dry wood and there isn't much more action to do.

Might check the air temp in there first thing in the morning a few times. As the water in the splits gets frozen you will be burning some daylight to get it melted every day before you can work on getting it out of the splits with your remaining daylight each day.

At some number of cords it would make sense to stack open sided palleted halfcords in a greenhouse rather than wrap them individually, but don't be poking the forks on your telehandler through the glass.

Somebody could build a what they call a "polytunnel" in the UK. Nice firm floor under it, wide enough for palleted half cords over to one side, room for a pallet jack on the other side, overhead door at each end. Just load it up end to end, then pull seasoned wood from one end and add fresh green to the other. Or build it big enough for a forklift, right next to a barn, and batch process. Fill it with green, wait, unload the seasoned wood into the barn with a forklift, reload.
 
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clancey

Minister of Fire
Feb 26, 2021
1,730
Colorado
What I cannot understand being out of touch with your way of doing things---why not buy one of those storage units that kiln dry and store wood and you can hook it up to electricity and have your wood drying and getting ready for use...They cost 1000 or more but I bet they are well worth it..old clancey
 

Woodsplitter67

Minister of Fire
Jan 19, 2017
2,036
Woolwich nj
What I cannot understand being out of touch with your way of doing things---why not buy one of those storage units that kiln dry and store wood and you can hook it up to electricity and have your wood drying and getting ready for use...They cost 1000 or more but I bet they are well worth it..old clancey

The object is not to spend the thousands of dollars on a kiln and thousands more in fuel trying to dry it. Many here like to keep their footprint small. Spending this kind of money also defeats the savings of providing your own fuel. I dont need to do this as I am sitting on 14 cords CSS, I am also not willing to give up my wood for others. I am putting this together for my own benefit to see if I can speed up the drying process over the fall, winter, early spring. I will be selling this wood at a premium. I am not a wood seller, this is not how I make a living. I am just helping someone out. Most people selling wood in my area are already out. The people selling wood are asking alot, up to 450 a cord for a mix of white oak and cherry, which is what im selling. I do things like this to see if it works and if I ever get jamed up in the future I have the answer. I also do this to post results and to help others, because we all know many of the new people could use some help. I helped my neighbor one year with a kiln and got him 3 years ahead..
 
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jaoneill

Feeling the Heat
We burn 10 plus cord a year and I began this experiment as one to limit the physical handling aspect of wood gathering. We have been heating with wood for over fifty years. As I age and physically slow down, together with being unable to hire help at almost any price, I was looking to minimize the handling of the fuel. My method came down to mechanizing as much as possible. Skid logs out to a central landing, utilize a FEL to hold the logs up at a comfortable height to block them up, then place splits directly on to pallets from the splitter, 1/2 cord per. I found that the stacks on the pallets would "loosen-up" as the splits dried and shrunk in size, requiring that they be secured before moving, which I did with ratchet straps, a PITA at - 20 degrees. Then about 15 years ago we switched to a gasification boiler that really likes its fuel at 10%, is ok with it below 15%, is unhappy with 20%, and rebels at 25%. This made my historic, annual routine, that resulted in 20%-25% fuel, unworkable. Building storage for 2-3 years worth of the volume of wood we burn wouldn't be cost effective, at my age I probably would never see a return on that investment. As much as I hate the waste, I minimize the plastic by using 4mil to top and 18" shrink wrap that serves the dual purpose of enclosing the sides and securing the splits for moving the pallets. Splits come out, depending on species, and elevation on the pallet, at 8%-15%; the Biomass boiler loves it. Re-using the top poly doesn't work, it gets too brittle; anytime I've tried it I have had to replace it after the second or third windy day rips it off. I use older pallets on the ground under the ones I'm stacking directly onto; better air flow under/up through stack and much easier to get the forks into when it comes time to move it.
 

all night moe

Member
Nov 19, 2015
73
earth
In theme of assisted drying, I had an idea last winter while siting in front of the wood furnace. I envisioned using a baker's cooling rack 3'x3'x6'H. I thought of enclosing it with sheet metal with a door on the front. Drilling a series of holes on the top, and putting a air inlet at the bottom for some forced air off the furnace. The racks could probably hold about half a face cord. Using the heat from a furnace or shop stove, the hear isn't wasted.

