What is the best way to seal the ends of the collector on the corrugated polycarbonate roofing material? Do you add foam that fits betweenthe corrugations and the header? Second, when following Pineywood's design, where and how are the fans mounted?
Thank you,
Caveman
The box stores where you will probably get your glazing will have strips of 1X2 cut to fit the corrugations. the fans are mounted up near the top blowing downward. You need a baffle to force the air to make a 90 deg turn and flow through the stack. I use a chunk of old canvas tarp hung from the fan supports and hanging down to the top of the lumber stack.
Take a look at "Solar Dry Kiln Construction" thread. I have photos covering the build start to finish.
Thank you both. I will try to get JMoore to take some pictures. We are building the kiln on an old trailer house frame that is about 28' long. We are going to make the kiln 20'x7'. The remainder of the trailer will be used for storage (stickers and stuff). We will support the trailer frame before we load it with wood.
Caveman
Hey Caveman...Take lots of photos! It helps others here get inspired by the work.
JMoore took some photos today. We did not get too much done this morning due to the rain. We did cut and drill some brackets that will be used to mount the cross members that will span the trailer.
Planman, when looking through photos of your kiln build, I could not tell if you insulated the floor. If you did not, is there a reason we should not? We were planning on using visqueen as a vapor barrier with insulation on top of it below the floor.
Caveman
Heat rises. I did not think it super important to insulate the floor joists. Of course, it might increase the inside temperature when the kiln is in operation, but I think not very much. I DID use felt to provide a vapor barrier under the floor boards however. I think there are photos of me doing that.
Remember, though that the kiln has reached temps over 180 d. farenheit here in Louisiana. It will dry pine down to 12% in 5 days, and down to 6-8% in another week.
We may forego the under floor insulation. I think it would be a great place to raise rats and other vermin. Skipping the under floor insulation will simplify the build. We got the axles mounted today, welded a new tongue on the trailer, and cut and mounted some 4"x6" ash beams to use as floor joists. JMoore took pictures on his phone. If he posts them to my gallery, I will show what we have completed.
Caveman
If the fan is blowing the air around, then insulate the floor. The fan cancels the idea that heat rises. The more insulation, the less building heat losses and the more heat energy available for drying.
The first photo shows the abandoned trailer frame that we hauled home. Afterwards, we cut the spring hangers and axles loose. Some of the springs had rusted in two. The frame is pretty solid 6" channel.
(https://forestryforum.com/gallery/albums/userpics/22883/IMG_1252%7E1.jpg)
(https://forestryforum.com/gallery/albums/userpics/22883/IMG_1256%7E0.jpg) The trailer has had the springs and hangers removed. Cradles for the axles were made out of 3"x6" tubing, axles were flipped over, some used tires and wheels were added (center holes of wheels were 1/8" too small for hubs), and some of the rust was brushed off. This trailer will not be used on the road.
(https://forestryforum.com/gallery/albums/userpics/22883/IMG_1258%7E0.jpg)
After the trailer was turned back over, the angle iron brackets for the joists were welded on.
(https://forestryforum.com/gallery/albums/userpics/22883/IMG_1261%7E0.jpg)
The joists are secured to the trailer. Soon we will have to get started on the kiln part of this project.
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My dad helped Jmoore and me some today and yesterday.
If you are concerned about excessive heat loss, there are 2 options.
More /better insulation and double layer glazing.
Or you can just turn up the heat. That's the purpose of the black sheet metal on the bottom of the rafters..Try it, you'll like it 8)
We are planning our build based on your plans and Planman's pictures. It is usually pretty warm here. The daytime highs have been close to 80° and lows in the 60°'s this week--yesterday afternoon, we were swatting mosquitos.
I wonder if the polyethylene film used on green houses would stand up to the heat produced inside the kiln? On the green house at school, the top has two layers of plastic that have a small fan pushing air in between. This air envelope provides some degree of insulation. If it would hold up, we could use the clear corrugated panels for the top, poly film under the rafters up to the fan attic/heat collector and mount black metal to thin strips below it all.
