How to build your own Wooden Kiln at
HomePresented by seedman.com and Joe Windham
For those of you that would like to assemble
your own wooden kiln at home, we have put together the following instruction guide for you to use.
The first thing you will need to do is decide what type of
wood you will use. We recommend using ½ inch cabinet
plyboard such as oak, or walnut, but others such as birch,
cherry, etc. can be used. We are using fir in the pictures
Once you have decided on the type of wood, it is time
to cut it into the correct size pieces. ( Note that many
lumber companies such as Lowes will cut your board for you at
a nominal fee, very handy if you do not own a tablesaw or
other means of making precise cuts ).
You will need the following size pieces of plyboard for
constructing a kiln with inside dimensions of 17x22
1 Ea. Top piece measuring 19 inches x 23 1/8
2 Ea. Side pieces measuring 18 inches x 22 inches.
2 Ea. End pieces measuring 18 inches x 19 inches.
1 Ea. Bottom piece measuring 18 inches x 22
Note, be sure to use wood glue on wood surfaces that
join together, this is a must!
Apply a thin bead to each surface as shown. After joints have
been attached, some glue will usually be squeezed out, wipe
this off with a damp cloth before it dries, otherwise, it may
affect the outside finish of the kiln if you decide to use a
varnish or stain.
Plywood corners can be secured using a
braid gun as shown, or with wood screw or finishing nails.
After attaching the two end pieces and
the two sides together, add the bottom piece.
Now add the piano hinge to the top piece. Turn the top lid
piece upside down and attach hinge to one side.
Now lay the top piece on top of the kiln
and attach the piano hinge to the back of the box as shown. ( you can pick it up at your local hardware store )
Notice how the hinge fits under the top
lid piece and attaches to the back outside of the kiln.
Now that the lid is hinged to the kiln,
attach the short chain that prevents the lid from opening back too far. ( you can pick it up at your local hardware
it's time to measure and cut out the 1¾ inch hole for
the electrical plug. ( This type electrical plug is available
at any Electrical Supply store, we like the flush mount type
for convenience ). Measure a mark 4 inches down from the top
and 4½ inches over from the front.
a 1¾ inch hole using a hole saw bit available at any
hardware store. A cleanly drilled hole is important.
that the hole has been drilled, it is time to mount the
Electrical Control Assembly to the inside of the box.
The Electrical Control Assembly is the heart of the
kiln, it contains a 120 volt heating pad, an adjustable
thermostat ( a hot water heater thermostat available at most
hardware stores ), a hygrometer/thermometer gauge and the 120
volt male electrical plug assembly.
We’ve mounted all of this into a 4 inch square
eletrical wall box found at any hardware store, but you can
use any configuration you like.
that on the backside of the Electrical Control Assembly, you
see the 120 volt male electrical connector. The end of a
standard electrical cord will easily plug into this. This
connector is aligned directly in front of the 1¾" hole
you have drilled into the kiln.
the Electrical Control Assembly to the inside of the kiln
with wood screws through the pre-drilled aluminum angle
brackets attached to the Electrical Control Assembly.
is a photo of the Electrical Control Assembly after it has
been installed. Notice the thermostat adjustment screw
is a photo of the outside of the kiln showing the 120 volt
attach the handles to each end of the kiln. ( you can pick
these up at your local hardware store )
attach 1 inch x 1 inch aluminum angle to the top of the lid.
You do not have to cut angles to 45 degrees as shown, a
square cut will work just fine. You will need to put angle on
the front and both sides of the lid, but not the back as the
piano hinge will provide enough strength there.
You will also need to add the aluminum angle to each of
the outside corners ( see finished photo below ).
The angle adds strength to the box and helps prevent
warping due to the high heat and moisture inside the
recommend making a couple of inexpensive legs out of 2 inch x
2 inch lumber and attaching to the bottom of the kiln to keep
any heat from the kiln from making contact with finished
attach the thumb clasp assembly to the front of the box. (
Available at your local hardware store ) You will notice that
we made a small aluminum filler plate to make the clasp flush
out with the front of the aluminum angle. This is for looks,
the clasp will work fine without doing this.
a ¾ inch hole and install lock assembly. ( you can pick
this up at your local hardware store, we recommend it for
those of you who have small children around )
box is now ready!
