kiln construction questions

bkaimwood · February 04, 2016, 06:30:28 PM

Eurathane is awesome, sticks to everything, deals with the worst of environments, and is extremely difficult to get off once cured...not cheap...I'm referring to the kind that holds windshields in cars....my second go to would be 100% pure silicon, no latex. Everything I ever used with latex in it did not tolerate expansion and contraction well....

Denny · February 05, 2016, 07:49:42 AM

So one vote for butyl rubber latex caulk and one vote for a urethane caulk. One thing about my kilns is that the fan shafts are lubed with 20wt oil and over the years the oil feed lines and/or return lines start to leak oil. Six of my kilns are lubed this way and all six kilns have a thin coating of this 20wt oil in a lot of places, mostly above the kiln charge in the 'fan deck' area where the fan shafts are lubed and the lines are run. So I need a caulk that adheres with the least amount of prep work. These fan decks suck to work in, they're dark, hot, dirty from oil and not so easy to access. It would be a chore to de-grease everywhere I want to caulk.

Xlogger sorry for using your thread for my caulking question, I've been wanting to ask you guys your opinion on caulking for a while and I didn't want to start a thread just about caulking so when I seen the title of this thread I figured this would be a good time for me to ask my question.

For those interested, the Google tells me...
"Urethane caulks are exciting because they are similar in many respects to the popular silicone caulks. But, in my opinion, urethanes are better.

Urethane caulks will give you these benefits:

Paintable
High Tear Resistance
Low Shrinkage
Water Resistant

Urethane caulks adhere very well to vinyl siding, cedar wood, aluminum siding or gutters, and brick.
One of the reasons urethane caulks stick so well is that they actually bond to things by crosslinking on a molecular level. If you get some on your skin and don't wash it off quickly, it will be there for a few days until the oils from your skin finally loosen it.

Urethane caulks are paintable. It is true, but you must allow them to cure before you paint them. The curing process can take up to 7 days.

Sunlight can degrade urethane caulks that are not painted. The caulks begin to chalk like old fashioned paints. They still bond well - they just don't end up looking so good."

bkaimwood · February 05, 2016, 08:22:57 AM

Quote from: Denny on February 05, 2016, 07:49:42 AM
So one vote for butyl rubber latex caulk and one vote for a urethane caulk. One thing about my kilns is that the fan shafts are lubed with 20wt oil and over the years the oil feed lines and/or return lines start to leak oil. Six of my kilns are lubed this way and all six kilns have a thin coating of this 20wt oil in a lot of places, mostly above the kiln charge in the 'fan deck' area where the fan shafts are lubed and the lines are run. So I need a caulk that adheres with the least amount of prep work. These fan decks suck to work in, they're dark, hot, dirty from oil and not so easy to access. It would be a chore to de-grease everywhere I want to caulk.

Xlogger sorry for using your thread for my caulking question, I've been wanting to ask you guys your opinion on caulking for a while and I didn't want to start a thread just about caulking so when I seen the title of this thread I figured this would be a good time for me to ask my question.

For those interested, the Google tells me...
"Urethane caulks are exciting because they are similar in many respects to the popular silicone caulks. But, in my opinion, urethanes are better.

Urethane caulks will give you these benefits:

Paintable
High Tear Resistance
Low Shrinkage
Water Resistant

Urethane caulks adhere very well to vinyl siding, cedar wood, aluminum siding or gutters, and brick.
One of the reasons urethane caulks stick so well is that they actually bond to things by crosslinking on a molecular level. If you get some on your skin and don't wash it off quickly, it will be there for a few days until the oils from your skin finally loosen it.

Urethane caulks are paintable. It is true, but you must allow them to cure before you paint them. The curing process can take up to 7 days.

Sunlight can degrade urethane caulks that are not painted. The caulks begin to chalk like old fashioned paints. They still bond well - they just don't end up looking so good."

Good info, Denny...one good point is that urethanes cure at a molecular level, which makes them stick to everything, and make them very hard if not impossible to remove...the only thing I would add is that I believe automotive grade urethane does not break down due to sunlight, as hardware store or other grade products may. My logic is, that to some degree, being it is used to hold a windshield in a car, and does actually provide for additional structural integrity, it would not be permissible to use if sunlight caused any significant degrade. It is, in most cases, somewhat shielded by exterior and interior trim moldings and what not, but definitely gets some degree of sunlight exposure. Ever try removing a windshield from a 30 year old vehicle? A testament to its bonding capabilities and lack of degrade, for sure...just some additional thoughts...

GeneWengert-WoodDoc · February 05, 2016, 10:55:50 PM

Because things always are moving in a kiln with the heat and cooling, any caulk needs to be very flexible when sured.