If, after using the kiln, we need to contain more heat, we could go underneath and insulate it. After we build this contraption, I need to find a sunny spot that is not in my front yard that is within reach of a power cord. We may just have to make a sunny spot.
Thanks for the guidance.
Caveman
Greenhouse plastic might work,I have no idea. But be forewarned that greenhouse plastic will start to break down after what ever the manufacturer says to replace it. When we had ours it would only last 4-5 years. May still look good,but it won't let as much sunlight through it.
That is a good point about the reduced transparency of the plastic over time. We will build it first without it and if it does not get hot enough inside we may experiment with it. I guess we could put a small piece of the poly film between the black metal collector and the clear corrugated panels and see if it melts. If it turns to goo we will know not to use it.
Caveman
It is good to appreciate that the amount of energy into the kiln is the same if the collector is right under the glazing or many feet away. It is the solar shadow that determines the input. (I recall one kiln that used a corrugated collector supposedly to increase the energy input. But it is the amount of energy entering the kiln through the glazing that is the key, not the absorber area.) If the inside of the kiln is black, then 100% of the incoming energy will be absorbed and converted to heat.
If the kiln is well insulated, then the major heat loss will be through the vents (so do not over vent) and through the collector's glazing by convection to the outside and radiation. Radiation and convection losses are reduced if the absorber is further away for the collector. Two layers of glazing improve efficiency by almost 50% faster drying.
Two questions---
If you have an insulated floor, you have mice and rats. What do kiln users do about this?
I would like to build my kiln where there is no electricity. Would a couple of the solar powered vent fans that are used on boats (like Nicrovent, or similar items sold on Ebay)) provide adequate venting for a kiln built to dry a 5'x12' stack of lumber? They are rated to move appx 100 cu.ft/hr, and some even run on rechargeable battery power for several hours after sundown...
I've never had any problems with rodents. There are trade offs in life, and this seems to be one of them! I chose no insulation in the floor, and have had no problems. (And I still have a kiln that reaches temperatures over 180 degress.) I DID insulate the walls, however.
You need fans to circulate the air in the kiln through the lumber pile. Vent fans are not needed. The cfm is calculated. For example, with 12' long lumber, 20 layers, 3/4" sticker space (0.75 / 12 feet) and 100 fpm velocity required, then cfm = (0.75 / 12) x 12 x20 x 100 = 1500 cfm. Add maybe 25% - 30% for leaks.
In the VA Tech kiln that I developed, we put metal hardware cloth on one kiln on the bottom, which kept the rodents out, but the insulation was exposed to the ground moisture.On another we put plywood on the bottom of the floor joist and then insulation, then plastic on the warm side only, and then a layer of plywood on the top of the floor.
Thanks for the explanation. And a Happy New Year to all!
(https://forestryforum.com/gallery/albums/userpics/22883/IMG_1264.jpg) JMoore nailed all of the plywood down while I cut it to length. The plywood is 3/4" x 24" that was almost 9' long. We built the joists on 2' centers so each piece had to be cut. We got the plywood out of a dumpster. If its free its for me.
(https://forestryforum.com/gallery/albums/userpics/22883/IMG_1267.jpg)
A short length of 2 1/2" square tubing was welded to the trailer tongue so a receiver hitch could be slid in. A 1" bolt allows it to attach to almost any hitch.
(https://forestryforum.com/gallery/albums/userpics/22883/IMG_1266.jpg) Roofing felt was nailed down to the joists before nailing down the plywood floor. Next, we have to call around and find out where we want to buy the corrugated poly roofing material and cut all of the studs.
Happy New Year,
Caveman
Looking good!
Thank you for the encouraging words. Jmoore was not feeling well today so we did not work on the kiln. Another forestry forum topic turns to food. I am cooking 150 lbs of pork butts tonight and will cook a bunch of chickens tomorrow in preparation for our sometimes annual New Year's Day BBQ. We will use the kiln trailer tomorrow as a two line serving table for the gathering.
