Author Topic: Solar dry kiln construction (Read 8785 times)

Planman1954 · « **on:** April 13, 2011, 07:44:01 pm »

Hi all.
   This thread may be a bit premature, but I'm excited about a solar drying kiln that I'm about to start on. The design will be based on pineywoods design. His solar kiln heats up during the day to 160 degrees and cools down at night. This allows the wood to dry with less wood stress, avoiding splitting.
   I plan on making the kiln about 5' wide x 18' long, and bolt on an axle and tube for a hitch that my Norwood lumbermate uses so that I can tow it around the yard. I also plan to have the door panels made in sections that are easy to remove...and possibly hinge one on the end for easy in and out access during the drying process.
   I cut out all the pieces last week out of SYP so it can dry for about a month before I start the assembly. The only big expense will be the translucient panels for the top. I'll post start to finish pictures when I get started in a few weeks. I'm pumped!

Jasperfield · « **Reply #1 on:** April 13, 2011, 08:56:34 pm »

If it turns out as well as did all of those doors that you made, it should be pretty nice.

WDH · « **Reply #2 on:** April 14, 2011, 07:51:42 am »

I am really interested in this as well, so I look forward to your experience. I saw the Pineywoods design, and it is different in how the solar collector is designed (say versus the Virginia Tech design), so that might explain how he gets a much higher temp than others can achieve.

Bill Gaiche · « **Reply #3 on:** April 14, 2011, 08:21:09 pm »

Planman1954 , I plan on starting my kiln in about 30 days. Have had loblolly pine cut for about 3 weeks. Mine will be 6' x 12'. Have bought and recieved 2 gable vent fans for air circulation. Like you said the plastic covering isnt cheap. About $28.oo at Lowes for 12' x 2'. The treated plywood isnt exactly cheap for the interior either. What kind of siding are planning on doing? Good luck and do some good photos as you go. bg

Planman1954 · « **Reply #4 on:** April 14, 2011, 11:28:11 pm »

10-4 Bill.
Here's a couple of pics of the lumber I'll use:

The top pic starting from the right are some 6"x6" cross members for the base beams. Next is 3"x6" stock that I will laminate with bolts and large nails to make the long 6"x6" support beam. Next are 2x4"s for the floor joists, top and bottom plates, and upper rafters. Next are 1"x12"s for the floor. (I wish I had cut them 3/4" thick since they will bear no weight...only keep air in.) Finally, sort of out of the picture, are some 3/8"x8" boards for the interior walls, and 8" lap siding for the exterior. The bottom pic is some 2x4s for the walls, some 1x4s for the door frames, as well as some more siding and interior boards. I think you'll see it all come together when I start the build around the middle of May. Take care.

pineywoods · « **Reply #5 on:** April 15, 2011, 10:24:05 am »

Planman came visiting and measured, sketched and looked over my kiln. He got it, this thing is nothing but a chicken coop with a plastic roof . His should be an improvement over the original in several ways. Added length will allow drying 16 ft lumber. I welded up my door frames out of 1 inch square tubing, he has figured out a way to make doors from free wood. Planman's location is just about ideal from a solar standpoint, top of a bare hill with un-obstructed view to the south. His place is about 4 miles from me, so I plan to make a pest of myself when he starts construction.

Bill Gaiche · « **Reply #6 on:** April 15, 2011, 11:53:40 am »

pineywoods , He may very well put a hammer in your hands so you may not be the pest of the neighborhood that you claim to be. I am going to pick up some treated plywood today for the interior, 1/2" @ $15.00 per sheet.
Planman1954, looks like you have good start on the lumber. bg

WDH · « **Reply #7 on:** April 15, 2011, 08:20:55 pm »

Maybe the Grouchy Old Men will make an appearance

.

Fil-Dill · « **Reply #8 on:** April 15, 2011, 08:42:27 pm »

Are you using the attic vent fans only. I picked up 3-12" all metal fans today at Orshlens and they are 3 speed and cost 24.99 each. I have one in my shop that has ran for years at 8 hrs a day. I wondered if anyone has tried them in a kiln where the temp. will be higher. They also carry a 16" , 3 speed for 29.99 each.

Planman1954 · « **Reply #9 on:** April 17, 2011, 12:26:23 am »

Fil-Dill:
I plan on using 1 or 2 simple box fans mounted facing down, just as pineywoods has done. It works well. If one dies, I'll get another. They're cheap!

Woodey · « **Reply #10 on:** April 17, 2011, 09:54:01 am »

How do you get the temp. up to 160 degrees during the day ?
I would to know more about the pineywoods kiln system.

Fil-Dill · « **Reply #11 on:** April 17, 2011, 07:44:10 pm »

Do you think I can get by with vinyle siding on the outside? It is grey and I have alot of it around.

pineywoods · « **Reply #12 on:** April 18, 2011, 10:39:55 am »

Vinyl, wood, old roofing metal, construction board, plywood etc. Just about anything will be fine for siding. It's nothing but a small building with a south-facing clear plastic roof. What's different from other designs is the amount and placement of the metal collector panels. Wood is a lousy solar collector. What you need is metal painted flat black. fastening the metal to the bottom of the rafters has 2 advantages. 1. more room to install more collector, about 50% more. 1.. The collector is perpendicular to the suns rays which ups the effeciency considerably. There's pics and drawings in my photo gallery.

pyrocasto · « **Reply #13 on:** April 18, 2011, 05:50:57 pm »

Metal collector is nice but not needed. I havent even finished mine and without the doors being painted black yet(about half the sunlight hits them) it already hits 160 sitting in good sun. As long as light isnt reflected back out anything will soak up the same amount of heat. The main heat loss in a solar kiln is the plastic/glass for the sun to come in. That's why doubling up on the glazing is suggested.