YellowHammer · February 05, 2016, 11:45:36 PM

I've got both a metal kiln and a wooden kiln and have tried about every kind of caulk I can get at Ace or Lowes/Home Depot. Seems like they all start to fail shortly after being put into service in a kiln environment.
The absolute best caulk I have ever used for metal, and what I use in my shipping container kiln is a product sold by Great Dane Trailer, who build and repair the big semi tractor trailers. It is a gray product called Silaprene, which is a highly viscous, solvent based neoprene caulk. It's the product of choice for repairing trailers and containers which undergo a lot of flexing on the road. It's also an adhesive, and very strong. It's also used to repair overseas shipping containers, which see a marine environment.

The best caulk for a wooden structure or fiberglass is a commercial industry standard, comes from the marine world, and is 3M 5200 polyurethane adhesive sealant. I done lot of work on my saltwater boats and 5200 is amazingly strong, stay flexible, and is the caulk of choice for marine boatbuilders where a failed caulk joint can not be tolerated.

I've tried Lowes brand neoprene caulks and they weren't close.
I've tried butyl rubber caulk, but it shrinks a lot, drawing up, and takes several days to cure.

Tree Dan · February 12, 2016, 07:56:05 PM

Yaa got err wired up and ready for the first load ?

xlogger · February 19, 2016, 07:25:55 AM

All that is left to do is build box outside for controller, hook up thermostat for heat exchanger from OWB and put on door cam locks. Got the shelve built yesterday for the extra 4 fans and they do put out a good amount of air. Does the controller have to have heat below freezing is not running the DH? I'm going to put in a 60 watt bulb in box to use as needed.
Also my first load I'd like to put in is 8/4 maple and walnut slabs. They both been air dried and now in solar kiln for about a month now. At 3/4 deep it says that my MC is in the middle teens. How would you run those?

WDH · February 19, 2016, 07:30:10 AM

The controller is supposed to be above freezing, so the light bulb in the box will work.

I would set the dry bulb at 120 and the wet bulb at 75 and let er rip.

xlogger · February 19, 2016, 08:02:52 AM

But does the controller need heat if unit is not running?

YellowHammer · February 19, 2016, 10:45:47 AM

Quote from: xlogger on February 19, 2016, 08:02:52 AM
But does the controller need heat if unit is not running?

Short answer, "yes" because it's a good preventative, protective measure.
Long answer is that a light bulb or a warm source is very desirable in the kiln control box both at temps below freezing as as well as many months of the the year above freezing. If your unit has an LCD display, and it is it not rated for far below freezing temps, there is a chance it will degrade over time and start to black out. I've had many LCD's in the past do just that, from depth finders to equipment displays. I know the manufacturer specs say they are good to temps below freezing, but it is a slow degrade that will get it over a period of months or years.
For any unsealed electronics, which these are, used in a semi outside environment, (mine are in a metal weatherproof box) any time the dew point is right, water vapor may condense on and inside the unit, causing accelerated corrosion and other problems to the electronics and contacts. When the unit is running, it generally will put out enough heat, especially in the spring and summertime, to keep condensation from forming. If the unit is turned off, especially in the cool damp spring mornings, and it is not kept warmer than the surrounding surfaces, it may get condensation in it.
I have a light bulb in both my kiln control boxes, they run 24/7/365.

Incidentally, if you ever have problems with cast iron tools like planers or saws that are kept in a shed or barn, you've probably battled rust or even seen the wet metal surfaces in the morning. I use light bulbs clipped to the inside of my planer and on my saws to prevent this well into the summer time.

xlogger · February 19, 2016, 06:15:30 PM

I talk to Stan at Nyle today and he said the same thing you just said. I had a few other questions for him also. He also suggested putting heat tape around the controller instead of a light. I looked at the tapes at Lowes today and decided on a light bulb and put a 60 watt bulb in it. I'm getting slower in my older age, what I thought that I would of got done in a few hours took all day and still didn't finish. So back to work on it tomorrow, my heating guy is coming in the morning to hook up thermostat on heat exchanger. I'd like to think I'll be finish tomorrow but we'll see. This project is been more costly than I plan so I need to get it going and get some money back.

YellowHammer · February 19, 2016, 08:05:02 PM

Good ol Stan. He's a great guy, and I'm sure if you mention my name you'll get a belly laugh out of him. I've know him for a long time. I've still got one of his screwdrivers; he forgot and mistakenly left it as a "gift" in one of my kilns when he assembled it. I told him next time leave a beer in it instead.
:D

xlogger · February 20, 2016, 05:36:55 AM

He talks good of you, he was laughing at me yesterday for telling him I was waiting till it got above freezing to go out and work on kiln.

xlogger · February 20, 2016, 06:24:54 AM

Danny, at those DB and WB temp I trying to figure out this. Does that mean that the wood will get a MC of 2.3?