Caveman
Does polycarbonate last a long time? See they have double wall polycarbonate for sale in the Farmtek catalog. or FarmTek.com No I don't have any connection to farmtek. Just find some of the things in it interesting, and not available locally.
Quote from: Handy Andy on January 07, 2014, 09:12:27 AM
Does polycarbonate last a long time? See they have double wall polycarbonate for sale in the Farmtek catalog. or FarmTek.com No I don't have any connection to farmtek. Just find some of the things in it interesting, and not available locally.
I build commercial greenhouses for a living, All polycarbonate we use are GTD for 10years.
And for you initial question, we simply use aluminum tape.
Today we were able to get a little more done on the kiln project. We ended up at Lowe's buying polycarbonate sheets, screws and a few other miscellaneous items (I keep hearing folks say that there is no inflation-I disagree). We were able to stand up the small wall, build the tall wall, and install the beam for the 17' opening. Tomorrow we will start building the other three walls. The actual kiln will be about 20' long and the remainder under roof will be used to store stuff for the mill such as stickers. (https://forestryforum.com/gallery/albums/userpics/22883/IMG_1282.jpg)
(https://forestryforum.com/gallery/albums/userpics/22883/IMG_1283.jpg) (https://forestryforum.com/gallery/albums/userpics/22883/IMG_1285.jpg)
Thanks for documenting so well! Really looks nice, great progress.
JMoore and I got a bit more done on the kiln project this weekend and today. We made the three end walls (remember we are using part as storage), made the rafters, installed the rafters and walls and began making the roof purlins.
The real time consuming part of this project has been using substandard lumber. Most of the lumber that we are using for this build was sawn from really poor trees and it has been stacked in our saw mill shed for a year or more taking up valuable space. It is refreshing to find a use for it and get it out of the way. Most of our good dimensional lumber has been used or sold. Also, we used the few pines we had stored in my pond to saw siding out of for the kiln. I sure wish I had a few good pines ready to saw. We have quite a variety of species used in the construction so far--longleaf pine, slash pine, water oak, camphor and some recycled pressure treated pine. We nearly resorted to purchasing some framing lumber today. The goal for today was to get a roof on it--we did not get that far. Hopefully Jmoore will post some pictures from his phone to my gallery to provide a visual update to the progress.
Caveman
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Slow and steady wins the race. It'll be done before you know it. Thanks for the good photos.
Thank you to all who have given advice on how to complete this project. The weather guy needs to be fired-he missed the forecast again today, it rained. I had my middle daughter with the leaf blower forcing water out from under the plywood floor which has roofing felt underneath. I hope that JMoore and I will be able to get the polycarbonate on Thursday after work. Thankfully the days are getting a bit longer. John found plenty of foam board in a Craig's List ad to insulate the whole kiln project twice for about half of retail but when he called on it last night it was gone. We will keep looking since it will still be a little while before we are to that stage.
Caveman
(https://forestryforum.com/gallery/albums/userpics/22883/IMG_1311.jpg) Since I posted photos of our kiln project, we have installed the polycarbonate roofing and metal over the shed portion of the trailer. Also, we began installing the siding (3/4" random width longleaf pine).
(https://forestryforum.com/gallery/albums/userpics/22883/IMG_1318.jpg) It was time for another cup of coffee after siding the sunny side.
(https://forestryforum.com/gallery/albums/userpics/22883/IMG_1320.jpg) A little sticker stain won't hurt anything on this project. This is from the tongue end of the kiln.
(https://forestryforum.com/gallery/albums/userpics/22883/IMG_1321.jpg) We held the walls in 3/4" from the floor to allow room for the furring strips. We decided to go a different route on the front which allowed us to saw some really hard ash and some nails.
(https://forestryforum.com/gallery/albums/userpics/22883/IMG_1323.jpg) The pull string on my little Echo broke when trying to start it. I trimmed what I could with my Milwaukee circular saw but it was unable to get to everything.
(https://forestryforum.com/gallery/albums/userpics/22883/IMG_1324.jpg) Safety 3rd!