For mine to keep the price super cheap I used a green house plastic rated for 5 years. PVC corrugated panels yellow the same, so unless you use glass or fork up for polycarbonate the 6mill greenhouse plastic works just as good.

I've spent several years in DIY solar projects and my solar heating panels at home use a furnace filter for the collector, which actually works better than the metal collector I originally built.

Planman, have fun. It may get frustrating at times since it's a large kiln but it's always worth it. I have to tweak my doors, finish coating, add the fans, and I'll be done with mine.

Problems I ran into:
Trying to fix the doors too tightly. Put a door jam in and move along. The kiln will tweak back and forth with the weight of the huge doors.
Tar. I will never use tar again just because it's so nasty, takes FOREVER to dry, and gets nice an soft again every time it gets hot for a long time. I'd rather spend the money on a elastomeric coating and either tent it black or paint over top. At least then I can spray it on.

Planman1954 · « **Reply #14 on:** April 18, 2011, 06:41:12 pm »

Hey pyro....nice post. How bout a photo of your kiln? Also, i plan on doing the access area a little different than just large doors. You'll see...if I can figure out what I'm doing!! I will post photos as I go along. Pineywoods design dries wood in about 2 to 3 weeks. What do you think yours will do? Again..thanks.

WDH · « **Reply #15 on:** April 18, 2011, 08:34:41 pm »

Piney,

Have you dried much oak? Would 160 degree temps dry the oak too fast and lead to case hardening and honeycomb? I know pine can take it, but I am concerned about hardwood and oak especially as I cut 98% hardwood.

pineywoods · « **Reply #16 on:** April 18, 2011, 09:03:45 pm »

WDH that 160 deg figure is just a bit misleading. It does get that hot on a good sunny day, but it don't stay that hot. The average temp over a 24 hour period will be much less. Cools off to close to outside temp at night.How much it cools off is highly dependent on species and the size of the stack. That allows the wood to stabilize and moisture to migrate slowly to the surface. I ran a batch of 4/4 air dried pin oak (really water oak) through mine for about a month. Moisture meter said 6%. I made tongue and groove flooring from it, nailed it down to a plywood base, NO shrinkage. On the other hand, some 14 inch wide pine wall paneling did shrink a little after I nailed it up. When it comes to solar kilns, published drying temps and schedules are useless. One stack may dry ok in a month, the next similiar stack may take twice that long. There are just too many variables.

pyrocasto · « **Reply #17 on:** April 18, 2011, 10:12:49 pm »

Planman, I don't know about dry time since that varies a lot with load size, location, weather, etc. Looking seriously forward to putting a stack in it though. I'll try to get a couple pics up at work as my computer busted. Look forward to seeing yours.

Piney, do you adjust your vents much during loads or for different species? Hopefully my first bat h of 1000ft 4/4 maple turns out without any issues.

pineywoods · « **Reply #18 on:** April 18, 2011, 10:46:32 pm »

Quote from: pyrocasto on April 18, 2011, 10:12:49 pm

Piney, do you adjust your vents much during loads or for different species? Hopefully my first bat h of 1000ft 4/4 maple turns out without any issues.

There are no vents on either of my kilns. I use a cheap room de-humidifier running at night to take the moisture out.

thecfarm · « **Reply #19 on:** April 19, 2011, 07:55:47 am »

Plansman,we used box fans,at $10 each than,in our greenhouse for 3 years.They would run steady,24/7 from Feb-March until late June.Never burned one out.I told the wife,they won't last long. Sure was wrong on that.They are stored in the old farm house now.

Fil-Dill · « **Reply #20 on:** April 21, 2011, 09:52:37 pm »

Will you paint the interior black and if so, what with. I was wondering if the foundation sealer, softens up during the high temps. Flat black paint doesn't seem to be to common in larger amounts.

Planman1954 · « **Reply #21 on:** April 22, 2011, 07:51:56 pm »

I'm probably not going to paint the interior at all...except for the top of the galv. metal nailed to the bottom of the rafters. You'll get the idea when you see the progression of the construction...about 2 weeks away!
I do plan on staining the outside though to protect the wood from the elements.

Bill Gaiche · « **Reply #22 on:** April 27, 2011, 09:10:22 pm »

Fil-Dill, I priced some flat black paint made by Anchor Paint Monday and it was $26.00 per gal. Its made in Tulsa, Ok. You can buy directly from them. I bet they sell it also in 5 gal. buckets. The gal. I priced was at a metal selling company. Could be cheaper in Tulsa.
Set some concrete blocks today to support the four floor beams untill the rain put a stop to that. Hope to finish that tomorrow.
Plansman, what is going to be the heigth on the front side of your Kiln?

Planman1954 · « **Reply #23 on:** April 28, 2011, 10:00:16 am »

Probably about 8'. I'm not sure of the exact dimensions. The height will be determined by the length of the top plastic panels that I'll buy. I'll determine the length of the rafters first set on a 45 degree angle, then the finished width of the thing (around 5' or so.) It's only 5' wide since I'm putting an axle on the bottom to move it around. After I draw a section out full size on the floor of the kiln, I can then judge how high the thing will end up. Like I said, the front (or tall side) will probably be about 8' high, and the back side about 4'. I guess we'll all see when I get to it...been busy on some plans this week, and haven't been outside much.

