Carry Freedom Bamboo Trailer User manual

Welcome
Places that need a bike trailer
the most, often have the least
capacity to build or buy them.
Carry Freedom developed the
Bamboo trailer to allow anyone
the ability to build a strong
adaptable trailer from anything.
These plans allow a builder
to make a trailer from most
materials, with pinned joints, and
no bending or welding. Whether you
make it from titanium or bamboo,
this is a stiff light trailer. It
can be varied it in width length
and strength, and made to fold.
We are developing this project as
a non prot venture. These free
plans are funded by prots from
our western trailer sales.
Any help in developing funding
and circulating this project is
welcome.
Document Notes
This is a work in progress, so
appologies for all mistakes and
omisions. The ultimate aim is
to have a document that can be
followed and understood by most
people irrespective of language
culture or literacy. This of
course will take a lot of time
feedback and help.
Copyright of this document
belongs to its creator Carry
Freedom. Copying or reproducing
this document in whole or in part
without our prior writen permision
is prohibited, with the exception
of peer to peer distribution.
Peer to Peer distribution is
exchange of this document between
two private individuals, and is
permited on the understanding that
the document will be distributed
intact and no money changes hands.
Innovative design
The trailer’s innovative for 4
reasons.
1) The plans are free to
distribute.
2) Its simple. The trailer can be
made with very simple tools and
skills.
3) Its exible. The trailers
length width strength and
materials can be varied..
4) Its strong. The trailer
strength to weight ratio is near
perfect.
These Instructions
These instructions main aim is
to provide, basic layout and
sequences. It does not cover the
detail of how to do things as
techniques will vary depending on
the tools you have to hand and the
materials you are using.
innovating trailers
Bamboo trailer
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01

The Bamboo Trailer
This trailer is special because
no tubes need bent or welded, and
all joints may be simply pinned or
lashed. At one extreme this trail-
er can be made out of eight pieces
of green wood or bamboo lashed to-
gether, at the other titanium and
Kevlar pinned together. Either way
you can have a very respectable
stiff light trailer. Variations
in width length and strength are
easy; it will take any load you
have. Hitch it behind a donkey if
you lack a bike, or make it fold/
collapse if you lack space.
Construction
You’ll need eight lengths of ma-
terial capable of withstanding
bending and compression, tubing
or angle iron are ideal. You also
need eight “spokes” that are good
at taking tension. These could be
wire, chain, or steel strip. The
exoticists amongst could use Kev-
lar. Two bike wheels and a hitch
will also be useful.
Seven tubes are pinned or bound
together where they cross to
create the basic frame shape that
looks like a 6. This structure can
distort like a parallelogram, or
warp like a sheet of paper.
The Clever Bit
With the addition of the eight
spokes and the last tube this
oppy structure transforms into a
stiff light structure reminiscent
of a square bicycle wheel.
Imagine the square load area as
the rim of a wheel, with 8 spokes
connecting from its corners to a
central hub. Trueing these con-
trols how square and at the
trailer frame is. The arrangement
can be dished to make it atter on
the load side than the underside.
Four spokes stops the structure
from parallelograming while the
addition of another four and the
hub stops the frame warping. The
top set of spokes could be re-
placed by a at load bed.
The difcult bits
The wheels are supported from each
side by brackets attached to the
four frame tubes running front
to back. These brackets should be
attached so they have at plates
facing parallel to each other with
slots cut in for the axle stubs.
Each wheel is supported by a ver-
tical slot and a horizontal slot
allowing the ability to adjust the
wheels so they both are point-
ing in the same direction and not
touching the frame. Attach these
plates securely or else you will
have no end of problems.
This trailer hitches to the bike
at the bikes left hand rear axle
stub. This is the most efcient,
and the strongest place to hitch a
trailer. (See our Trailer science
pdf for an explanation).
The Purpose?
If anyone can build a trailer out
of practically anything with hard-
ly any tools that can do anything,
then a whole new world opens up.
The places where bikes are most
essential are the very places
with the least capacity to fab-
ricate them. This trailer allows
what bikes there are to do a more
useful job; from acting as ambu-
lances to carrying food to market.
Furthermore the building of these
trailers provides local jobs, and
helps invigorate the local econo-
my. Carry Freedom will be distrib-
uting plans for it through chari-
ties such as World Bicycle Relief.
The Potential
For the foolhardy the central tube
can be extended to create a mast
for a land sail, and there are
plenty of options left for the
more practical amongst us.
Solid Load Bed
The most obvious step to making
the trailer useful is to replace
the top four spokes with a at
load bed. Onto this most things
can either be lashed or bolted.
It is worth reading our Y-Frame
instructions to see how our box
QR works as this can be copied for
use on the Bamboo trailer.
Fabric load bed
The spokes can support a sim-
ple load bed made from fabric, or
rope could be woven between the
spokes to create a load bed. The
load bed is best supported by the
lower spokes. If it is being woven
between the spokes a single cord
should be woven in a spiral to
form the warp, then four separate
triangular panels can be woven
with the weft running from the
load bed edge to centre.
Cut Down Barrel
Remove the brace wires from the
centre and ll the void with an
old barrel, cutting some form of
access hatch into it.
Lifting Handles
The frame beam over hangs can be
extended to create lift handles.
At the simple level this provides
a useful grips to lift the trail-
er over obstacles on washed out
roads. There is no reason not to
extend the inside right wheel pole
and shortening the outside left
pole to create two long poles run-
ning forward. These are ideal for
hitching to an animal thus turning
the trailer into a cart.
Four Wheeler
A second trailer can be hitched
onto the back of your rst trail-
er, to create a four wheel trail-
er. This is probably best done by
extending the left inside wheel
beam forwards and hitching this
to the rear of the front trailers
inside wheel beam.
innovating trailers
General Notes
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02

