The Forestry Forum

General Forestry => Drying and Processing => Topic started by: fluidpowerpro on October 17, 2022, 01:30:30 PM

Title: Would like feedback on feasibility of building small bench top kiln.
Post by: fluidpowerpro on October 17, 2022, 01:30:30 PM
I recently sold some 4/4 kiln dried red oak to a small manufacturer of specialty items.
I only own a sawmill so I had to take the wood to an outside source to have it dried.
When delivering the wood I learned that all of their boards get cut to 2 ft lengths before they run it through a planer. It then gets cut into 2" wide strips before further processing.
I also learned that in the past 12 months, they have only used 600 bf. If they double that in the next year they will be happy so in summary, they dont use a lot of wood...
Considering all of the above, I was wondering if it would be possible to build a small bench top kiln so I could dry it myself. I'm imagining an insulated chamber with a heat source and fan. I'm located in northern MN so I'm thinking that if I only dried the wood in the winter, the low humidity would make this possible.
Is what I'm thinking feasible or am I on drugs?
Any feedback will be appreciated.
Title: Re: Would like feedback on feasibility of building small bench top kiln.
Post by: Crusarius on October 17, 2022, 03:00:34 PM
I have thought about the same thing. I have no idea if it will be lucrative or not but sure would love to hear from some of the experts here.
Title: Re: Would like feedback on feasibility of building small bench top kiln.
Post by: barbender on October 17, 2022, 03:46:00 PM
That Suano kiln that Logosol sold for a while just used foamboard for a chamber. I sure don't see why you couldn't use something like that with a small dehumidifier (knowing that it won't live a long life) and whatever small fans you need for air flow. My main concern was the fire danger of actually having it in the basement.
Title: Re: Would like feedback on feasibility of building small bench top kiln.
Post by: Don P on October 17, 2022, 04:02:36 PM
That's why we did it in the garage, it'll work.

I can hit 8% in the living room during heating season. We did one job that had a sauna in the basement. I broke that unit in as a wood kiln  ;D.
Title: Re: Would like feedback on feasibility of building small bench top kiln.
Post by: bigblockyeti on October 17, 2022, 04:57:43 PM
Selecting and Drying Wood had several ideas including the construction of a dehumidification kiln written by William Bolf where he built a kiln for his basement that would hold up to 250bdft.  It's a good read despite being a rather old article (1991) as everything he used is still relevant and available today.  He did mention it won't get hot enough to dry resin pockets but he was only intending to sterilize and dry domestic hardwood so that also made it safe to keep and operate in the basement.
Title: Re: Would like feedback on feasibility of building small bench top kiln.
Post by: Walnut Beast on October 17, 2022, 05:11:59 PM
Maybe crazy but a old electric oven, dehumidifier and fan come to mind, side cut out of oven for box with dehumidifier and fan 😂 or a Sunheat heater for a heat source with fan and dehumidifier 
Title: Re: Would like feedback on feasibility of building small bench top kiln.
Post by: doc henderson on October 18, 2022, 06:56:17 AM
what volume do you anticipate wanting to dry at a time.  In the winter, you can just use heat, and vent into your shop if it is dry and warm already.  I have done very small items in my blanket and fluid warmer I got from a hospital.  goes 160.  I have done thinner stock just in the shop with fans.

drying thin wood for coaster stock. in Drying and Processing (forestryforum.com) (https://forestryforum.com/board/index.php?topic=116232.msg1840488#msg1840488)


(https://forestryforum.com/gallery/albums/userpics/51041/A52DD945-2F9F-42B0-AEA5-DC2F909D1F6A.jpeg?easyrotate_cache=1664285179)
 