I post this in hopes this idea of mine, which I seem to be full of, may benefit someone.
 

stoveliker

Minister of Fire
Nov 17, 2019
1,922
Long Island NY
I've done a similar thing. I have a basement stove, and a register, duct, and fan sucking cold air from the floor of the living room, and depositing it on the floor of the basement. (Warm air then goes up the stairs into the main floor.)

I have directed the fan to stacks of wood near the stove that was marginally dry. It's not hot air, but it's near 70 f, a constant stream, and quite dry (winter, after all).
 

Woodsplitter67

Minister of Fire
Jan 19, 2017
2,036
Woolwich nj
@Woodsplitter67 I don't remember when I first saw someone here doing this, or what their user name was, but I have been looking forward to more data since before 2020. From the beginning I have suspected these will work well, and they can be handled with forks which is awesome.

I am not clear if laying a sheet of plastic on the pallet before the wood goes on makes a difference, probably depends on how far off the ground they are and how wet the ground is.

I am (the nerd inside me is) a little concerned if the plastic is single use. It seems like a lot of plastic going to the landfill for one half cord of wood. I don't know the most ecologically efficient way to do it repeatedly, but I am not at all suprised to hear they work very well.

I don't get much moisture change in my kilns when the over night lows start getting below freezing. But I am at 64 degrees north latitiude, so limited sunlight in cold weather also. What I do see (in March) when my daytime highs are hitting the teens and 20s above I have enough sunlight and enough solar gain to get the green wood I stacked over the winter thawn out and then start pulling moisture out of it. By the time my snow is melted the fresh green standing timber from January that I stacked/kilned in Feb is below FSP, down to roughly 30%MC around May first when the raspberry canes start budding and most of the snow is gone.

I don't know why in general I see more action in the spring then I do in the autumn, except I generally go into autumn with dry wood and there isn't much more action to do.

Might check the air temp in there first thing in the morning a few times. As the water in the splits gets frozen you will be burning some daylight to get it melted every day before you can work on getting it out of the splits with your remaining daylight each day.

At some number of cords it would make sense to stack open sided palleted halfcords in a greenhouse rather than wrap them individually, but don't be poking the forks on your telehandler through the glass.

Somebody could build a what they call a "polytunnel" in the UK. Nice firm floor under it, wide enough for palleted half cords over to one side, room for a pallet jack on the other side, overhead door at each end. Just load it up end to end, then pull seasoned wood from one end and add fresh green to the other. Or build it big enough for a forklift, right next to a barn, and batch process. Fill it with green, wait, unload the seasoned wood into the barn with a forklift, reload.

The plastic is recycled from other projects and is on its last leg. I have cut them down to 7x8 size and will use them till they fall apart. I have often thought about the hoop house and just basically baking the wood late spring/summer/fall. I know that this will work. I dont have the space and since I dont ever need that much wood, its not for me. I see the same as you. my greenhouse gets way warmer in spring then fall and early winter. As soon as late February early March rolls around it gets extremely warm in there.

I tested the wood yesterday. The larger splits went from 36/38 to 28/30 and the smaller stuff like 3 inches are down to like 10% from the 30s.. not bad for 60days of drying in fall weather its not very uniform as the pallets need to be turned because the sun angle is low and the back side isn't heating up like in summer time. This is what you learn..

20211126_155921.jpg
 
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clancey

Minister of Fire
Feb 26, 2021
1,730
Colorado
Gosh you people have some good ideas especially since a lot of the ways you are reusing energy that would just go off into the air (forced air furnace and heated air with fans blown that way to dry the wood out)--wonderful --and if you need it now--you have it instead of rotating the wood piles for three years...Now for me since I do not use it a whole lot but must admit addicted now I am checking into the different types of kilns so that I know my wood will always be dry...My kiln dry wood is registering 10 or 11 moisture but my mixed advertised as seasoned is measuring 18 % and it is definitely harder to start as well as to keep it burning but I am new at this and will look at pretty pictures of different kilns...lol clancey
 
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