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Parts List
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03
B3
B3
B1
TWL
B4
B5
B2
B2
T1
TWR
B1
H3
H2
H1
T5
T2
T6
T3
T7 T4
T8
B1
H1
T1
TWR
WB1 WB2& Wheel Brackets, from sheet metal.
TWL& Trailer wheels, from old bike.
T8 Spokes from wire chain or rope.
H3 Hitch Brackets from sheet metal.
B5 Beams, from metal or wood.
NB. You will also need materials
for making a load bed, and to join
all the parts together.
Fore
Aft
Left
Right

innovating trailers
Glossary
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04
Detail
Bad
Caution
Zoom
Proceed
Action/
Measure
Good
Drill,
D1,D2,D3,...
Measure,
M1,M2,M3,...
Bolt,
B1,B2,B3,...
Cut,
C1,C2,C3,...
Paint/Mark,
P1,P2,P3,...
Beams
Chain
Wire/
rope
Metal
Strip
Rod
Metal
Wood
B1 Object
B
B1 B5
T1 T8
H1
WB1 WB2&
H3

innovating trailers
Making Holes
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05
1.
1.
6.5.4.
3.2.
2. 3.
D1
P1
D2
P2
B1
D1
P1
B1
NB. Always mark the entry side of any hole, with
paint or a marker. This will be more accuratly
positioned than the exit hole. When joining two
beams the entry holes should be touching.
Beam to Beam
Beam to Plate

innovating trailers
Bolting Options
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06
Long Bolts(All).
Studs & Bindings (Wood & Bamboo).
Short Bolts(Metal).
2b.
2a.
1.
The stud locates the two beams, while the
binding prevents them separating.
Alternatively the two beams can be notched
rather than pegged with a stud.

innovating trailers
Wheel Brackets
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07
4 of. D1
D4
D3
D2
C1
C2
*AA*
*AA*
*AA*
B
2B
B
2B
4B
B
Where..
NB. You need two types of wheel bracket. One with a
Vertical axle slot, the other with a horizontal axle slot.
Each wheel is xed with one bracket of each type.
In combination the horizontal and vertical axle slots
allow the wheels to be adjusted so they are parallel to
each other. This means the frame alignment only ever needs
to be approximate.
WB2
WB1 2 of.
2 of.
C3 C3
WB1 WB1
2 of.2 of.
H1
H2
NB. D4 should be the
same diameter as the
trailer wheels axle.
NB. Most sheet dimen-
sions are measured rel-
ative to the depth of
the main frames beams.

innovating trailers
The Hitch
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08
B
B
BB
B
B
B
H1
H2 H3
D1 D1
D1
D2 D2
D3
D3
H1
H1
H1
H2
H2

innovating trailers
Wheels
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09
Axle width (AW)
BWF
BWR
TWR
TWL
BW
TW
TW
TW
TW BW
BW
BW
M1
LEFT RIGHT
C1 C2
Where AW left is greater
than or equal to AW Right.
≥
WB2
WB1
WB2
WB1
B1 B2 B1 B2
TWLTWR &
AW LEFT AW RIGHT
AW LEFT AW RIGHT

innovating trailers
Frame arrangement
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010
BWR
TW
B3
B2
B3
B1
C1
C2
C3
P1
P1 marks where the
wheel brackets will
be xed. It should be
roughly half way be-
tween the two B3’s,
or slightly to the
rear of this
position.
1) Lay the fore/aft
(B1 & B2) beams on a
at surface.
2) Lay the left right
beams (B3) over these
where you want the
front and back of the
load bed to be.
3) Lay the wheels in
position, and make sure
there is enough space
between them and B3.

innovating trailers
Frame arrangement
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011
D2+B2
D1+B1
D3+B3
B1
WB1
WB1
B1B2 B2
WB2
WB1
WB2
WB1

innovating trailers
Frame arrangement
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012
D1
B2
B1
B1
B2
B3
B3
B4
D3
D2
D4
D5
D6
D7
D8
D9
D10
M2
M1
90°
M3
M4
M3=M4
M1=M2
C1 C2 C5
C6
C4
D1+B5 D2+B6
D3+B7 D4+B8
D9+B13
D10+B14
D5+B9
D7+B11
D6+B10
D8+B12
D11
M2M1 M1=M2=2XM3
M3
AW LEFT
AW RIGHT
Place B3 & B4 on ground,
and B1 & B2 on top of them.
Bolt the Axle spacers in
place(B1-B4) rst.
B1
B2
B4
B3

innovating trailers
Spokes
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013
H1
C1
B6
90°
T1 T8
H2
H1
B1
B2
X8

innovating trailers
Spokes
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014
T1 T2
T3
T4
Tie, to form a loop
D2
D1
B1

innovating trailers
Spokes
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015
Repeat step for T3 T2 T4 in this order.
Tighten the ties until they are all tight, the load
bed is square, and B6 is in the load bed center.
T1
Repeat all steps for T1-> T4 on T5->T6,
but pull T5->T8 up rather than down.
T4
T7
T1
T8
T2 T3
T5 T6
C1
B2
B1
B3
B3
B6
B1
B3
B6

innovating trailers
Tensioning Spokes
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016

innovating trailers
Wheel Alignment
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017
M2
M1
M1=M2
90° 90°
90°

innovating trailers
Fitting to your bike
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018
3.
2.
1.

innovating trailers
The End
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019