This past week was full of 16-18 hour days at the county fair. The state fair begins Wednesday and will be going on for two weeks so I doubt I will be able to work on the kiln project much for a while. It will give it a few days to dry out as this has been about the rainiest January that I can remember. JMoore and my dad did find some Styrofoam that we can use for insulation when we get to that stage. We also have to locate and harvest a few more pine trees to finish this project. Thank you for reading and we are still open to advice from those of you who have already been down this path.
Caveman
It was raining here tonight and I went into the kiln building to check for leaks. Unfortunately, I found three. There was water dripping off of the purlins. I suppose that we did not tighten a few screws tight enough to seal the rubber washers. With the oak that we used for some of the purlins and rafters, we should probably find and fix the leaks before proceeding on this project or it will rot before our eyes. Maybe this weekend we will get an opportunity to locate and fell enough trees to finish this project.
Caveman
Looks great. Gonna be drying lumber before you know it. Have you found a dehumidifier yet?
Thank you for the encouraging words. We have had the dehumidifiers for months. A young lady who works with me does a lot of garage sale shopping with her mother in law. She picked up two of them for $15, one was like brand new but both work. We gave her a $20 for her trouble.
The boards we have nailed on now have gaps of about 3/16" to 1/4". We will need to saw the rest of the boards we need to finish the kiln and a bunch of battens. We should be able to work on it some this weekend.
Almost every day since January 25, has been spent at a fair or getting ready for a fair. Our state fair will end next Monday. I hope I will be through with it on Saturday morning. I should probably try to fix the leaks this afternoon since I am home and it is day time (rare lately) but I am tired.
Caveman
I can relate on the tired part...had a stomach bug lately...BAD! Good job on the dehumidifier finds. That's what I posted on my build thread. People sell them once they're done with them, and you CAN find them cheap.
Planman, I hope you are over your maladies and up to snuff. JMoore and I got an opportunity to tighten every screw on the roof to try to slow down the water getting in. We then ran a hose on the roof for a while and declared it fixed. Saturday afternoon while working on another part of the kiln it began to rain and we had one leak. After careful inspection by JMoore, he discovered a hole we drilled in the polycarbonate but did not fill with a screw-it has one in it now.
Monday, Presidents' Day, JMoore and I cut down a decent longleaf and a 26" slash pine. We came home and began turning the logs into siding for the inside of the kiln (9/16" x 10" or so), 1"x3" battens for the outside and also for framing the panel and doors. We still have a few good logs to saw, at least one will be used for siding for the panel.
(https://forestryforum.com/gallery/albums/userpics/22883/IMG_1331.jpg) This is a picture of my folks inspecting our work after they got home from church. We have nailed on the battens, built two doors and hung the doors, and sided the kiln above the opening.
(https://forestryforum.com/gallery/albums/userpics/22883/IMG_1332.jpg) This is the panel. It is framed out of the same boards that we used for battens, a plastic vapor barrier was installed and the plywood was nailed on.
(https://forestryforum.com/gallery/albums/userpics/22883/IMG_1334.jpg) JMoore and I carried the panel out of the shop and lifted it into position to see if it would fit between the doors. It is already heavy and the board siding and insulation still has to go on. When we begin using the kiln, we will install and remove the panel with the tractor's forks.
(https://forestryforum.com/gallery/albums/userpics/22883/IMG_1336.jpg) This is what it currently looks like with the panel sitting in place and the doors shut. I hope that when we carefully move this behemoth that it does not cause any leaks in the polycarbonate roof. Thanks for reading.
Caveman
Thanks. I'm feeling better! I think you'll find the access doors on the ends will work well for checking your lumber mc as it is drying. I used 3 sections in the center so that I can lift them out myself. Using the tractor forks will be handy also though. Looks like you're ready for some upper black metal and then some insulation!
This afternoon I had aspirations of sawing some more logs into the boards we need to finish the kiln but we had a bit of a frog strangler. After the rain let up I went out to the kiln project to check for leaks. We had three a few weeks ago, last week we had one (it is amazing how much water one drilled hole in a roof without a screw and washer will let in), today there were none.