(https://forestryforum.com/gallery/albums/userpics/51041/C6AE0BB3-7CE9-4CF1-9E2B-F3BB5D8D8041.jpeg?easyrotate_cache=1666091138)
 

dropped 4% over night to 7%.  charcuterie boards for a young lives' charity.
Title: Re: Would like feedback on feasibility of building small bench top kiln.
Post by: doc henderson on October 18, 2022, 07:07:54 AM
I am about to build a temp hot box with pink rigid foam.  I need to finish off a walnut mantle.
Title: Re: Would like feedback on feasibility of building small bench top kiln.
Post by: tule peak timber on October 18, 2022, 10:03:11 AM
Doc's idea will sure work! A pic of an old water heater thermostat that I've used on a hot box. Be careful with the extruded styrene (pink/blue board) to not get too hot as it will deform. Polyisocyanurate (ridged urethane) board can take higher temps. This is the board, typically with a foil covering, and around the same price as the styrene. You can use things like toothpicks or pencils to pin the box together or silicone bathtub caulk. If you disable a small electric room heater, add some vents, maybe even a fan, you have your benchtop kiln. Don't get me wrong, I love my Nyle L200 and it runs pretty much 24/7/365, but there are times when I am doing some oddball thing, like giant tree branches or really small stuff that a hot box is the way to go. To finish off at higher temp, for sterilization, think outside of the box (pun intended) and turn to the wife's oven! We would be interested to see what you come up with. 
(https://forestryforum.com/gallery/albums/userpics/35190/thermostat.jpg?easyrotate_cache=1666101681)
 
(https://forestryforum.com/gallery/albums/userpics/35190/oven.jpg?easyrotate_cache=1666101720)
 
Title: Re: Would like feedback on feasibility of building small bench top kiln.
Post by: doc henderson on October 18, 2022, 11:13:49 AM
the Owens (pink) foam is rated to 165° F from what i read.  and I have some.  some use the halogen lamps.  some of the room heaters have a high temp shut off.  I love the thermostat idea.  glad you are back Tule!
Title: Re: Would like feedback on feasibility of building small bench top kiln.
Post by: Andries on October 18, 2022, 11:28:52 AM
Tule; is that an epicormic glaze on that butt-ugly roast ? 😁
Good to have you posting again!
Title: Re: Would like feedback on feasibility of building small bench top kiln.
Post by: tule peak timber on October 18, 2022, 11:37:52 AM
Nah,,It is a sycamore backstrap in need of a polyurethane basting  :D 
Title: Re: Would like feedback on feasibility of building small bench top kiln.
Post by: barbender on October 18, 2022, 11:57:22 AM
Also, be ready for the shock if you go to buy foam board now😬
Title: Re: Would like feedback on feasibility of building small bench top kiln.
Post by: Don P on October 19, 2022, 03:32:26 PM
Yeah, I need 100 sheets for work, it ain't pretty. I guess about 10 years ago I remember $26/ 2" sheet on a job.
7/16" rated OSB was $14/sheet here last week.

We were using landscape ground staples and welding rod pieces, both make decent foam construction pins. Then we shot it together with a few cans of sprayfoam. Uhh, to be honest that is why I don't get into kiln door construction threads, on the big DH kiln, we shut the floppy doors and blow a can :-[ :D.
Title: Re: Would like feedback on feasibility of building small bench top kiln.
Post by: doc henderson on October 19, 2022, 04:32:24 PM
i have been looking at heating element kits for electric clothes dryers on amazon.  come with the element, ductwork, thermal limits and fuses.  If you want a serious one that kicks off at 165 and back on after it drops 25 degrees.  i will let you know.  i really did not want it to me a 220V unit just for convenience.  they run about 39 bucks.
Title: Re: Would like feedback on feasibility of building small bench top kiln.
Post by: aigheadish on October 20, 2022, 08:11:52 AM
I am interested in this idea as well, and my post asking about it in the other thread can be ignored. 

I have a shed, that I planned to use as a kiln, once my barn is finally done and I move all the junk out of it, but that'll be a big, expensive job for something I may not use much of. A smaller more mobile unit sounds like a better plan and maybe I could just store and run in it the shed rather than seal up the whole thing.