Recommended tools and consumables:

D4 rated exterior wood glue/marine epoxy, yacht varnish, metal paint,

panel saw for cutting wood, saw for cutting metal, plane or surform plane,

sandpaper (coarse and fine), metal file, wood rasp, cutting fluid for

drill ing, 32mm drill bit for wood, HSS or cobalt metal bits: 10, 8, 6 & 4mm,

center punch, set square, measuring tape, side cutter pliers, pair of

adjustable wrenches, drill, clamps with at least 80mm reach, mallet and

hammer.

Tools for the project starting from the top, going left to right: D4

rated wood glue, yacht varnish, paint for protecting metal, panel saw,

hacksaw with 24tpi blades, surform plane (cheap tool for 'grating'

down wood surfaces), sandpaper (P60 and P150 grit), metal file, half

round wood rasp, cutting fluid (for using when drill ing metal, cools

down and prevents drill bits from wearing out when drill ing metal),

drill bits: 32mm flat bit for wood, 10, 8, 6, 3mm bits for metal (use

cobalt bits if you have the option), centre punch (for marking holes),

tape measure, side cutting pliers (for cutting and installing shifter

and brake cables), 2 adjustable wrenches (going up to 17mm, or a set

of spanners: 8,9,10,13, 15 and 17mm), drill, a set of clamps (or an

improvised clamp from wood with two bolts), plastic or leather mallet

and a hammer.

Parts and hardware for the bike: Two 20" wheels with 36 spokes and

10mm axles, a fork from a children's bicycle with 1" steerer tube (The

unthreaded section in the steerer tube should be no longer than

100mm, or alternatively the height of the wooden beam) and a full

set of fitting headset bearings. Hardware: Three M6 x 70 bolts with

two washers and a nylock nut each Twelve M8 x 60 bolts with two

washers and a nylock nut each Four M10 x 100 bolts with two washers

and a nylock nut each Two M10 x 150 bolts with two washers an a

nylock nut each Stem that fits in the steerer tube of the fork. (the

angle must be 90 degrees or less) Two rear-length (approximately

1,2m long) shifter cables and housings Two thumb shifters: front and

rear shifter (if the project bicycle does not come with them) Top

clamp from a kickstand Two front long reach calliper brakes (the bolt

must be longer 30mm) Two rear-length brake cables and housings

(approximately 1,2m long) Two wide riser handlebars (and brake

levers for one)

There are two options for the wooden frame. One is just to use a good

quality slowly grown timber beam, in size 3" x 4" or similar with

minimum dimensions of 75mm width, 80mm height and 1200mm

length. The second option is to glue laminate the beam using layers

of good quality timber on the surfaces with a core of lighter, poorer

quality timber. Such glue laminated beam will produce a stiffer and

stronger frame that weighs less than the first option. Skip the next

four steps if you are not glue laminating.

Glue laminating considerations: placing the boards in a stack should

produce a profile at least 80mm high, so choose the height of the

core board accordingly. Example: the floorboards are 20mm each, and

the core 40, which yields the required result. The width of the beam

should be no less than 80mm.

All pieces should be cut to a length of 1200 mm. For glue laminating,

sand or plane the joining surfaces even to prepare for gluing.

Use strong, preferably D4 rated waterproof wood glue.

With a brush, spread glue evenly to all surfaces that are joined.

If you don't have clamps, you can improvise some using scrap pieces

of wood that clamp together with 150mm long bolts.

Clamp the pieces together, applying pressure evenly. The more

clamps, the better the result. Recommended minimum is 6.

Strip a complete donor bicycle down. Both front and rear derailleur

can remain attached. The crankset can be left on if the extractor tool

is not available, but removing it makes the building process a bit

easier. Clean the frame and the components of dirt and grease to

prevent it from contaminating wood.

Mark and cut the the tubes as shown here, leaving approximately

100mm stumps in the top and bottom tube, and splitting the head

tube as close to the top tube as possible.