There was about half an hour of daylight left so I unloaded the three logs on my trailer, filled the gas tank and the water bottle on the mill. Tomorrow we will try to saw out the rest of what we need.
Caveman
(https://forestryforum.com/gallery/albums/userpics/22883/IMG_1341.jpg)
(https://forestryforum.com/board/proxy.php?request=http%3A%2F%2Fwww.forestryforum.co%2520allery%2Falbums%2Fuserpics%2F22883%2FIMG_1341.jpg&hash=78c8caa42a3aaac0dad644733e04188842544b2b) This is the removable panel on the front of the kiln. We only installed one layer of foam insulation in this panel and the doors.
(https://forestryforum.com/gallery/albums/userpics/22883/IMG_1338.jpg) On all of the walls, we--mostly John--installed two pieces of foam between the studs. I cut them close to the right size and he used a hammer and a block of wood to encourage them to conform to the space available.
(https://forestryforum.com/gallery/albums/userpics/22883/IMG_1342.jpg) We made quite a mess. Hopefully we will finish the wall insulation tomorrow afternoon and enlist the kids to help us clean up. We have a lot of foam left so at some point we will insulate the area between the floor joists.
I also realized that I have accumulated enough scrap metal to justify hauling it off.
Caveman
As Andy stated in his post about his kiln, JMoore and I took a few more bites out of the elephant this afternoon. We were able to get the boards and battens on the doors and the removable panel. We still need to panel the inside, insulate under the floor, build the plenums for the fans, wire it, paint and install the metal collectors. The pictures are of the side we will load the kiln from.
(https://forestryforum.com/gallery/albums/userpics/22883/IMG_1350.jpg)
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Caveman,
That elephant looks mighty tasty! The B&B siding looks like it belongs there. When complete, are you going to move it around, or set it up stationary? Good looking job, and if you can, show pictures of the fan plenum and baffle. Stay safe, Andy
Andy, we plan to move it to a sunny area, which we may have to create at my place due to all of the live oaks, and orient it to collect the most energy from the sun that it can. I want to be able to move it but do not intend to move it much once we find a good place for it. We have not started on the plenum. I have some regular garage sale shoppers looking for some metal bladed fans. We will build the plenum to fit the fans. I suppose the next step will be to panel the inside with the 5/8" boards we cut for that purpose a few weeks ago. Also, I need to locate some long bolts to mount a 4"x4" to the removable panel to give me somewhere to grab it with the tractor forks.
Caveman
(https://forestryforum.com/gallery/albums/userpics/22883/IMG_1455.jpg)
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(https://forestryforum.com/gallery/albums/userpics/22883/IMG_1462.jpg) We have not posted anything on the kiln build in nearly three months. JMoore has been busy with his son's tee ball team. I have been really busy with work (ag teaching) and dealing with damaged knee cartilage. Today, we (mostly John) made a little progress.
John suggested putting the chicken house insulation on top of the floor instead of beneath and between the joists. We did this and decked it with another layer of 5/8" plywood we salvaged months ago. The plenum was framed with 1" x 3" pine and sheeted with some more salvaged plywood. A few months ago, I painted some used metal roofing black. This morning we installed that also.
We located some fans. We need to replace the power cords on them and wire the kiln. The fans each have four 24" blades, and 1/2 hp, 1725 rpm motors. They may be overkill but the price was right.
There is a large panel between the two doors. It is heavier than two of us can routinely lift without making some of our internal parts external. Last week, I cobbled up a skid steer quick connect mount that we will through bolt to the panel. If I can driver a tractor well enough we should be able to remove and install the panel using the tractor's hydraulics. We will need to ensure the ground and the kiln are on the same grade for this to work. If any of you see anything that we should do differently don't hesitate to say so.
Caveman
Wow, I got a warning that it has been over 120 days since I posted anything on the kiln. Today, John and I finally got around to moving the beast. In order to make room for it, we had to take down nine live oaks, a few water oaks and a pine tree. We only had to replace one section of my neighbor's chain link top rail (the darn things were all leaning the wrong way). Also, we had to cut several low hanging limbs between my shop and the kiln spot with a pole saw.
