Mini Drying Kiln Design????

[mredden]

Does anybody know of a design for a kiln that would only dry about two 9/4" x 36" x 96" live edge boards at a time?

I would like to have the ability to pull one or two boards out of my air drying stacks - when ordered by customers - and take them down to the moisture content of the customer's home (or porch) for countertops and kitchen islands.

The length kinda eliminates old freezers and pizza ovens : so I'll have to build something. Thinking probably solar/dehumidifier combination.

Suggestions other than mental health counseling?

[farmfromkansas]

The size of boards you are drying makes me think of a solar kiln. Capacity would be about right, and you can add a dehumidifier.

[barbender]

That small, I would think you could make a box out of foam board insulation and a dehumidifier.

[YellowHammer]

Are you planning to sterilize?  

[Crusarius]

I started a thread asking about using a steel pipe to make a small kiln. I just got a lead on steel  pipe that is being removed from under the road today. Probably 5' diameter. 

My thought was to cut the pipe in half so it is only a half circle. This will remove the rotten section of the pipe. Then build an insulated floor for it, and place it on an angle that should allow natural convection to circulate the air. Paint it all flat back and put some gauging in it to monitor temperature and humidity.

Not sure how well it will work but it could be a pretty low cost option. At least something fun to play with. If it doesn't work it can be turned into a spillway for the pond or something.

[mredden]

Are you planning to sterilize?  

Yes, I will need to. Powderpost beetles are a problem in my area, and they seem to really like pecan - that I am cutting a lot of.
Solar in South Georgia should generate a great amount of heat in the many sunny, summer days of 95+ degrees, but I realize I will probably need to boost with an auxiliary heat source when the sun is not on the panels. Your advice would be greatly appreciated.
My air-drying stickered stacks have borox on and around them. When I get log opportunities that I can't get to for awhile, I borox the ground and roll the log on top of it. It has kept the termites out - so far. Haven't seen any carpenter bees around.
I have a lot of learning to do. That's why I am asking for help.

[btulloh]

That small, I would think you could make a box out of foam board insulation and a dehumidifier.

I agree with this. Simple, cheap, easy and fits this specific job.  Dehumidifier will supply enough heat for drying.  A heat lamp or two should provide enough heat for sterilization.  Caution when adding heat.  

[K-Guy]

Several years ago, I saw a chamber like that using a fan and dehumidifier in a wood working magazine but you couldn't sterilize with it. This type of setup will probably be your best bet but you will have to take it to someone with a big kiln for sterilization or chemically sterilize it.

[GeneWengert-WoodDoc]

Does your house or garage have an attic.  This is where I dried my lumber...a few boards at a time indeed.

[YellowHammer]

I'd probably build an insulated box and put in a dehumidifier some fans and a couple heat lamps.  

[mredden]

Does your house or garage have an attic.  This is where I dried my lumber...a few boards at a time indeed.

Yes, I do and it's one big, hot sumbisk - especially during a South Georgia summer. It even has an old attic fan that I might be able to move to the eave vent and get working.
I might have to enlarge the smallish access (and eat my wheaties!) to get these wide slabs up there, but that's a great idea! Oh well, I had been considering access enlargement anyway.  Heck, I can put a block and tackle up there too.
I guess I might double down on the boric acid when I take them up in my attic just in case there are hidden critter eggs. I have heard that attic temps get into the 150s around here under a dark roof like mine. I wonder if I can keep that up at night for long enough to sterilize?
The expert comes through!!!!!!! Thanks Doc! 8)

[YellowHammer]

I like to put a lot of weight on mine, it really makes a difference on how flat the slabs will stay.  Just like drying any wood, the first couple layers on the stack aren't constrained and do what they want unless weighted.  Slabs are generally pretty ornery. 

I put about 3,000 lbs on mine to keep them flat. 

 

[doc henderson]

I have done this a time or two esp. with big slabs.  I build a kiln with plastic in place.  watch you tube video call simple solar cycle kiln by timbergreen.

[doc henderson]

 

 

9/4 and 10 feet long, mostly air dried, plane out nice both sides flat, 7/4.  Elm live edge, it was gray when I got the log. rustic.   MC about 17%

[Bruno of NH]

What about a black plastic culvert pipe
4' dia. Cut on half on the mill.

[LeeB]

That stuff is a little pricey.

[mredden]

I have done this a time or two esp. with big slabs.  I build a kiln with plastic in place.  watch you tube video call simple solar cycle kiln by timbergreen.

How it work in very humid areas? I'm gonna try it this summer, but I'm slightly worried about mold. Perhaps the heat will keep it down.

[doc henderson]

you can start with air drying and then only use this to get below 12% and or to speed things up.  Even with high humidity areas, if you raise the temp inside a kiln, the relative humidity drops.  As the temp goes up, the hotter air can potentially hold more water in the form of vapor.  That is the definition of relative humidity, what is the amount of water in the air, relative to the total amount it could hold at a given temp.  At night water will condense and run down the plastic.  often even if wrapped, the sides are left open for the first few weeks.  This is a compromise to a formal well insulted, monitored and fan powered solar kiln.  Most schedules want the beginning humidity in the kiln to be high depending on species and thickness.  if it is air dried, this is less significant.  @GeneWengert-WoodDoc 

[doc henderson]

Where are you in the country.  you can look up your average humidity and predict you final MC from air drying.  If this wood is ultimately going in a house, then you will want to go lower.  The foam board with a dehumidifier will work.  This plastic cover will generate lots of heat, but not for long periods since it will drop at night, since these are thick slabs.  I also put a couple 20 inch box fans inside once.  I also got a accurite temp and humidity set, with a part that goes into the kiln, and a monitor that can be 100 feet away like in your shop.  If you would want to fill in your profile info, Dr. Wengert can help with final MC in your area, and has a general rule for drop in relative humidity for a given raise in temp.