Drying for heavy hobby / very light business use

[Mr. Buck]

Hi all, 

I make custom furniture and do some niche work for churches (carvings, certain more unusual furniture), so not large volume. 

I've purchased a Woodmizer LT35 and I have access to 60 acres of primary (for furniture) woods such as poplar, oak, cherry, walnut, hard maple, etc.  I may use 2-3,000 bdft per year.

In my area, it's nearly impossible to pay someone to kiln dry lumber for me for reasons. 

I need a solution to dry and sterilize my own lumber in small batches as inexpensively as I can while still doing a reasonably good job.  I need something that doesn't need to be installed inside a building (not counting the chamber), preferably doesn't require a cement slab, and can dry maybe 3-500 bdft. 

Can anyone recommend a "starter" solution that's easy, does a good job, but is just small?  Is it realistic to do for something like $10k all in (including pre-requisites)?

[rusticretreater]

The Virginia Tech Solar Kiln is a low cost solution.  I know a fella who uses homemade arches and thick plastic sheeting to make a tunnel heated by solar.

A 10K budget?  Yeesh, get a shipping container and have at it.

[Ianab]

The VT solar kiln is basically designed for this use case. Need kilned dried lumber on a budget? While it has limitations, especially in Winter, it's cheap to set up, cheap to operate, and works. If you need to expand beyond "hobby" level you can buy a container / DH based kit, and ADD that to your operation. But as you have a sawmill. you can cut much of the material for the solar kiln for little cost. 

[KenMac]

I don't know the current price, but the Nyle L53 would suit your requirements very well I think.

[doc henderson]

4500 bucks.  they are a sponsor.  go to the kiln store on their website.

[barbender]

Nyle has small units which I have been considering, and Idry (also a sponsor) recently came out with a unit that can bolt on to a container.

[YellowHammer]

L53 is a very, very good kiln for the price. 

[Mr. Buck]

I have considered building a solar kiln as I live in the south (I have the plans), but I'm concerned I can't get it to sterilization temps in the winter.  I will need consistency. And I really can't wait 90+ days to dry a batch. 

I'll look into all of the options suggested. Thank you very much for the replies.  If anyone has tips on how to buy a shipping container, I'd love to hear it. I have no idea where to start. 

[Magicman]

Google search is your friend. 

[doc henderson]

MM is right, a google search will show all the sites that sell containers within so many miles.  we have one here that also sells Sturi-built sheds.  they deliver and place it where you want.  If you want to paint it black and put a DH unit in, it will work ok.  A Nyle unit will last longer and have better control, and likely a more powerful compressor. 

The solar stuff works and is simple and cheap to build.  with night relaxation of the stress, it is easy to dry many species. 

A hot box can sterilize but needs to be well insulated with heat and moisture tolerant materials (closed cell foam or rock wool insulation) and can be powered with halogen lights or a wood furnace or stove.  A solar kiln is well insulated ideally, except for the glaze material.  so, it is hard to make a solar kiln that you can sterilize in.  A compressor may shut down in a DH kiln with a temp of 160.

Some people use a container that was used for refrigerated items and is insulated.  You must check the heat rating or type of material it is insulated with to see if it tolerates heat.  also, it needs to be resistant to moisture.  If there is a skin, it needs to be resistant to the chemicals in water from fresh lumber especially oak. 

I use a 20-foot container with a DH (70 pint) and 3 twenty-inch box fans from WM.  I maintain more than I dry, but 300 to 500 BF would prob. be OK.  I have more in it than that, but it is mostly dry already.

I want a solar kiln as it is faster than airdrying with more control.  It is also faster than a conditioned room at 70 degrees and the humidity can go higher to start slow until the wood is at a safer drying MC.  I have plenty of wood in my shop and it gets to 7% but it may set for 2 years without a plan.  I also have a fluid and blanket warmer sold at auction from a Military hospital.  It goes to 160 but is only about the size of a refrigerator.  I have sterilized little bits up to 3 feet long overnight.
 
I priced having a heating and air place make me a hot box using galvanized sheet metal and duct insulation with doors at each end.  It was a thousand bucks and was 4 x 4 x 8 feet to sterilize small loads.  I bought replacement dryer heating elements with all the safety heat fuses etc.  About 23 bucks on Amazon.  I decided not to but still have the plans if I feel the need to spend money.  If you have a buddy in the industry, I am sure it can be done cheaper.  that was a few years ago, so not sure what the metal and labor prices have done. 