Flatten the bottom tube stump against a wooden surface with a

mallet, bending it parallel to the chainstays.

Drill a 10mm hole in the middle of the flattened stump. It is good to

file the end round like shown. File off anything that protrudes from

the bottom bracket shell and the chainstays. This includes cable

guides and the corners of the kickstand mount which are often folded

down. The bottom of the frame should be as smooth as shown in the

picture.

Taper down a 300mm section of both sides in the end of the beam,

narrowing it down to 60mm to facilitate crank clearance. If the beam

has been glue laminated, scrape off the extra glue and trim all

surfaces even.

Mark the outline for a round groove that is approximately 40mm wide

and 15mm deep. Leave a distance of 100mm from the middle of the

groove to the end of the frame. An indent will be made here to sink

the protruding bottom bracket shell into the frame.

To make the groove, a rough 'v' cut can be made with a panel saw,

and then ground round with a semi circular wood rasp or coarse

sandpaper around a piece of dowel or pipe. Once the frame can be sat

flush against the beam, project down the holes for the rear (where

the kickstand mount hole is, or approximately 20mm from the end)

and down directly from the flattened stump. It is harder to mark the

hole for the stump, so use an engineer's square (anything square will

do) to check that the alignment of the marking is right. Use the

square to project the holes to the opposing side and make sure they

align, too.

Drill one surface at a time, halfway through. When you drill the

opposing side, the holes will join. It will help in aligning the drilled

hole. First pilot drill with 6mm, and afterwards go through with a

10mm bit.

Use a 150mm M10 bolt and the top clamp of a kickstand to fasten the

frame down against the beam in the back. The front requires a spacer

block as shown. Find a suitable height piece of wood, cut it and drill

through with a 10mm bit. Fasten the flattened tube down, bolting

through the spacer block and the beam. Make sure the frame sits

straight on the beam.

When the rear of the frame is aligned and fastened, slot the cut

bottom tube over the top tube stump as shown. Rest the tube on the

side of the frame and trace its middle across the top face. Make

another line parallel to the beam its middle. Making these lines will

assist in maintaining the alignment in the hole to be drilled for the

strut.

Start by drill ing a 6mm pilot hole following the direction carefully.

Next drill with a 32mm bit, starting with a slightly milder angle as

shown to cut into the wood, and then slowly align it to the marks.

If the angle turns out squint, you can use a round wood rasp to adjust

and open up the hole a bit, so that the frame sits as straight as

possible. Disassemble the frame.

Measure 200mm from the end of the frame and mark a hole to be

drilled as shown. Project it to the other side again, making sure the

markings are aligned. Pilot drill halfway through with a 6mm bit, one

side at a time, making sure the drilled holes align. Afterwards drill

halfway through with a 32mm bit, again one side at a time.

Finish the wooden beam by sanding the all the surfaces smooth to

prepare it for varnishing. Round off sharp corners (except for the

drilled hole edges)

A minimum of 3 coats of yacht varnish will give an adequate

protection for the wooden frame when the bicycle is stored outdoors

throughout the year.

This drawing shows the placement of the holes. It is a top view,

meaning the holes marked with dashed lines are to be drilled through

from the side and the holes marked with dots are to be drilled from

the top.

The dashed lines are all drilled 10mm. The dots are drilled 8mm,

exept for the ones marked at 75 and 725: these holes are for

mounting the calliper brakes.

The measuring line on the top is for the two long tubing sections and

the measuring line on the side is for the four short sections.

Even furniture grade (at least 1.5mm wall thickness) 25mm tubing is

sufficient for this construction. Metal table frames are often a good

source for such material. Source and cut the necessary lengths: four

600mm, and two 800mm sections.

Each tube should have one perfectly square end. Use a metal file to

square them off. For accuracy, all the measurements should be done

from the square end, so mark it well in each tube.