Bill Gaiche · « **Reply #24 on:** April 28, 2011, 08:18:14 pm »

I started mine today. Got the blocks and support beams set. Constructed the bottom and will flip it tomorrow, insulate and add flooring. I believe I will go with 3' front or short side and do the back side however it comes out at a 45. Mine is 6' x 12'. I do a lot of figuring on the fly in the dirt. Didnt do a sketch, just build as you see it is my moto.

Fil-Dill · « **Reply #25 on:** April 28, 2011, 08:41:47 pm »

Thanks for the info Bill. I have my subfloor on, but am trying to figure out how to post pics. Mine is a copy of the Woodmagazine kiln. It is 8'X 18'.

Bill Gaiche · « **Reply #26 on:** April 28, 2011, 10:29:41 pm »

Fil-Dill, You bet, pretty good size kiln. Just keep working on the photo thing. bg

Planman1954 · « **Reply #27 on:** April 30, 2011, 06:01:46 pm »

Hello everybody.

Today I got started on rounding up some things to begin construction of the solar dry kiln. Bought some nails, ordered the clear plastic panels for the top, and went by pineywoods house. He did some metal working for me which will allow me to have a trailer base on the solar kiln so that I can move it around the yard.
I pulled an axle off of a wooden teardrop trailer project that I had abandoned a few years ago. It's on the left in the photo. The axle had been mounted under the leaf springs, so we removed the axle and put it on top of the leaf springs to get the kiln closer to the ground. The old bolts were tough, but with a little homemade bolt penetrator and pineywoods impact wrench, it didn't take too long! We also had to install some 7" long bolts for the new 6" deep frame.

The next thing we did was make a bracket out of some leftover steel. I'm going to bolt it onto the 6x6 base of the kiln over a slot cut out to accept the Norwood trailer attachment that's on the right in the picture above. Below is a photo of the bracket. It's 3" stock with 2 pieces 11" long welded to the top. Once the thing is in place, you'll get the idea of the configuration.

Hopefully Monday I'll post some pictures of the base assembly. Hope ya'll have a great weekend.

Planman1954 · « **Reply #28 on:** May 03, 2011, 07:09:44 pm »

Today I got a few free hours to start work on assembly of the base of the kiln. Remember that I'm making the base as a trailer to move around. I started by roughly laying out the side and end beams in order to level the 6 piers. The height of the beams from the ground is about 18" to allow me to install the wheels when I get ready to move the kiln around. The side beams will be two 3"x6" beams bolted together to get the length that I need of 18':

Here's a closeup of the axle bolted to the side beam:

Here's an end view of the progress I made today. There's still some more cross beams to fit and install, as well as some end pieces of 3"x6".

I'll hopefully be back on it this Thursday. Take care.

trapper · « **Reply #29 on:** May 03, 2011, 08:55:45 pm »

I beleive jason from wi built one on a wagon but I dont remember seeing pictures of it

Bill Gaiche · « **Reply #30 on:** May 03, 2011, 09:25:41 pm »

Planman1954, glad that you have got started. I have my south and north side up. Cut the rafters yesterday is all. The rain kept me from getting more done.
Cleaned up the boat and got fishing tackle ready to head to Lake Fork, Tx in the morning to do a few days fishing.
Excited to get kiln finished and see if it will suck the moisture out of some lumber. bg

1938farmall · « **Reply #31 on:** May 03, 2011, 09:58:37 pm »

here's something ? http://milwaukee.craigslist.org/mat/2353938473.html

Planman1954 · « **Reply #32 on:** May 04, 2011, 06:47:12 pm »

Aww...I thought my idea was original!

Anyway, I think mine will be a little closer to the ground and heavy duty than that one. I hope to be able to get 16' material in the thing. I plan on continuing working on the base in the morning. After the as-sem-bull-ly (as Norm Abram says) I plan on spray painting the base beams to protect them a little from moisture.

Planman1954 · « **Reply #33 on:** May 05, 2011, 07:36:23 pm »

OK. I worked all day and completed the base. It was a job for one fellow! I can barely type. Anyway, I got the sides and middle supports nailed and bolted together, and the front trailer hitch bracket installed (Thanks pineywoods. Looks like it might work well.) Here's a photo of the completed base:

I used 4 cans of flat black spray paint on all sides (and the entire bottom) of the frame. The next step is to put on the 2x4x16" oc floor joists. I plan on laying felt over the joists before applying the 1" floor boards. That will happen tomorrow or the next day. Stay tuned.

Planman1954 · « **Reply #34 on:** May 06, 2011, 07:25:41 pm »

More progress today:

First I nailed on the floor joists...2x4x16" oc:

Next I laid on a layer of felt to prevent air leakage through the floor:

And finally, the finished floor:

Next I'll lay out a section of the kiln on the floor full size so that I can determine the correct length and pitch of the rafters.

ljmathias · « **Reply #35 on:** May 07, 2011, 05:18:16 am »

Planman- looks fantastic and has got me itching to build one also.... as soon as I finish up a few little projects around the farm, I'll get started... in maybe a year or two. Isn't it frustrating that "things take time?" Friend of mine said once: TTT is the thing to keep in the back of your mind so you don't get frustrated, but man, you're going full steam on that kiln! Love the pictures- proves the old statement about a picture being worth a thousand words...