WDH · February 20, 2016, 07:08:21 AM

No. The dry bulb will get to 120 degrees, but the wet bulb never will get to 75 degrees. When you get a 30 to 35 degree difference in the dry bulb and the wet bulb then your wood is dry, and you will get very little water out of the kiln, maybe less than a cup or cup and a half after a full day. Setting the dry bulb at 120 and the wet bulb at 75 just means that the compressor will run 100% of the time, and that is what you want when starting with air dried lumber. I do not believe that the unit can dry wood below 5 or 6% moisture content.

When your wood gets dry, the dry bulb temp will rise as you are not using as much heat to evaporate water as you have already evaporated it. So, you have to watch the dry bulb temp and open your vents to keep it below about 133 degrees or the high temp shut off will trip, and you will have to take the panel off and hit the reset button.

At start up with a fresh load of about 900 BF of air dried wood in the L53, I get 10 gallons of water a day. When the wood is dry, there is almost no water. Keep up with how much water you get each day as that is an indicator of how dry your wood is.

YellowHammer · February 20, 2016, 08:20:10 AM

Tip of the day- as Danny says -measure your water output.
Nothing fancy, take a bucket and put it under the drip tube. First bucket I used had gallon marks on the side. Check it and empty it every day until you get a feel for things, and correlate it to the moisture content of the wood. After awhile, you'll be able to look at it and instantly tell how well the system is working.

xlogger · February 20, 2016, 06:24:51 PM

I remember Danny telling me awhile back, but I was just looking on the chart in the manual and saw that.
Getting real close now finally. Some bolts on the front board came loose connected to the pad and my guy that help me said he had something to fix that and we will do that Monday. I need that board tight because the bottom latch on the door cam lock will pull hard on it.
I didn't get the power vent but I'm thinking about ordering it. After looking in the manual I believe the wires hook up to the control box. Is that they way you had to do it?

Glenn1 · February 20, 2016, 08:28:24 PM

Quote from: xlogger on February 20, 2016, 06:24:51 PM
I remember Danny telling me awhile back, but I was just looking on the chart in the manual and saw that.
Getting real close now finally. Some bolts on the front board came loose connected to the pad and my guy that help me said he had something to fix that and we will do that Monday. I need that board tight because the bottom latch on the door cam lock will pull hard on it.
I didn't get the power vent but I'm thinking about ordering it. After looking in the manual I believe the wires hook up to the control box. Is that they way you had to do it?

I believe that there are just two wires that go into the control box. It was an easy installation. Since I have a day job and travel a few days each week, I couldn't do without the automatic vents. I also ordered the direct link to my computer so I can see exactly what is happening in the kiln. It works wonders when I am stuck in a hotel hundreds of miles away. Just have to call my wife and she can adjust the lights and fans. 8)

pine · February 20, 2016, 08:40:50 PM

Quote from: Glenn1 on February 20, 2016, 08:28:24 PM
........................I also ordered the direct link to my computer so I can see exactly what is happening in the kiln. It works wonders when I am stuck in a hotel hundreds of miles away. ...................................................

First I have heard of the direct link to a computer and monitoring from elsewhere. Anymore information on that subject? I have an L-200 and would find that useful.

Glenn1 · February 20, 2016, 09:08:22 PM

A year ago last January, I took the kiln course at Syracuse University. Two guys from Nyle were sitting next to me for the week. They told me about the direct link and it has worked as advertised. I ordered 200' of thin wire from them and ran it thru conduit into the house. You can set how often you want it to record conditions in the kiln and I have new numbers every minute. It gives the DB, WB, if the heater is on, and if the automatic vents are triggered. I believe that I paid close to $400 for the entire setup.

WDH · February 20, 2016, 11:49:04 PM

Now that is awesome.

xlogger · February 21, 2016, 09:35:43 AM

Glenn does have a good setup. OK Glenn, got the heat exchanger running this morning. Should be cooking wood in a day or two, come on by.

Glenn1 · February 21, 2016, 08:26:11 PM

I'm glad to hear that you'll be up and running in no time. Give me a couple of weeks and I'll be happy to visit. Next weekend, I have to work with a sawyer and go into the mountains to look at logs.

xlogger · February 22, 2016, 06:40:43 PM

I got it finish and loaded late today. Temp was about 56 and I cut on extra fans and heat exchanger from the OWB, it been about two hours now and the temp is about 75. I cut on the controller with all the controls cut off. It said my heater status and humidifier status was on. So I just cut off the controller and will wait till it gets 80°. Question, after it gets to 80 can I just cut on compressor, I have it set at 75 like Danny suggested and will leave my heat exchanger on set at 120°. I check the slabs before I put them in and they where between 10-11%.

Edit: Got Danny on phone and he explained it to me.

kelLOGg · February 22, 2016, 08:39:37 PM

Congrats, Ricky, on getting it up and running!!

I paid Ricky a visit this AM and saw his lumber operation. Very neat, well organized and lots of wide lumber drying. It made my day! ;)

Bob