Home' The Backwoodsman Magazine : Sept-Oct 2016 Contents 29
Fig. 1: Schematic of a flattening jig.
Flattening the pipe will not only allow the stresses to
be better distributed along the entirety of the bow but will
also allow you to bend the pipe into almost any shape
you desire. Bending PVC is much easier than steaming
and shaping wood, but the heating process does take
some practice (when PVC bows fail, it is almost always
due to an error in the heating/flattening process).
The steps are as follows:
1.) Mark the center of the PVC pipe.
2.) Place it on the flattening jig so the pipe’s center is
at the jig’s center.
3.) Turn on your heat gun and starting on one-half of
the pipe, slowly apply heat. Use a back and forth
or circular motion of the heat gun from the tip of
the pipe to the center. Although it is best to be in
a well-ventilated area, if you start to smell a chemical
odor, your heat gun is too close. You risk burning
the pipe, which will weaken it.
4.) Use a gloved finger every so often to test the softness
of the pipe. The pipe softening process will take
about 10-15 minutes. Do not rush. Remember this
is perhaps the most important part of the bow
making process. The pipe should be like a limp
noodle when it is soft enough.
5.) Place the shorter piece of wood on top, resting one
end on the two spacers at the center of the jig. Use
clamps to secure the two pieces of wood together,
sandwiching the soft PVC inside. This will flatten
and taper the PVC so it is thickest at the center,
the area of most stress.
6.) When the PVC pipe is cool, remove the clamps.
7.) Repeat on the other side.
8.) Once done, inspect the bow for unwanted bends.
Fix these areas by gently apply heat – not so much
that the area loses its shape – but just enough for
it to be sufficiently pliable for you bend it with
your hands. It is natural for one limb to bend a
little more than the other, but if there is gross
asymmetry, heat the thinner limb gently until the
PVC begins to puff back up. Remove the heat
when you achieve the desired thickness. Wait until
the pipe cools, then test bend the bow for symmetry.
For those that make wooden bows, this trial and
error process of making the limbs draw as evenly
as possible is akin to “tillering”.
9.) You now have a bow “blank” appropriate for any
kind of PVC bow project.
Put the bow aside for a moment and turn to the
wooden coat hanger. In reality, any piece of hardwood
will do, though if you happen to find a coat hanger that
is straight, the dimensions should be perfect. Cut off the
ends (~8′′) of the hanger to make wooden tips for the
bow (called siyahs in archery terminology). Wood is
lighter than PVC and the lighter ends allow the bow
tips to move faster, theoretically increasing the velocity
imparted to the arrow.
In order to attach the wooden tips, the ends of the
PVC pipe need to be heated until they swell back up
again. Apply heat to the ends until the PVC assumes its
previously circular shape. When the pipe is still pliable,
the siyahs can be inserted inside (a depth of 2′′ should
do). Although you can add a thin layer of glue for added
strength, it’s optional; when the PVC cools, it will shrink,
forming a tight grip on the wooden siyahs. It is impor-
tant at this step to make sure the nocks line up. If they
don’t, gently heat the PVC in the areas of asymmetry,
then bend the limbs into alignment.
One of the advantages of using hangers is that they
often have pre-cut slots that can be used as nocks. But
if your hanger doesn’t, use a saw to cut out a sliver on
each end for the nocks. Don’t cut more than half the
thickness of the siyah. Use sandpaper to round off the
edges. You can see more details in the video at
Although I added more heat to bend the limbs for-
ward just proximal to where the siyahs were inserted
(thus reflexing the bow limbs for more spring and draw
weight), you don’t need to do that. You can create a bow
that has a simpler longbow shape as opposed to the one
I ended up with.
At this point after everything cools, you can string
the bow and check its profile again using the techniques
described above to correct any remaining limb asymmetry.
Admittedly finicky and time-consuming, it’s a good idea
to try to correct misalignment now prior to progressing
to the takedown portion of the project.
Once you are satisfied with the profile it’s time to
make this bow a takedown. Cut the bow in half at the
center. Heat up the piece of 3⁄4” PVC until soft. Quickly
apply a thin layer of PVC cement over the end of 1⁄2”
piece of pipe you’ve designated as the lower limb. Then
slide half of the 3⁄4” piece over the lower limb. You will
now have a 1⁄2” PVC lower limb attached to a 3⁄4” PVC
grip that will also form the outer sleeve and connector
for the upper limb.
The top of the 3⁄4” PVC grip will still be circular so
gently heat and shape it to match the other end. Then
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