Lj

Planman1954 · « **Reply #36 on:** May 13, 2011, 08:05:38 pm »

Finally I have some time to work on the kiln tomorrow. I started on the long box beam that goes over the opening this evening, sort of a jump start on tomorrow. I used 3 pounds of nails on one side. Guess I'll start the day tomorrow at the store to buy about 4 pounds more. This is how many nails this one beam requires! Here's the link to the design I found on the internet:

http://www.apawood.org/pdfs/managed/Z416.pdf

(UPDATE: OK...it looks like this link doesn't work anymore unless you sign up to become a member) So...the beam is made from 2 18' 2x4's on the top and bottom with 2x4 blocks vertically. The blocks have to be in an exact position, so I guess you need to find another source for the spacing. Plywood is then nailed to both sides using a staggered tight nailing pattern about 1 1/2" apart as seen in the photos.

I'll take photos of it in the morning and hopefully post tomorrow's progress this weekend.Take care.

Planman1954 · « **Reply #37 on:** May 14, 2011, 07:39:21 pm »

Ok...here's photos from today's progress. First, I made the beam using the design of the website I showed before:

You get an idea of the nailing pattern required. It took me an hour just to nail one side of the 17'-2" long beam. It is also insulated with batt insulation.
Here's the first wall going up:

Here's the beam set in place. I did it myself by first lifting it onto some sawhorses set up on the floor, and then lifted one end up onto the supporting cripple studs, and then the other. I would not recommend doing this alone again. Get help.

The last photo is showing end of the day progress. I set one rafter on...it fit great! take care.

WDH · « **Reply #38 on:** May 14, 2011, 10:18:10 pm »

Once you get this one perfected, you can build another one (for me

).

pineywoods · « **Reply #39 on:** May 14, 2011, 10:27:49 pm »

WDH , maybe you didn't notice, but it's got wheels and a hitch

re, lifting the big beam...DanG knucklehead, I'm 4 miles away with a tractor with forks.

Looking good, looks like about the same dimensions as mine except for the extra length, that fixes one of my mistakes..

Bill Gaiche · « **Reply #40 on:** May 14, 2011, 11:34:49 pm »

Planman1954, looking good. Your progressing along real well. Are the goats doing quality control checks? bg

thecfarm · « **Reply #41 on:** May 15, 2011, 07:47:08 am »

If it's anything new they have to check it out if the goats are like the ones we had.

I did some work on the goat barn with them in there. They had to be right by my side,checking out my nails and tools. I finally had to lock them out to get anything done in a reasonable amount of time.

TexasHandyMan · « **Reply #42 on:** May 15, 2011, 10:50:55 am »

Have not posted much but wanted to share my use of a green house for solar drying. Purchased a greenhouse from Harbor freight fo $ 600.00 for my Mom , who moved in with my family during the winter of 2009 . She enjoyed flowers so I was trying to give her someplace to do it in the cold . Well she ended up passing away in about a month after erecting it . It sat for a year and I had already installed shelves and tables so alot of room was taken .The dimensions are 10 wide and 12 long. I stacked the pine cants onto the benchs and stickered. I set up boiler temp. gauges cause the cheap ones kept breaking. There are two vents on top always open and I was getting readings of !40 with them open . Have not closed them to get additional temps yet. But its nice to see that its still has a purpose even in the spring with the plants gone. Another note my Mom before passing suggested I get the sawmill .51 years old and she could still make me feal like I was 12. I purchased a Logmaster Lm-1 made here in Texas . The joy I get from making lumber is unnatural . I have a big smile on my face the entire time I making saw dust. Thanks guys for all your posts and teaching me so much lurking on your site . I hope I didn't ramble to much.

Planman1954 · « **Reply #43 on:** May 15, 2011, 02:09:50 pm »

Sorry about the loss of your mother. Its good to see you enjoying the greenhouse/solar kiln so much. That is inspiring.

ljmathias · « **Reply #44 on:** May 17, 2011, 05:27:20 pm »

And here I thought Planman was getting the goats used to being inside so we he fired it up for it's trial run, they would be there... and you get the idea: slow cooked at 160? Should work pretty good- nice and tender, smokey flavor. This thread has been entirely too long without mention of food.

So after we haul your beautiful kiln over to my place (I'm volunteering) for a first full load of wood to dry, do I have to block it up front and back to take the load off the wheels? Just checking in case it magically shows up here one day- that trailer hitch looks to be exactly the size of the ball on my truck.

Why don't I have a solar kiln yet? Oh, yeah, because I get distracted by other things to do...

Great job keeping us up to date on your progress, planman- thanks.

Lj

Planman1954 · « **Reply #45 on:** May 17, 2011, 10:17:13 pm »

I finished the back wall today...put the siding on the outside over felt...then insulated the inside wall...then put 3/8" thick boards on the inside to hold the insulation in place.

The last picture is me beginning to put insulation in the rear wall. More pics later.

TexasHandyMan · « **Reply #46 on:** May 18, 2011, 08:09:38 am »

Nice progress on Kiln . Great workmanship . I understand about your Goats . My wife is a Nubian Breeder . Milk and soap making , worth more than a meal .

Handy Andy · « **Reply #47 on:** May 20, 2011, 12:06:15 am »

If you were to put sheet metal under the rafters like on Piney's, you wouldn't really need to paint the inside black would you? Seems like you could just sheet it with about anything in that case. Or would the moisture cause waferboard or plywood to de-laminate?

