Marwa Afechkar
Building a recurve bow
Rubric Learning targets
Novice
3d.3 | Translating geometric properties to dierent dimensions and/ or planes.
Recognises specific s factors (enlargements dilations) and therefor recognises similar sha
5b.1 | Planning and conducting ethical scientific investigations OR conducting/applying the design cycle process to solve problems or innovate
Sudents completes a
design cycle as its laid out
Execute design cycle
process to build a rec bow
scale s and re apes.
d
curve
Specialist Applies knowledge of scale factors and similar shapes to real life problems.
Students evaluates their
use of the design cycle
and reflects upon its
performance.
My
To put a li
since 201
for archer
opportunit
design my
that I desi bow.
My driving
But before bow ?
What type
What are
What are
inspiration for the project
ittle more context to this project, I have been practicing Archery
16. I found in archery the calm and relaxation I need. My passion
ry never stopped after joining TGS, this term after finding out the
ty the Fab Lab offered, I couldn’t miss the chance to build and
y own bow. This is my process portfolio and a “How to” guide
igned to record the process of making the skeleton of a recurve
How can I build a recurve bow ?
g question is
e starting the project; What do I need to know about building a
e of wood should I use ?
the different steps of building a bow ?
the different things that I need to take in consideration ?
The recurve bow Recurve bows are popular for their versatility. This bow got its name from its shape.
The center of the limbs curve towards the archer and the ends of the limbs curve away from the archer, which makes the bow more powerful. Its design does not require as much strength from the shooter. Recurve bows are great starting bows for those who want to get started with archery.
Learning how to make a recurve bows is one of the most important aspects of owning a well-structured bow. There is a wide variety of materials that are needed in the
The Mar Due to lack of equipment and time limit, Dan and I
characteristics that lean to the structure of a longb skeleton.
The Long bow Longbows are one of the oldest bows dating back to 1298.
It is a very simple bow made of a long curved piece of wood that is as tall as the archer. It does not have arrow rests or sights.
These bows are harder to aim and do not have the speed of a Compound or Recurve bow. It takes a lot of practice to master this bow, and it is good for those who enjoy a challenge.
rwa Bow will be building a recurve bow but with simpler
bow. We will still be using lamination to have a strong
Type of wood For almost all types of bows the key components when it
comes to choosing the wood that we will be working with i the flexibility. If the wood is not flexible enough, the bow will break.
Recurve bows can be made of several different woods, like osage orange, bamboo, red oak, hickory, ipe, eastern
The only wood that we could get our hands on was teak wood.
It has a high degree of natural durability, is moderately hard and
with low stiffness and shock resistance but an excellent decay r
and dimensional stability with a good acid resistance. Teak is a wood but it is not recommended to use teak for bows because very flexible.
is
e
.
d heavy
resistance
a hard it is not
Lamination
Now that we have our wood picked it
The lamination process is really important because it helps with the strength of the bow. Laminated wood is wood that has been cut into thin layers, then glued together with the grain running parallel in each layer. Attributes that make the laminated wood stronger than it's solid counterpart include: Disruption of the grain due to the many layers of wood.
There are 5 steps in lamination. The first part of it is just laminating the dierent strips of wood to give us one strong strip that we can work with. The first lamination will just be with glue and small pressers that will hold it together until glued and the second lamination would be to give the bow its form and add the handle part to it.
t is time to start cutting wood strips to start the lamination process.
Lamination
To make the core lamination of our bow we cut it fro
this step twice because the first time we only worke performing the first lamination.
This time we used 3 strips of about 1m69. We put the g
cleaned off the edges for it to be ready for the second s
om the same block of wood of teak. We had to repeat
ed with 2 strips and that caused it to break after
glue in between each strip and after the glue has dried we
step of lamination
Translating geometric prop
To perform lamination we need to have a mold that will press u
wood from up and down so it can hold its shape and not move
molds are made in the oven, some are designed 3D on a com
then printed, but for me considering the time limit and lack of a
equipment, I cut out the shape that I wanted a piece of wood t previously laminated (so it’s strong) and I used it as a mold.
But for cutting out the shapes that I wanted from the piece of w
had to apply various geometrical properties and apply recogni difference scales that I was working with.
perties
up the
e. Some
mputer
available
that was
wood I
ize the
Translating geometric prop To cut my mold I followed the following sketch.
My plane was the wood piece/board. I drew 2 axes (x;y) and s points accordingly to form the wavy shape that I wanted. The middle point represents the axe of symmetry. I had to cut and translate them in my plane.
In geometry, a translation is the shifting of a figure from one
without rotating, reflecting or changing its size. It is done by m
the figure the prescribed number of spaces on a coordinate pl the new figure.
My only tools were a ruler and a semi circle. I was using the ru
was conserving the same measurements and the semi circle t angles were conserved during the translation. (Click on videos to see evidence of me translating and the applied work)
perties
started putting my
those shapes twice
e place to another
moving the vertices of
lane and then drawing
uler to make sure I
to make sure the
I tried to do my translation as accurate as I could but there were
Dan and I noticed when we put the 2 pieces together. So we fix
imperfections with sand paper and there we had it. Our mold w
We too
that we
lamina
top of t
the mo
the mid
was pl
middle
Then we pressed the strip of wood tightly together and left it to laminate
e still some flaws that
xed the little
was ready!
ok the wood piece
e previously
ated and placed on
the bottom part of
old in such a way that
ddle of wood strip
laced on top of the
e of the mold
Why the first try failed and t
The first try of
main reasons
and they were
There was no
we decided to
them together
The other rea
amount of tim
total of 2 hour
What we learn succeed.
During our se
the results we
the second one succeeded.
f lamination just like previously mentioned failed, due to 2
s. We only had 2 strips of wood that we laminated together
e both very think so when the mold put pressure on them.
o strength or resistance so they just broke. That is when
o use 3 different wood strips that are thinner then laminate
r.
ason that caused the failure was that we left for such little
me in lamination between the molds. We only left it for a
rs but it should have stayed in the mold overnight.
nt from this failure was what cause the second one to
econd try we left it overnight to laminate, it didn’t break and
ere pleasing.
Now it is time to start shaping our bow, round th
I drew two center lines on the bow. one crosswise and the o
All measurements should be very carefully made as even a be reflected in the accuracy of the finished bow, so I made
circle to preserve the right angles of each point that translat
I measure the exact distance from, center to end of either fa
marked off equal distance other limb. Then I marked off bow
required width, then layer out limb tapers from end of fadeo
Then I cut away the excess limb so it is the hight that I wan
Having determined which is to be the up- per limb and whic
started rounding and thinning the edges using sand paper a
available tool then. The lines that I marked before helped m
myself throughout the sanding to not go over the line and h symmetrical, perfect shape
he edges and make the limbs thinner.
other lengthwise.
a slight error will sure to use semi
ted on the line.
adeout and
w tips for
out to bow tip.
nt.
ch the lower, I
as it was the only
me to guide
have a
When using the sanding machine it was really impor
focused and not press too hard on the bow. One tim made a bumpy on the bow that is was quite hard to
This sanding technique helped to bring everything to
give the bow its shape including the grip and the fina limbs.
(Click on video to see evidence of practicing sanding
rtant to stay
me I did and it get rid off.
ogether and
al form of the
g my bow)
THE BOW !
I oiled the bow to look shiny and smoother and let it dry. Due to time limit I couldn’t carry on with the final details of the bow like carving the grip and attaching the string. But this is still the skeleton of what each bow consists of and making was a success.
Thanks to Dan for mentoring this project !!!!!