Mark the tubing as indicated by the measuring lines. Do this identically on

the facing sides of the tubing. Also remembering to take measurements

from the same end. Be careful in getting the marks exactly in the center of

the tubing. Indent the marks with a center punch. It helps to align the drill

bit exactly, without it slipping off. Drill the holes, starting with 4mm and

drill ing larger 2mm at a time. Leave the indicated 10mm holes drilled to

8mm. They will be drilled larger later. Drill one face at a time (facing sides

should be marked identically), not all the way through to ensure that holes

do not go crooked. Take care not to drill the brake mounting holes larger

than 6mm.

Enlargin the 8mm hole, drill the marked 10mm holes in the four short

tubes that only have a single hole in the middle. The short tubes with

three 10mm holes each will be drilled later.

Mark a line through the middle of the fork crown brake hole, ensuring it is

perpendicular to the steerer tube. Do this identically on the opposing faces

of the fork.

Cut the fork legs off approximately 20mm below this line.

Drilling into a curved surface is a bit tricky. Center punch the marked holes

carefully. Align the drill bit against the surface as indicated top right. Drill

first on face at a time, and then afterwards once through the whole tube.

Drill these holes on the sides to 8mm, and the middle hole to 10mm.

Drill the middle holes of the two short pieces marked with a group of three

holes from 8 to 10mm. You will use three of the M10 x 100 bolts for this.

Clamp the fork between the two tubes, align the steerer tube exactly

perpendicular to the tubing, and fastening the 10mm bolt tight.

Next drill once through the 8mm holes in the whole assembly, going

through both of the tubes and the fork. This ensures the alignment is

right. Make sure that the steerer tube does not change alignment. Drill

through the assembly with a 10mm bit next, and bolt the sides.

Assemble the tubing as indicated, but do not bolt yet.

Drill through the pairs of overlapping tubes once to correct any

misalignment in holes. Bolt the prepared tubing together, only lightly

tightening and leaving two corners still unbolted as indicated in the next

step.

Mount the wheel axles through the 10mm holes in the middle. Clamp the

wheels by bolting the corners together. Tighten all bolts lightly.

Square off the assembly by measuring the diagonal length between corner

bolts as indicated. Tilt the assembly to correct the alignment, until both

measurements are identical.

Press the headset bearing cups into the 32mm hole in the frame. The order

of the bearings is changed in this case, so the bottom part of the headset

will now be on the top surface (right) of the wooden beam.

Attach the bicycle frame onto the wooden beam again and mount the front

cart on to the frame.

Tighten the bearings and trim off any extra length in steerer tube to fit on

the locknut.

Use a stem to make the mount for a stabilising strut underneath the cart.

Shorten the stem shaft as shown. There are two ways to make it. Use a cut

shaft as shown on the left to bolt the strut onto, or the stem itself with a

shortened shaft to hold the strut in place.

A large riser handlebar is good for making the stabilising strut. Cut it to

match the width of the cart as shown.

In this example the strut is bolted onto the mount. Align the strut and

mark holes to be drilled in the ends. Drill matching 6mm holes in the cart

frame.

Use the M6 x 70 bolts to secure the strut ends.

Attach brakes.

The box can basically be anything that is sturdy enough and you can

attach some sort of a handlebar to. An easy way is just to bolt a high riser

handlebar off a bmx bike or similar with 3 M6 bolts as shown.

Both brake handles will operate the two front brakes independently.

Altough it takes a bit of getting used to, so that the bike doesn't steer too

much when braking, it is an easy to build solution. Dual cable brake levers

and other mechanisms for splitting one brake lever to control two brakes

simultaneously are possible.

Gear shifters can be mounted in several places, like the seatpost or the

frame, but attaching them to the box may place the cables a bit in the way

of steering.

The rest is just sorting out the brakes and gears, which is pretty much

straightforward bike mehcanics. Enjoy!