Planman1954 · « **Reply #48 on:** May 20, 2011, 09:57:59 am »

Handy Andy:

You got it. The idea is to create a collector system between the rafter space with openings at the top and bottom for air to flow around the lumber. Therefore the light will not penetrate into the kiln itself...only a small amount maybe. So there is no need to have the inside black...it makes no difference. The metal is necessary to retain heat generated by the black paint. Check out a piece of metal that is black lying in the sun vs. a piece of wood painted black. The metal will burn you...the wood won't. So metal will be used painted black facing up under the rafters. You'll see how simple it is when I get to that point. I wish that I could have done it all in a few days straight...but I have to keep my income going with my REAL job...designing houses.
Oh, and I'll be using a dehumidifier set on the floor for a few days to take the moisture out of the air. This will prevent condensation under the panels. Pineywoods and I had a discussion about condensation, and I decided not to try to deal with it flowing downhill under the panels...just let the dehumidifier catch most of it.
Take care.

Planman1954 · « **Reply #49 on:** June 11, 2011, 04:42:28 pm »

Finally got some time to work on the kiln today. I got the exterior siding finished on the 2 ends. Then I ran wire for 2 outlets. One outlet is above the beam for the two upper fans I'll install, and one is on the end to plug in a dehumidifier. The inlet box is below the box on the far end wall. Here's a photo of the 2 plugs and inlet box:

Here's a photo of the inlet male 110 v. plug on the end. I can run an extension cord from my house and plug in the kiln for operation. I'll put a weatherproof cover over it after I stain the kiln.

Here's a photo of insulation being put in one end. Later I put 3/8" thick boards on the interior to hold the insulation in place:

I also got the interior boards on 1 end wall finished, started on the other until the heat made me stop. I started at 6 am and stopped at 1 pm. I hope to get back on it this week. Take care.

Bill Gaiche · « **Reply #50 on:** June 11, 2011, 06:12:15 pm »

Planman1954, your going to get there soon. This kind of weather sure makes a fellow seek cooler ground. Have you decided on what kind and size of DH you are going to use? bg

Planman1954 · « **Reply #51 on:** June 11, 2011, 08:53:18 pm »

Hi Bill. I'll probably get the same model as pineywoods. He got his at sears I think.

Planman1954 · « **Reply #52 on:** June 13, 2011, 10:34:24 pm »

Got to work this morning for a couple of hours. I finished the siding on the inside of the kiln and went ahead and put all the rafters on:

Then I cut the old metal roofing panels 5' long and painted one side black:

I cut it to length with a circular saw using a fine tooth blade. It worked great. Use goggles. I bought a couple of fans at Walmart to mount in the top, but took them back this evening after pineywoods said I needed metal blades. The ones I bought had plastic blades. They'll melt with the heat. Anyway, I'll have to find a couple with metal blades tomorrow. I also bought the clear corrugated panels for the top at home depot this weekend. The panels ran about $150.00 with the mounting screws. That's all for now. (UPDATE: I found an 18" fan with metal blades at Lowes for $30.00...so I bought two.)

Planman1954 · « **Reply #53 on:** June 30, 2011, 10:48:24 pm »

Finally had some time this morning to get back on the kiln. I stripped the top with 2x4's for the plastic panels, and stained the outside 3 sides. I plan on putting the top panels on in the morning. I'll take a photo and post it tomorrow. Take care.

Planman1954 · « **Reply #54 on:** July 01, 2011, 08:48:11 am »

Here's some pictures of the top installed this morning:

I won't be able to work on the kiln until after the holidays. Happy 4th everybody!

WDH · « **Reply #55 on:** July 01, 2011, 01:15:04 pm »

I will go ahead and place the order for mine now. I prefer the forest green stain

.

Bill Gaiche · « **Reply #56 on:** July 01, 2011, 11:28:39 pm »

Lookin good on the kiln. You are almost there. Try and keep cool on the 4th. bg

ljmathias · « **Reply #57 on:** July 02, 2011, 09:40:28 pm »

Planman: looks great; in fact, looks too good to be just an old kiln. You sure this isn't turning into a Southern sauna? Like we need more heat and humidity as it is.

Lj

WDH · « **Reply #58 on:** July 02, 2011, 09:52:14 pm »

LJ,

I have an outside sauna. Anywhere outside

.

Bill Gaiche · « **Reply #59 on:** August 28, 2011, 09:43:03 pm »

Planman,just doing a follow up on your kiln. Have you been able to finish it up lately? Havent heard much from you for a while. bg

Planman1954 · « **Reply #60 on:** September 16, 2011, 10:52:07 am »

OK...back to work on the kiln, after a long hot summer. Sorry for the long delay, but had some other things to attend to. The Kiln is now completed, and ready for a test run.

After attaching the top plastic panels and completing the wiring for the fans and dehumidifier plug, I ran some blocking between the front beam and rafters and made a framed box for the two fans to rest:

After the fans were set in place, I began installing the metal panels under the rafters. Remember, the metal pieces are centered between the top and bottom of the rafters, creating about an 8" space at the top and bottom for air to enter and exit. You can see the first few pieces in place behind the fan above. I used dry wall screws to hold them in place. Of course, the black painted side is facing up. Here's a photo showing the metal installed around the fans:

After reaching this point, my buddy Jimmy came by and took a look and suggested that I seal off the area between the fans to create a plenum, or a mini attic inside to direct the air flow. This shows a picture of the boards filled in between the fans with insulation above:

And then a photo with my camera held really high to show the insulation laid on top of the boards:

After these photos were taken, I filled in the end areas.

