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How To Make An Ox-Bow

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An ox bow is made out of wood that can bend
without cracking. I always use hickory. (Some people use walnut.) A
freshly cut tree will be the best for bending. You soften the wood
by steaming it. Freshly cut wood doesn't have to be steamed more
than twelve hours.
If you are working with dry wood, I don't know
exactly how long you would have to steam it in order to bend it, but
it would take a lot longer. Even then, the chances of the wood
splitting when you bend it would he much greater.
Selecting the Wood
So try to find a live tree which is perfectly
straight for a six-foot (1.8 m) section and about six inches (15 cm)
in diameter. It is very important that the section does not have
knots in it. Within that six-foot section, at least three feet (90
cm) in the middle should be free of knots or even bird pecks.
Sometimes when a tree is young, birds peck at
it and a blemish remains which grows over and makes a bump like a
little knot. It causes a definite imperfection in the grain of the
wood. If you try to bend a piece of wood where there is a bird peck,
the wood is likely to split. You are going to split this log
lengthwise into six or eight pieces depending on the exact size of
the log.
There might be a bird peck or knot on one side
of the log, but on the opposite side you might get a good section.
Knots are all different. Sometimes they go deep into the wood or
sometimes they are just superficial. The more you work with trees,
the better you can judge by looking at them how deep the bird pecks
or the knots go. After you split your log into sections, you will be
able to see where the knots are and how deep they go.
Splitting the Log
I use small wedges to split the log. First,
split it in half. Then split it into sixths by splitting the halves
into three sections each. You need at least three wedges to do this
properly. Your ox bow, when it is finished, will be one and a half
inches in diameter (3.8 cm) at the widest point. So, to start with,
the outside edge of the section should be at least 2 1/2 inches or 3
inches wide 9 (6.3 or 7.6 cm).

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Outside edge of section
should be 2 1/2 to 3 inches [6-8 cm] wide.
The stick initially gets hewn with a broad
hatchet until it is almost to its right dimensions. This hatchet is
a small version of the broad axe which I described in the
yoke-making article. A broad hatchet has one flat side which makes
it ideal for hewing.

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This is a Broad Hatchet.
One side is flat, which makes it ideal for hewing.
The outside edge of the stick with the bark on
it should be untouched. We want to leave the bark on to help keep
the bow from splitting where it bends. The bark will always stay on
if you handle the piece of wood properly. As you can see in the
photos, the outside edge of the bow has the bark on it and all the
carving is done on the sides and the inside.
We have two-inch (5 cm) holes in our yoke so
we make the bows about 1 1/2 inches (3.8 cm) at the top. We found
that most of the stress on the bows is right below the yoke. When a
bow breaks, it is always at that spot. After the bow passes through
the yoke, its depth is tapered down to about one inch but the width
remains the same. There is little stress on the lower portion of the
bow.
Hewing the Stick

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Progression of hewing the bow stick.
Hew the stick until it is just a little bit
oversized. (Note drawings.) Don't go too close to your lines because
the hatchet is a little bit crude and you might dig it in too far by
accident and ruin the bow. Use an outside caliper often to verify
that you aren't taking off too much or too little.

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This is an Outside
Caliper, used to take dimensions of the diameter of round surfaces.
When you have finished hewing the bow, you
should make your final decision exactly where you are going to bend
it, and mark the spot. Since you have a six-foot stick and the bow
need only be five feet (1.5 m) long, you have one foot of leeway to
choose the best spot for the center of the bend, based on the
quality of the wood. Any imperfections in the wood should be kept as
far from the bend as possible. If the bow splits when you bend it,
it is useless and you have wasted all the valuable time you spent in
preparation, so be careful at this point to use your best judgement.
Shaping with a Drawknife
The final shaping of the bow is done with a
drawknife. You can put your bow stick in a vice and shave it down to
exactly the size and smoothness that you want with this drawknife. A
drawknife should be used with the beveled edge down, facing the
wood.

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This is a Drawknife. Note the inset showing the
beveled edge.
Your shavings should be long and thin if you
are using the tool properly. The old gentleman who taught me to make
bows and yokes once said, "You can tell a man by his shavings." In
other words, the longer they are, the better the man.
Keep using the caliper to check your work. Be
careful to use the drawknife with the grain of the wood so it
doesn't dig in and make notches. You want the inside of the bow to
be very smooth because it will be constantly rubbing on the ox's
neck. The drawknife must be kept very sharp to be effective. After
you are done shaping the bow with the drawknife, then you can smooth
it with a wood rasp and then sand it.
Steaming the Bow
When it is time to steam the bow, we take an
oval shaped copper kettle approximately two feet long and one foot
wide. Have the kettle over some constant source of heat like a gas
stove. When the water is boiling and steam is coming up, then lay
the bows across the top with the bark facing up. You can steam two
bows at a time.
Cover the top of the pot and the bows with
burlap sacks to hold the steam in. Be careful not to let the edge of
the sacks hang down near the flames and catch on fire. They should
just cover the top of the pot so that most of the steam is contained
although some steam escapes through the sacks. Steam the bows for
about 12 hours to be safe.
The exact time necessary depends on your wood.
If it is really freshly cut wood, that certainly shortens the
steaming time. I have even heard of people bending green hickory
wood without steaming it at all. But I wouldn't try that. Whenever
you steam the bow, the bark will come loose. But since we are only
steaming about two feet of the bow, right where it gets bent, all
the rest of the bark adheres to the wood nicely when it is steamed
in this way.
A piece of wood can be steamed much quicker if
you enclose the whole thing in a pipe with steam coming in. But the
result may be that the bark comes off the bow. We have a steam
boiler in one of our buildings. We put a shut-off valve at one of
the steam ports and fix a pipe large enough to contain one ox bow.
The pipe is connected to the steam port with the bow inside it and
then capped.
If the bow is left in there for twelve minutes
with the steam at six pounds of pressure, it can then be removed and
bent and the bark will usually stay on. We found that if left for 15
minutes the bark would come off. More power is required to bend the
bow using this short high-pressure method than when using the slow
method with the kettle. However, the results were consistently good.
Even when the bark came off, nine out of ten bows held up under
normal service.
Bending the Bow