John aired up the tires in preparation for our 400' journey. They were only flat on the bottom.
(https://forestryforum.com/gallery/albums/userpics/22883/IMG_0558~0.JPG)
We hooked the kiln's hitch to the draw bar and John coached me in the backing process (I could not see around the kiln) in order to avoid smashing sheds, trucks, and other obstacles.
After positioning the kiln in the sunny spot we created with the collector facing south, we began the leveling process using old air plane screw jacks, a floor jack and the tractor's forks. We had some fine tuning to do on the doors to ensure they opened and closed smoothly. Finally, we mounted the skid steer quick connect frame that I melted together a few months back. (https://forestryforum.com/gallery/albums/userpics/22883/IMG_0559.JPG)
(https://forestryforum.com/gallery/albums/userpics/22883/IMG_0561.JPG)
Sometime before too long, we need to run about 380' of wire to power the fans, dehumidifiers, lights and a few outlets and lights in the mill shed.
There are no vents in this kiln. When it is empty, would we be wise to leave a door ajar? My inclination is to keep it closed up.
Thanks for looking,
Caveman
Quote from: caveman on November 24, 2014, 07:10:27 PM
There are no vents in this kiln. When it is empty, would we be wise to leave a door ajar? My inclination is to keep it closed up.
With an empty solar kiln, the temperatures will skyrocket, especially since you are in Florida. I live in Alabama and when I had an empty solar kiln, I ended up melting the plastic roof panels from the excess heat. An open door may swing uncontrollably in the wind and may damage hinge hardware. I'd advise putting in vents, (I use 4 simple rectangular foundation sliding vents, placed high and low) but its hard for me to give advice to a guy who's built a work of art like yours. 8)
YH
Thanks, YellowHammer. It gets hot and does not take long. Melting the panels would be an enthusiasm smasher-the panels were the costliest part of this project to date. I was inside some today while John was outside and we were checking tolerances on the doors and panel. In just a few minutes I felt like a poor puppy left to guard the family sedan in a Walmart parking lot during the summertime. We should be able to come up with some sort of vent. The amount of experience and talented folks who frequent this forum never ceases to impress me. It is nice not having to reinvent the wheel.
Kyle
If you left the door ajar, I'd make sure a child couldn't get in there and close the door.
Dakota
A solar kiln without lumber can indeed exceed 200 F.
So when the moisture is evaporated from the lumber, and into the air, how will this moisture in the air be removed from the kiln?
We have a couple of dehumidifiers that we will use to remove the moisture. There is still work to be done before we can start attempting to kiln dry lumber successfully. The biggest obstacle is running electricity to the kiln from the shop ($$$). Also, we need to mix up some stain (boiled linseed oil, diesel and roofing tar) for the outside and make the bottom look more presentable from the neighbor's perspective-she is a great neighbor and I hope to keep her happy.
As of now, we intend to power two kiln fans, two room dehumidifiers, a light or two, and maybe a few outlets (nice to be able to plug in power tools). Is there any other electrical appliance that we are missing?
Thank you,
Kyle
WoodDoc, the dehumidifiers will drain outside through tubes through the floor. Thank you for your expertise and helping all of us aspiring to produce quality lumber.
After moving the kiln yesterday, we were a little apprehensive that the roof may leak due to the flexing during the move. It rained about 3" in two hours this morning and thankfully the inside of the kiln is bone dry, everything else is flooded. Blind hogs...
It is obvious from the pictures that you have a well designed kiln. "No leaks" is indeed awesome. Maybe you should use pine tar on the bottom and add a rudder so you can use the kiln as an ark, if it rains really heavy again.
Venting, instead of DH, can be more efficient, especially with wood that dries easily, like pine.
For your reference, 1000 bf of lumber requires removal of about 28 to 30 pints of water to lower the moisture by 1% MC. So, with the amount of lumber in the kiln and the rated capacity of the DH units, you can calculate the maximum drying rate. This would apply to wet lumber. The units will not dry at their rated capacity when the wood is under 30% MC...we are waiting for the moisture to move from the interior of the wood to the surface, which depends on temperature and humidity and not the ability of the DH unit.