Insulation is an option, and one that we strongly
recommend. The kiln will work without insulation, but it is
much more efficient with insulation, plus it protects the
wood from excessive moisture which will cause early rotting
We use 1" commercial air duct insulation ( same type
material large air ducts in homes and commercial buildings
are made from ), as it is not affected by moisture and heat.
All corners are sealed with silver duct tape.
This insulation and tape can be purchased from
commercial heating and cooling supply companies, but can be
hard to locate in some areas.
is a photo of a finished kiln that we have added a small
sliding air vent to the lid. This really is not necessary,
but you may want to do it for looks and convenience.
Excess moisture ( over 75 percent ) can be removed
simply by leaving the lid cracked open slightly. Usually, the
only time you have excess moisture is when you initially
begin curing the tobacco.
This leads up to the question of a humidifier for
maintaining the 70-75% humidity required. Do you have to have
No, you can actually control the moisture by placing a damp
towel or sponge at the bottom of the kiln and adding
distilled water as needed. But this requires daily attention,
and it is rather awkward.
You may want to buy one of the Oshkosh Humidors that hold 10
ounces of distilled water and has an adjustable top to
regulate moisture. Once you've used one, you will never want
to try anything else.
will need to make some type of tray for your kiln. The
purpose of the tray is to keep the tobacco from touching the
heating pad on the bottom and to allow an air space for heat
and air circulation.
is a photo of the tray setting in the bottom of the kiln,
notice that the heating pad does not make contact with the
wood. The center piece is notched to prevent contact.
Components for Building your own Wooden Kiln at
#M20 Electric heating pad
A commercial grade heating pad identical to the one showed
photos above. It has 2 18” long leads. Must be hooked
to a thermostat that you supply. ( a standard hot water
heater thermostat will work fine, and can be found at
almost any hardware store ). 120 volt, 100 watt. Measures
6" x 10".
Note, this item is no longer available. The price just got way out of hand. A few years ago, Birk Manufacturing offered this for 24.95 each, then it went to 48.95, then to 64.95 and our last quote was for 106.95 per pad. There are much cheaper alternatives out there.
One of our customers told us he used a Auto Oil Pan Heating Pad from Jegs Automotive Supply
and it worked just fine, and only cost about $55.00. ( Note: We had another customer tell us he purchased this pad and it did not work for him, so do so at your own risk, we are only trying to pass on helpful info here )
We are on the search for economical heating pads, if you find a source, please E-mail us and let us know and we will pass the info on to other customers.
G98 Digital Hygrometer/Thermometer
Digital Hygrometer/Thermometer is the most precise
instruments for monitoring temperature and humidity on
the market today. We think this is the best device for
kilns, and can be removed and used in humidors as well.
This neat and modern Digital Thermo-Hygrometer provides
precise readings on a large crystal display. Measures
about 2 inches by 3 inches, has a self adhesive strip or
can simply be placed in the bottom of the kiln. Comes
with extended life battery.
M24 Oshkosh Humidifier
This one of a
kind humidifier not only allows you to use distilled
water ( a large 10 ounce capacity not found in any of
the other humidifiers we tested ), it also has an
adjustable top that allows you to precisely control the
humidity in your kiln. This is extremely important as
slight adjustments to humidity may be required during
different stages of the curing process.
The humidifier sits in the bottom of the kiln, below
the stainless steel mesh tray, about center.
We include a free 4 ounce bottle of Propylene Glycol with
the kiln. This humectant/preservative is the same
additive used to make the special care solutions used
in most cigar humidors. Simply add a half ounce of this
to the distilled water ( about 9 ounces ) in the
humidifier to help prevent mold and encourage even
humidification. Additional bottles of glycolene can be
purchased from us for $3.95 per bottle, but one bottle
will last for several curing processes.