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This is the Form for
bending the bow. For older oxen, widen the form to compensate for
their larger necks.
A bow should be bent immediately after it is
removed from the steam. If you let it sit out in the open air, it
will lose its softness very quickly, so you must have your form set
up very near the steaming operation. The form must be bolted or
nailed onto a solid workbench. The form is pictured above.
At the top you can see that the bow is wedged
in very tightly. That is very important. Otherwise it will buckle
right at the mid-point. That is the biggest stress point, right at
the middle of the bend. The bow must be bent gradually. There are
different holes in the form and as you bend each side of the bow,
you put the pegs in to hold it in position.

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Here is how the steamed bow stick is bent on the
Form.
Depending on how thick your bow is, you may be
able to bend it by hand. Bend one side until you pass a peg hole and
put the peg in. Then you can let go and bend the other side to its
corresponding hole. In the photo I started the bend with two chain
binders. I put a chain on both ends of the bow, and I gradually
cranked the two ends together, switching from one binder to the
other. When the bend was half done, I just pushed the bow in the
rest of the way by hand. But don't do it all of a sudden. Do it
slowly. This will minimize the chance of the bow cracking.
Once the bow is bent all the way around the
form and the pegs are holding it in place, then take some wire and
wrap it around the ends of the bow to hold it in place. Remove the
bow from the form and leave it wired up. You can use the bow the
next day if you need it, but you must always leave it in the yoke.
Otherwise it will straighten out.
It may take up to a year before the bend is
permanently fixed. I have seen that there is a tendency for the bend
to gradually straighten out, so it is good to always keep the bows
in the yoke or wired together. If you have a yoke that you are not
using, just put the bows in the yoke and leave them there for an
extended period of time and then they will become fixed in the shape
of that yoke.
There should be a little space between the
side of the ox's neck and the bow, when the yoke is in its normal
pulling position. The bows shouldn't be right on the ox's neck. You
might want to have two different size forms. I have two forms and
now our older oxen have outgrown the large form shown in this
article. Instead of making a new form, we put shims on both sides of
the form to make the bow wider.
Bow Keys
You will have to put keys in the bows to hold
them in place in the yoke. A wooden key works better than anything.
We tried metal bolts, pins, spring clips, but anything we used was
completely inadequate and very troublesome, always falling out or
bending or wearing big holes in the top of the yokes. Finally we
started using the time-worn method of wooden keys.
Since the key must be small, it should be of
very strong wood. We found elm makes the best keys, and hickory
second. They can be whittled with a knife. Seven-sixteenths of an
inch (1.3 cm) is a minimum diameter for the body of the key.
Three-eighths inch (1 cm) keys break too easily, we found. It is a
good practice to always carry an extra key when you work the oxen. A
good key will break only in some extraordinary situation when the
oxen are acting up.

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Key hole must be drilled
perpendicular to bow stick, and must be carefully centered, about 6
inches [15 cm] from one end of the bow. Note how key will lock into
place.
The hole in the bow to receive the key should
be drilled. It should be carefully centered and made perpendicular
to the bow. We drill three
Key hole must be drilled
perpendicular to bow stick, and must be carefully centered, about 6
inches [15 cm] from one end of the bow. Note how key will lock into
place.
The hole in the bow to receive the key should
be drilled. It should be carefully centered and made perpendicular
to the bow. We drill three different size holes. First drill the
7/l6-inch (1.3 cm) hole for the main shaft of the key and then two
smaller ones below it. Then carve out the key hole so the key fits
in well.
The distance of the keyhole from the bottom of
the bow is critical and depends on the size of your oxen. If the
bows are too far down, the yoke slides back on their necks when they
pull. The effect of this is that the oxen are using the bows to pull
with instead of the yoke and the bows press up against their throats
and choke them. For our full-grown oxen, the correct distance is 22
inches (56 cm), but you must adjust the distance for your own oxen.
You should be careful not to damage the yoke
by the rubbing of the keys around the holes because there is no way
you can repair that. A good yoke, if properly taken care of, can
last a lifetime. So it is good to have large leather washers that
fit over the bow. The key sits on the washer and the yoke doesn't
get damaged at all.

A leather washer will prevent
key from damaging the top of the yoke.
It is also advisable to have extra bows when
you are working oxen and depending on their work, because there is
no way you can utilize the kind of yoke I have described here
without a good bow. Before I knew how to make bows and I was only
working one ox with a single yoke, I made a bow out of an iron pipe.
This can be done in an emergency |