Planman1954 · « **Reply #61 on:** October 17, 2011, 03:17:21 am »

OK...finally time to do the doors. As I mentioned before, I decided to use multiple sections in the door area since my opening is about 16'-4" wide. I've seen hinges come loose on too many kilns with even smaller openings, so I decided to hinge a 3' section on each of the 2 ends, and then use removable sections in the center. I ended up with 5 sections, including the 2 doors. Anyway, each section (and door) is a simple rectangular 1x4 frame glued together with biscuit joints. It's pretty flimsy at first, but that doesn't matter. Next, I set the frames in place in the channels I made with the 1x4 trim around the whole opening at the top and bottom. The doors were hinged into the ends, and the center 3 frames were set in place. All 5 frames had about 1/2" between them...no perfect fit here....it isn't necessary. Then I began installing the siding over the frames. By setting them in place, this enabled me to keep the siding straight with a string:

Once the siding was installed, I removed the 3 center pieces and installed some 1" styrofoam insulation. Here's the before and after of that:

Next, a screwed my 3/8" x 8" boards to hold the insulation in place (being careful not to let the boards interfere with the fit on the channels:

Here's a photo of the completed kiln with the end doors open and the center three panels set in place:

This photo shows the doors open, and one center panel set aside:

And here is a photo of the rear canvas tarp cut to hang down. When a load of lumber is set inside the kiln, the canvas will be laid on top of the stack. This will direct the air flow back up to the rear top of the rafter plenum system:

Here's a photo of the completed Kiln, ready for use:

Mission accomplished!

Bill Gaiche · « **Reply #62 on:** October 18, 2011, 10:58:20 pm »

Looks good. Bet you are glad that job is done and ready to load her up. Tell us what are you going to dry first? bg

WDH · « **Reply #63 on:** October 19, 2011, 07:54:21 am »

Looks great! It sure is in a nice sunny spot.

metalspinner · « **Reply #64 on:** October 19, 2011, 08:02:19 am »

Thanks for all the detailed descriptions and pics.

I'm considering building a new kiln and seeing yours complete has inspired me to think about getting started.

Planman1954 · « **Reply #65 on:** October 19, 2011, 07:28:13 pm »

Well, my brother, a contractor, stopped by today and saw a large stack of beech that I cut into 1" material about 6 months back. He thought he'd ask his cabinet maker if he would like to buy it. If he's interested, I guess I'll load it into the kiln to get it down to 6% mc. Be nice if that works out.
I had planned on drying some cedar logs first in it though. I need to cut them to 1" stock and then stack them inside. Probably will be a few weeks before I have time to though. Right now I'm tearing down some old fencing here at my place. I'm trying to finish one thing at a time completely before moving on. Take care.

WDH · « **Reply #66 on:** October 19, 2011, 07:38:32 pm »

Quote from: Planman1954 on October 19, 2011, 07:28:13 pm

I'm trying to finish one thing at a time completely before moving on. Take care.

Don't set an unreachable bar for the rest of us

.

ljmathias · « **Reply #67 on:** October 20, 2011, 07:30:01 am »

Wow, beautiful kiln and what a neat idea- doing one thing at a time. I've never been able to do that. Yesterday, working on finishing up plumbing work for the dry wall to go up on the house I'm building, I started with some jackhammer work, laid it down to get a bucket for the chips, saw the door sill plates needed cutting in the closet, picked up a saws-all and did that, then went to get the bucket. Filled and emptied that, then grandson pointed out that we needed to finish framing up his "portal" window, so cut the pieces for that to make an octagon that will be the frame and nailed those in place. Then cleaned out some of the tools and left-overs to make room for the dry wall hangers... never did get back to the jack hammer so that's waiting for today...

Lj

Planman1954 · « **Reply #68 on:** November 06, 2011, 08:58:45 pm »

Hello fellers!
Been working outside this past weekend tearing down some old structures, and took some time today to stack a load of beech inside the kiln. I turned on the fans and the dehumidifier. It was great to see the air finally flowing around a stack of lumber. This particular load of beech has been air dried for about 6 months. The moisture content is about 10% right now. I hope to get it down to less than 6% so that I can sell the wood to a local cabinet maker.
I talked to pineywoods today, and he told me that this design doesn't fit any of the established drying criteria of typical dry kiln operations. He told me to let the fans and dehumidifier run continulously until the moisture content is what I want. During the day, the heat releases the moisture from the wood. During the night, the dehumidifier pulls moisture from the air at a higher rate than during the day. Oh, and btw, I bought my dehumidier at a flea market for 5 dollars. Seems like a good place to look for one, since I bought a second one for 10 dollars! The unit I'm using originally cost about two hundred bucks.
I'll try to take a photo during the week and post it showing the wood inside the kiln. I'll also keep ya'll posted on the time required to do the job. Take care. (UPDATE: The kiln seems to be doing a great job on the beech. I emptied about a half gallon of water the first day from the dehumidifier. When I open the door to check on things, it's almost like sticking my head in a warmer oven...I kid you not!)

Planman1954 · « **Reply #69 on:** November 30, 2011, 11:31:57 am »

Hey everybody:
The cabinet guy came by yesterday and said he would buy the load of beech. I showed him the mc was at 6% or below with a meter. It started at 10% when I loaded it, was 8% at the end of the first week, and now is at or below 6% here a few weeks later. I plan on putting the money towards a planer/molder and try to see if I can sell some crown mold and base. I've been looking at the Grizzly. Anyway, I am very happy with the kiln. It's perfect for a small potatos setup like mine!

WDH · « **Reply #70 on:** November 30, 2011, 08:16:44 pm »

Pineywoods should sell the plans! That is a really nice looking kiln. Post a pic of the beech lumber if you have one.