You could do solar or build a hot box the size you need most and you can dry and sterilize in the same container.  In the winter get the heat up to 100 or so and run a dehumidifier.  or get the L53 and follow their plans.

I have thought about putting moving blankets on top of the solar kiln glaze for insulation for a heat treat cycle, but plastic fans and glaze may deform if it gets too hot.  let us know what you decide.

[scsmith42]

Lots of good advice thus far above.

 If I were in your shoes, I would look at building a very well insulated solar kiln with auxiliary heat for sterilization.

 I operate both solar and nyle dehumidification kilns, and the benefit of solar for your application is that you can safely mix and match different species, thickness, and moisture content in the solar kiln and you don't have to worry about overdrying them. 

In a dehumidification kiln you have to pay more attention to the drying process than having your kiln loaded with similar species, fitness, and moisture content.

Bottom line, solar is more forgiving and easier to operate for a novice.

[YellowHammer]

I've had both a solar kiln and an L53 operating at the same time, I called the solar kiln the Easy Bake Oven of kilns.  it gets hot in the summer, but I never considered wood coming out of it sterilized.  However, in the winter, I used a cheap WalMart 60 qt dehumidifier and that worked fine, bit I did vape to replace them every couple years.  They had a drain line and I just routed it outside.  How do I Know it won't sterilize?  I finally tor hit down after decades of work because it had mice in it, and I couldn't drive them out with the heat.  However, it cost pretty much nothign to build because I built it with sawmill lumber, used cheap fiberglass insulation and cheap plastic roof glazing from the big box stores.  The only time I had to replace the plastic roof (two layers) was after a big hailstorm.  I built mine small enough where I could pick it up and move it on the forks of my ladder, or certainly skidded across the ground lie a garden shed.  Actually, a solar kiln is nothing more than a garden shed with a single 45 degree roof.  You could run heaters to get to sterilization temps, some people use blower heaters.  I would dry the wood with it, and then forklift the pallet of lumber into one of my other kilns to do the sterilization cycle.     

An L53 is more of a "real kiln" with electric controls, WB/DB and stuff like that, and is also a kiln that can damage your loads, but can sterilize. I use it as my "small batch" kiln and consider it vital to our operation.  One of the members here built his with a wooden floor and it produced excellent lumber.  Mine is on concrete, it does not take much, a 10' x 10' or so pad, and I think that is best.  Of course, a 10x0 concrete pad can be poured easily with one person, and removed with pretty much any tractor or such if you want to remove it.  Typically, you will need to install extra heat and extra fans to get it to operate optimally.

Both kilns are good, but for our business, I torn down my old solar kiln and still run my L53.  I'm on my second, just replaced the compressor on it, and it's got maybe $15,000 of walnut live edge in it right now, so you know that I trust it with my high dollar wood.        

[rusticretreater]

If anyone has tips on how to buy a shipping container, I'd love to hear it.

They are often listed on craig's list under trailers.

[YellowHammer]

If you are going to get a shipping copartner for a kiln, it must (should) be a high cube reefer, stainless and aluminum, as the normal shipping containers rust out pretty quick.  Just Google "shipping containers near me", and big distributers will show up in your nearest big city, and they will have them delivered to you generally through the nearest shipper. 

[Ianab]

Shipping containers get replaced Before they get too beat up or rusty to be usable, and while they can still be sold off for more than scrap prices, and repurposed. Heck, locally people buy several and make then into a house. Or they make an instant lockable shed around the farm etc. 

Last time we were in Rarotonga the locals were refurbishing an old hotel site that had been abandoned for decades. As it was 2 story they would have needed scaffolding to work on the outside / roofs. Expensive to import. Instead they just put shipping containers around it, and used those to work off. 

With the right contacts at the shipping company they could arrange for regular freight to come in an "expired" container, and save the expenses of sending it back empty. They will probably have rusted out by they time they finish the project, but they will have served their purpose. 

[Brad_bb]

Do you need a concrete slab in order to be able to weight you stack properly?  Would a wood joist floor flex too much? or not be able to handle the weight?  I know Yellowhammer uses thousands of pounds of granite slabs.