The clear cover will actually lose a lot of heat when dark. So to prolong the usefulness of the DH units at night, cover the collector with an insulating blanket and the heat will stay in the kiln. Of course, with 24 hour drying that will result, you will not relieve the stresses (also called casehardening). This relief is accomplished in a kiln without a DH because at night the humidity in the kiln reaches 100% RH as the kiln cools. Plus in a vent solar kiln, the fans are turned off at night.r
Also, be aware that the household DH units usually will not work above 113 F...they may have an automatic shut off. Above 113 F, the lubrication fails, so the compressors will wear, plus the compression cycle may fail too and blow a gasket. So, you would not use them when the sun is shinning, so you need vents to exhaust moisture in the daytime. Technically, the vents are not opened very wide...just enough to keep the RH from getting too high. We want to avoid exhausting too much heat. Most kiln operators adjust the vent opening once a week.
It has been quite some time since we updated this kiln build. It still has not dried any wood but we ran wire to it last week to power the fans, light and dehumidifiers. We still need to finish the wiring. Jmoore and I mixed up a variation of the Uncle Larry's stain concoction and sprayed and brushed it on using a TSC pump up sprayer and a brush. The pine really soaked up the mix. The cypress we recently sawed will be the first wood to be dried in the kiln. It will air dry for a month or so and then we will finish it off in the kiln.
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Today, Jmoore and I finally got electricity to the kiln. We ran a separate circuit for the dehumidifiers. The fans are on the same circuit as the mill shed. We wired the timers, lights and an outlet or two. He and I work for the local school board and have had the past two weeks off (except for emergencies like busted water pipes and greenhouse irrigation woes-life of an ag teacher). We have run several hundred feet of electrical wire, PVC pipe, mixed and applied stain, wired the mill shed and kiln and found time to mill some really nice bald cypress. The hot air was really moving when we turned on the fans today. I am anxious to see how this contraption works. I guess the next purchases will need to be moisture meters and thermometers for the kiln.
Update: We finally stacked two small loads in the kiln yesterday. One stack of "not very good" cedar slabs and a stack of monkey puzzle slabs were put into the kiln yesterday. This was the first time we removed the large panel that we made the skid steer attachment for. It did not do too bad but it is much easier to remove and install with two people. Basically, we needed room to air dry some nice cedar we sawed yesterday and want to get an idea of how long it will take to dry 2" slabs to below 15%MC.
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I think once we get the ground on the same plane as the kiln and remove the irregularities installing the panel will not take but a few minutes. We have a door on each end that the panel fits between.
Caveman
Glad it's working. It won't be too long.
Yes...please keep us updated! You are the reason I took the time to document the build process. It makes me happy that someone took the initiative to go for it! Take pictures and post your drying times and progress. Thanks.
A few minutes ago I went out to the kiln to check on the 3/4"x3 1/2" 14' boards we stuck in there 12 days ago. We still have not installed vents or turned on the DH. The first week we just propped the doors open with stickers (the kiln stayed quite a bit warmer than the outside even after dark). The past six days we left one door propped open 3/4". The wood seems dry enough to use to mount over shingles and attach metal to. We still have not purchased a moisture meter.
The Monkey Puzzle and cedar slabs that were in the kiln were considerably drier/lighter after a little time in there with the fans running during the daytime and the doors propped open slightly. They are now flat stacked and in hiding.
After listening to Dr. Gene, WDH, and Yellow Hammer this weekend discuss drying wood at The Project, I think this kiln has a chance to produce quality lumber.
The cypress that was intended to be the first load in the kiln has been sticker stacked and drying in the wood owner's shed since early January. He has decided to use it on the outside portion of his house so it will not be placed in the kiln. We still have a good whack of his cypress logs that we will saw eventually. After hearing Jake mention bad behavior by partially dry cypress logs I am beginning to get a little anxious about them.
Caveman