F21 Large Cotton Gauze Bags with Drawstring
These large 13 x 17 inch virtually
weightless, reusable cotton gauze bags are the perfect
bag for use in our curing kilns. Very handy when
cheesecloth and burlap are not available. Natural
#G99 Propylene Glycol Propylene glycol USP ( humectant/preservative )
4 ounce replacement bottles of Glycolene
Tobacco Curing/Drying Thermometer
The tobacco and cure-o-meter thermometer is a must have tool for anyone fire curing/drying their own tobacco and just a handy thermometer to have.
Temperature range -20 to 200 degree F/-10 to 95 degree C in 2 degree F/1 degree C increments.
Yellowing and Drying zones printed on thermometer face.
Metal construction with spirit filled glass thermometer tube.
What to expect from your Home Tobacco
With the Home Tobacco Kiln, anyone who has a garden
can now process some of the finest tobacco possible. Home
cured tobacco is free of the thousands of chemical additives
included in commercial cigarettes and the delicious, full
tobacco flavor cannot be compared with anything on the market
On average, you can expect to cure a little over 2 kilos (
about 5 pounds ) of tobacco at a time over a 3-4 week
Each commercial king size cigarette usually contains a
little less than a gram of tobacco each. This means that you
can expect to cure enough tobacco for about 2,500 cigarettes
The kiln can be used continuously, meaning that you can start
curing a fresh batch of tobacco the same day you remove a
cured batch. You can kiln cure tobacco that has been air
drying for months. We mention this because you may wish to
cure tobacco for your neighbors or community and recover some
of your cost for the kiln. If you do charge to do this, make
sure you abide by your local, state and federal laws.
How much does it cost to produce a carton of cigarettes
better than store brands? We get asked this a lot, and here
is a general answer:
1. In order to start processing your own tobacco, you will
need the following equipment: A kiln, a cutting machine, and
a rolling machine .
2. Once you have these items and your first crop of
tobacco, all you will need to purchase for cigarette
production is flavoring, filters and papers. If you use a
rolling machine that uses filters, the cost of filters and
papers will run about $5.85 a carton. Adding flavoring ( we
strongly recommend this ) will add about a $1.00 to the cost
or a total of just under seven dollars a carton for filter
cigarettes, or just under five dollars a carton for
3. We did not include the cost of the kiln, cutting
machine and rolling machine as this should be absorbed over
the length of time you process your tobacco. If you currently
pay $25.00 a carton for cigarettes, and smoke a carton a
week, you would realize a savings of about $936.00 a year (
probably more since you will not be paying you local and
state taxes on this as you do store bought cigarettes ).
Of course this savings will only get larger each year,
because prices are only going to go up on cigarettes, not
We must stress that the real savings is to your
health, as you will not be consuming the thousands of
additives that are added to commercial brands.
How to use the kiln for Herb Drying
Kiln drying is the fastest, most efficent way to dry
herbs. You should never use a microwave oven to dry herbs, as
this can ruin the oils inside the herbs.
Herbs should be collected just before they bloom. Collect
herb leaves in the afternoon after all dew has dissappeared.
Make sure to shake herbs and remove any insects, dirt, etc.
It is preferrable not to wash herbs, but if you must, lightly
rinse herbs and spread leaves to dry until all visable moisture
Place herb leaves lightly into cotton gauze bags or
pillowcase and set on top of the mesh tray at the bottom of the
Leave the top lid of the kiln blocked with something so that
the lid will not completely close, but instead leaves about a
one inch gap at the front of the kiln when the lid is closed.
This is for moisture release. Plug in the kiln and let set for
12 hours. Then remove the bag(s) of herbs, stir the leaves so
the leaves that were in the center are now on the outside, and
place back into kiln.
Inspect and stir leaves every 12 hours until leaves are dry
and crisp, they are now ready for use. Small herb leaves can
dry in as little as 24 hours, larger leaves may take 2 days or