Bill Gaiche · « **Reply #71 on:** November 30, 2011, 09:11:34 pm »

Planman1954, I like small taters too. Glad you had sucess on your first load. Getting a new toy will be nice. bg

Planman1954 · « **Reply #72 on:** December 01, 2011, 09:25:29 am »

OK WDH. You asked, and now you shall receive:

First off, I remembered that I had taken a photo of the beech before I put it into the kiln. It had air dried for about 6 months:

Here's a photo of the end doors open, with the beech stacked inside:

And here's a closeup of my $5 dehumidier which worked like a champ:

The fellow is bringing his trailer today to pick it up. Next up...a load of red cedar for my brother. I'm cutting it all 3/4" thick (on my saw gauge) and then will surface one face to about 5/8". He's going to use it to line a closet in his home he's about to build. Take care.

pineywoods · « **Reply #73 on:** December 01, 2011, 09:42:32 am »

Re kiln plans. Nope, I'm not the least bit interested in sellin plans. Got too many projects now. HOWEVER, I'm gonna let the cat out of the bag... Planman would be the best source. He draws house plans for a living and has the talent and means to do a first class job. Like I've said before, there's not much unique about this kiln. It's really just a modified chicken coop....but it does work quite well...

Planman1954 · « **Reply #74 on:** December 01, 2011, 09:55:35 am »

Speakin' of plans...why do you need um? Just read the post from start to finish...cut some lumber, and start nailin' it together. That's what I did! But heck, ya'll have an advantage over me here by having some real-world pictures and a how-to guide to follow. It's more than I had. Seriously, that's why I documented the progression so that others could build one. Good luck.

zopi · « **Reply #75 on:** December 01, 2011, 08:04:30 pm »

I think you will find that lumber dried in a cycle such as yours will produce more resilient lumber that is more machinable...

I have a small building out back that is relatively tight...I think I will move it and put a set of panels on and convert it to a small kiln....

customdave · « **Reply #76 on:** December 01, 2011, 09:38:21 pm »

Neat job, well done, very informative , thanks for posting Planman... Play safe..

Dave

pineywoods · « **Reply #77 on:** December 01, 2011, 10:01:04 pm »

Quote from: zopi on December 01, 2011, 08:04:30 pm

I think you will find that lumber dried in a cycle such as yours will produce more resilient lumber that is more machinable...

I have found this to be correct. Hardwoods in particular are less brittle and easier to work when dried in a solar kiln. I am currently drying a batch of sycamore, supposedly one of the most difficult woods to dry.

WDH · « **Reply #78 on:** December 01, 2011, 10:05:18 pm »

Hopefully it won't warp its way out of the kiln before you are ready to unload it.

Planman1954 · « **Reply #79 on:** April 21, 2012, 12:09:38 pm »

I wanted to update a point about the clear plastic panels I used on the top of the kiln. Recently we had a hail storm, and it damaged the panels with about 40 holes. I thought about replacing the panels, and then brainstormed about how to repair them in place. I went to Home depot and bought one more plastic panel along with a bottle of PVC cement. I cut small pieces (about 4"x4") and placed glue on the existing panel around the hole, and then to one side of the new patch and set it in place. It worked perfectly! It took about 2 hours to cover all the holes...problem solved!

I just went out and took a closeup picture showing one of the patches near the corner:

WDH · « **Reply #80 on:** April 21, 2012, 09:21:43 pm »

That must have been some hail storm!

Bill Gaiche · « **Reply #81 on:** April 22, 2012, 01:03:52 am »

Hope mine never sees a hail storm like that. But if it does, now I know what to do. Thanks planman for the tip. bg

Woodchuck53 · « **Reply #82 on:** April 22, 2012, 05:03:24 am »

Planman1954. Thank you for posting this project. As I sat here and read it I thought that would be the answer to a project I need to do.

I have a 16' home built building that is actually 3/4's of the way having me one like that. And I was thinking of tearing down the little shed anyway. A little whittling and I will have one too.

This is why I like this place so much. Stay safe guys.

Spalted Dog · « **Reply #83 on:** April 22, 2012, 08:01:30 am »

Great Kiln and writeup, I am hoping to build one similar someday soon. Please keep us posted on how it is operating. Thank you for posting

mikeb1079 · « **Reply #84 on:** April 28, 2012, 09:02:11 pm »

hey fellas, nice kiln design. i'm almost finished building one very similar, although i've cut vents into the top and bottom similar to the virginia tech design. do you think the pineywoods design would work with the vents and no dehumidifier? or should i plan on closing the vents off and using the air circulation/dehumidifier in the evenings? fwiw i'm in southern wisconsin around 43 degrees latitude if that makes a difference...

Planman1954 · « **Reply #85 on:** May 01, 2012, 10:52:23 am »

Sounds like you're talking hybrid here, so I don't know about effectiveness. The idea of the kiln shown here is the collector panels on top along with fans to physically circulate the heated air around the unit. The dehumidifier helps to quickly remove the moisture from the circulating air. I suppose any dehumidifier in a kiln would help, no matter what the design.

pineywoods · « **Reply #86 on:** May 01, 2012, 11:38:32 am »

mikeb, I can only relay our experience. When we first built these kilns,there were no vents and no de-humidifier. SLOW SLOW and difficult to get wood below 12 -15%. The little d-h unit made a world of difference. Lumber bottoms out at around 6%. They are cheap 1 room units from sears.Vents...If you vent out the hot humid air, it has to be replaced with something, ie wet humid air from outside. This limits how dry you can get the lumber. The virginia design lays the metal collector on top of the stack, thus cooking the top layer of lumber. Fastening the collector metal to the bottom of the rafters allow 50% more collector area, plus the fans can pass air along both sides of the collector. Temps of 160 deg + are easily obtained...The optimum slope on the collector is 90 deg to the sun, but that varies by lat, season, and time of day. A good compromise is match your latitude..The only material I bought was the plastic roof and insulation. Everything else came off the woodmizer..

