Hot Box

[caveman]

After installing the work lights this morning, I turned them on and one of the `3amp fans.  It took 3-4 hours to heat up to 152°F while empty.   I did not seal up the foam joints.  Mainly, I just wanted to see if the lights would live.  The work lights use the same bulbs as the light fixtures we were using.  The next step is to seal it up a little better, load it with wood with bugs (I laid a cypress board on the ground last week and it has termites now and the carpenter bees are still in a few of our boards) and see what happens.

 Thanks to all who offered guidance.  Hopefully this thing will work as intended.
Kyle

 

[YellowHammer]

Excellent. 

You'll have crispy critters before you know it.  

[doc henderson]

might make good snacks for the pig roast!!!

[nativewolf]

might make good snacks for the pig roast!!!

Waste not want not :D

[caveman]

Update on the box.  We finally loaded it up with some live oak slabs that had been in the solar kiln until Friday morning.  With two 500 watt halogen lights and a small 12 v fan it took until yesterday morning to reach 135° F.  By 6 p.m. it was 145° and holding at 146° this morning.  I will let it run the rest of today and leave it closed up until tomorrow.  The last couple of days have been cloudy/rainy and very humid.  That may have had an affect on how long it took to get to temperature.

The next thing to do before using it again will be to add another light or two to bring it up to temperature quicker (like Yellowhammer does).

One of these days we may get around to building proper barn doors for the kiln and then I expect we will use it more.  The panel, that I thought would be so simple to remove and install, has been a major pain in the neck.  The hot box door hinges were simple to build and with bigger material or more of them, they should work well for the kiln.


 


This worked really well in my mind but in operation there were too many variables.  The ground and the kiln need to be in the same plane, turning the front tires will move the panel several inches even when not moving forward or back, the sandy ground is easily disturbed by turning tires resulting in holes, our header sagged a bit which makes installation even more challenging and from the tractor seat it is difficult to get it aligned perfectly without a spotter on the ground.  I show this to help someone else choose a simpler path.

[YellowHammer]

Glad it worked, but I agree, throw a few more lights in there.  Make the circuit breakers groan an little.   :D

Since you can hold the temps at 1,000 watts, you can boost the speed with a couple or more lights to get up to temp quicker, then unplug all but two and maintain the temps.

[Crusarius]

I would think instead of making a full QD plate on the side if you made only a top to hang it may be easier. then it will be more likely to rotate and set into the mount easier.

I often wonder why some of the attachment plates are such a tight fit left to right. That sure makes it a pain to get lined up perfect to lock into the equipment.

[caveman]

Getting the tractor attached to the plate is relatively easy.  Getting the wooden panel centered perfectly between the two doors is more challenging.

[caveman]

We added another light to the hot box.  It does help bring the heat up quite a bit quicker than two lights.  Two lights will maintain the temp around 150°.  I would like to seal it up a little tighter as it does have a few leaks.

I opened it up tonight to look at a small stack of maple that I put in there yesterday morning.

 

 This thermometer pic was taken the other day.  Tonight it was 152° after turning of one of the lights several hours earlier.

[Nebraska]

As I finished looking this thread and decided to go feed the furnace I thought of these as an alternative  heat source for a kiln instead of halogen lights.
Its a 450 watt adjustable Trojan Hot Scott heater. Used in livestock waters to keep them thawed in winter. This one is  one that w as retired, when the old  hog fountain waterer started leaking. New drinker has a different heat system.  They are adjustable,  hold up to tough  damp conditions. Not very expensive. Just a quick thought as it was on the shelf in the basement.

 

 

[Crusarius]

Those heat coils are intended to be underwater. I wonder how they would hold up in the air?

[doc henderson]

@Nebraska it looks like it will work.  I think cause you mentioned the hog fountain and with the corrosion it looks like it was under water.  I blew up the pic to read the label, and it looks like it is designed as a space heater.  It is nice that is has a thermostat.  I think the brand name implies it is supposed to be covered as well.. :D :D :D :D ;) .@Crusarius

[Nebraska]

Well the underside of a 20+ Year-old hog fountain is a very wet nasty place.. a hot box or kiln would be a walk in the park for this little dude. I usually only got two seasons out of them . It sat on the cement pad  about 3 inches below the stainless water pan. They always go bad when it's zero or worse makes for many magic words when changing them .

[Crusarius]

I thought those were intended to be in the water?

[Nebraska]

No with pictures of the old hog waterer unit  you'd understand, but at work now.  It actually set inside the unit under the water pan, on a  a couple bricks and heated the space underneath keeping the water above thawed as well as the valves and supply line  that comes up from the bottom through a  12 inch cement culvert, set below frost line. @Crusarius , @doc henderson . 
 One could also use an old electric range as a heart source take off/prop open   the oven door  lots of variable controls, but lots of watts,  yes it would eat kiln capacity and yes it's ....Redneck.. you betcha... but easy and cheap to a fault.  Easy bake oven style, cook your chicken and grits in the kiln.   8) 8) ;D

[caveman]

Nebraska, we don't find too many surplus stock tank heaters here.

I do have a question for those who heat sterilize slabs with bark still attached.  Do any of you see fire ants move into the kiln or wood after heat treating?

  The last two small loads of bark on, live edged maple we have run in the hot box were held at or above 150°F for over 36 hours.  When the heat cycle ended and the slabs were left in the box for a few days, there were fire ants which seemed to be feeding on something between the wood and bark and some frass was present which was not there at the end of the heat cycle.  We suspect the ants are showing up to eat dead bugs.  After a few days the ants leave but we can't really tolerate them.  I am relatively confident that the temperature shown is accurate. 

We will probably spread Talstar around and under the hot box before we run another load.
Thank you for your suggestions.

[GeneWengert-WoodDoc]

The highest sugar content area is near and between the bark and wood.  Heat does not destroy the sugars.

[caveman]

Thanks, that is what I was thinking too, but I wanted to read it from the expert (s).

[YellowHammer]

I have had fire ants get in my kiln dried pine that was shot full of dehydrated pine borers and eat them.

I also routinely have to put spetracide fire ant killer around the bottom edges of my kiln where I must have some slight leaks because the fire ants really seem to like those edges.

[Kindlinmaker]

Does anyone else think this post has been extremely informative.  The forum has a wealth of detailed info on kilns and drying which I refer to regularly but this last step, while it gets mentioned regularly, does not seem to get as much detailed info and ideas. I have found this one to be very beneficial on detailed practical application of building a hot box. Just wanted to thank everyone that participated. 

[farmfromkansas]

Was at the local Good Will store a while back, and they had a couple of hot plates.  Would those work for a heat source?

[GeneWengert-WoodDoc]

YellowHammer...Fire ants like dry, dark places especially when raining.  So, your kiln with a nice roof and maybe good drainage, provides a good nesting spot.  They also like to eat plants or animals...they are omnivores.  So, maybe the area around the kiln was turned up when building and so it attracts earthworms.

[Nebraska]

 @farmfromkansas I don't see why not. I bet they aren't expensive, and you won't be out much for trying.  My little heater (hot scot) from the old waterer is 18.00$ new at the local hardware store, I was curious after I posted about it before so I went and checked. On line they are higher. I also decided I need a clone to do the  projects that appear in my head while I read stuff in threads like this.

[mredden]

I have had fire ants get in my kiln dried pine that was shot full of dehydrated pine borers and eat them.

I also routinely have to put spetracide fire ant killer around the bottom edges of my kiln where I must have some slight leaks because the fire ants really seem to like those edges.

Borax mixed with sugar is much cheaper

[dean herring]

Got any pictures of finished kiln?