Planman1954 · « **Reply #87 on:** May 01, 2012, 06:33:37 pm »

Someone asked earlier about how well the kiln works. The answer is fantastic. I've gotten readings with a meter of 12% mc in as little as 4 days! For exterior use on my barn/rec room project, that'll work fine for the exterior boards. The interior boards I'll be leaving in for a considerable time, mostly with the fans and dehumidifier off...just to keep them stable. Running the fans during the early drying cycle gets the temperature high enough to kill bugs and larvae.
Here's the latest load I put in today. I still don't have a tractor...I do everything manually. But for me, that's just fine...all the sweat helps get me in shape! I remember my Daddy always wondered why folks would exercise and not just work. He liked having something to show for the effort expended....

Den Socling · « **Reply #88 on:** May 01, 2012, 09:26:43 pm »

What species can you dry in 4 days?

Planman1954 · « **Reply #89 on:** May 01, 2012, 11:01:28 pm »

Southern Yellow Pine...remember I said that it lowers the moisture content to around 12%...that's running the fans and dehumidifier night and day...good enough for exterior use on my project. Getting down to 6% mc takes about 2 weeks. It gets sooo hot in the kiln...when you open the door, it'll hit you like a low oven.

Den Socling · « **Reply #90 on:** May 01, 2012, 11:26:07 pm »

Everybody has to note that SYP is easy to dry. Hardwood would take much longer and would still be iffy.

pineywoods · « **Reply #91 on:** May 02, 2012, 11:25:18 am »

Quote from: Den Socling on May 01, 2012, 11:26:07 pm

Everybody has to note that SYP is easy to dry. Hardwood would take much longer and would still be iffy.

longer, yes. iffy, no...Ran a bunch of water oak through mine, made tongue and groove flooring. No problems with the wood, took about 6 weeks to dry...Plannman dried a batch of beech, used to make cabinets.

mikeb1079 · « **Reply #92 on:** May 02, 2012, 03:38:49 pm »

thanks for the feedback fellas. i should've been more specific: i'm definitely using the pineywoods idea of a solar collector mounted under the greenhouse plastic. i guess my question was more to the venting and need for de humidifier. sounds like you guys are def recommending a de humidifier but it sounds like i should make my vents closeable so as to control the amount of outside air coming in?

vfauto · « **Reply #93 on:** May 06, 2012, 07:28:17 am »

Kiln looks great, just have a couple of questions.How long did you let your construction lumber dry before building the kiln? What is 3/8" x 6" lap siding and do you mill it?

Thanks Frank

Planman1954 · « **Reply #94 on:** May 06, 2012, 09:47:54 am »

As I remember, the pine I used to build the kiln was air dried for a few months before I used it for the kiln. (There is a photo of it on the post.) The thin 3/8" x 8" boards were cut on my mill and used for the inside wall areas. The outside lap siding tapers from about 1/8" to 5/8" and is 8" wide. I think the exposure (or the part that shows) is about 6 1/2". I cut all the lumber on the kiln. I think there is a photo near the beginning of the post showing all of it cut. Hope this helps.

vfauto · « **Reply #95 on:** May 06, 2012, 10:42:45 am »

I saw your pictures they look great.Thanks for the info.How do you mill lap siding?
Thanks Frank

Quote from: Planman1954 on May 06, 2012, 09:47:54 am

As I remember, the pine I used to build the kiln was air dried for a few months before I used it for the kiln. (There is a photo of it on the post.) The thin 3/8" x 8" boards were cut on my mill and used for the inside wall areas. The outside lap siding tapers from about 1/8" to 5/8" and is 8" wide. I think the exposure (or the part that shows) is about 6 1/2". I cut all the lumber on the kiln. I think there is a photo near the beginning of the post showing all of it cut. Hope this helps.

Planman1954 · « **Reply #96 on:** May 06, 2012, 08:27:41 pm »

I thought you might ask that! First, I saw a cant 8" wide and stand it up on my mill. It doesn't matter how tall it is. Then I take a few little pieces of 3/8" x 3/8" stock (no more than 6" long) and slip them under the edge of the cant in a few places for support on the infeed side of your bandsaw mill. You've now successfully tilted your cant just right! Drop the blade about 5/16" from the previous flat cut and make a cut. Voila! A piece of beveled lap siding. Take the little pieces out for the next cut and, this time, drop your blade about 11/16". You'll get into a routine of 1" increment drops for the 2 cuts. I just keep going till I get to the bottom and finish off with a flat board of 1" or 1 1/2"...where-ever I end up. That's how i've cut a ton of siding... Have fun.

Planman1954 · « **Reply #97 on:** May 16, 2012, 06:34:39 pm »

Vfauto:
I looked back, and I don't think I've shown any pictures of the lap siding I use around here. Here's one:

You can see the tapered profile of the boards from the end view. They nail on easily due to the thickness....5/8" down to about 1/8". Yeah, I know they vary a little, but once they're nailed on, they fit great. Oh, and that's not blood...it's paint. That's the color the recreation/music room/old barn will be soon!

(UPDATE: I decided to start a thread on making and installing 8" beveled lap siding. I guess I'll list it under the General Board category.)

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