The document describes the development of a bicycle pedal. It discusses the materials, features, and manufacturing processes for various pedal components. The pedal body is made from medium carbon steel through casting or milling. Holes are drilled and threads cut on a lathe. The cog wheel is made from low carbon steel through punching, rolling, drilling, and milling operations. Other parts like the pedal arm and axle connectors are also made from low carbon steel through stamping, drilling, and other machining processes. Spark testing and other material tests are used to identify the steel grades.

1. .
faManufacturing Mini Project of
Development of Bicycle Pedal

2. INTRODUCTION
When we go through the history of travel and transportation the bicycle plays a major role. Mankind;
with the development understood the uses of the wheel and one of the foremost inventions which still
prevails with many differences is the bicycle.
There are several parts in the bicycle and amidst it the pedal plays a vital role. It is the part which the
rider gives the power to ride it. When we consider about the development of the pedal we can see a wide
variety in the pedal. In early times the pedal was made totally out of metal and it was not a very efficient
equipment.
But with the development of the technology not only the bicycle but the pedal too came a long
journey. They nowadays use the latest technologies and are very advance when comparing to the older
pedals.
Another one of the most important part is the cog wheel of the bicycle. It also came a through a
number of developments and we can see very advanced cog wheels nowadays.
Through this project we try to understand and investigate the features of a bicycle pedal and
the cog wheel and how we can develop them. Apart from that we came to know the processes that we
should follow to manufacture the pedal and the cog wheel of the bicycle.
Modern Pedals and Cog Wheels
Early day bicycle

3. PEDAL BODY
Modified bicycle pedal body has following features.
1. Smooth surface finishing
• Milling
• Boring
2. Drill holes
3. Inner thread cutting
The modified bicycle pedal body has a shape like as following.
There is a big hall at the middle in the cylindrical shape part to connect with the pedal
taper axle and another four halls with threads to attach the pedal cover to the pedal body.
There are two methods that can be make a pedal body. They are, by casting and milling. in
casting method, casting block is used to get an outer shape of the pedal body. Then we can
drill the hall in the casted part and then by using boring method we can get perfect hall that
cannot get by using drill. Finally, we can get perfect surface by using surface finishing
methods.
In milling method, we have to make pedal body as two parts. The cylindrical part and the
outer attachment parts have to make separately by using medium carbon steel.
Make a cylindrical part
• Turning Process
1Middle part of the Pedal

4. First we have to cut the work piece for our necessity length. Before leveling the flat
surfaces of the cylinder we have to fix the work piece and cutting tool on to the 3-jaw chuck
and to the table consecutively. After that, by using turning process we can level and smooth
the flat surfaces of the cylinder. Cutting speed must be maintaining between 80-120 rpm.
Here, we must be using cutting fluids while cutting. Again the turning process can be
performed to remove the external spare parts until getting our necessity diameter. To cut the
medium carbon steel, we must be use cutting tool material as more strength than the medium
carbon steel. Therefore, we can be use high steel carbon tool as a cutting tool in this process.
• Drilling and Boring Process
The hall can be drilled by using drill machine. Before the drilling we must mount the
drill bit in to the chuck or Morse taper. then we have to drill a hall step by step. That means
first we have to drill a hall by using small drill and then step by step we have to increase the
dimeter size of the drill bit. Remember that, before the drilling we must be attach the work
piece on to the table. Here, the hall diameter must be a little less than our necessity diameter.
The hall of the cylinder must make very smoothly and accurately because balls of the pedal
are rotate with the touching inner surface of the cylinder. Work piece must mount to the chuck
and cutting tool must fit to the tool holder. The feed rate of the cutter bit must be maintaining
about 550 sfpm (surface feed rate per minute). Remember that, cutting fluid must be use while
drilling and boring.
Drilling Boring

5. Make attaching parts (joints)
• Milling and inner threading process
First work piece must be mount to the table of the milling machine. Then we can be
cut the work piece by using milling process. After milling, we can be cut inner threads in the
attaching parts by using lathe machine. Here we have to use inner thread cutting tool to cut
the inner threads. So, feed rate must be maintaining as required. All above processes are done
by with the flooding cutting fluid in to the cutting place. The separately make parts are weld
together by using arc welding method after making all parts. To get a smooth and suitable
surface, joined component’s surface must be shape by using surface finishing methods.
Inner Thread Cutting Milling

6. Middle Cylinder of the pedal
Here we are going to know about how design a sheet metal cylinder of bicycle pedal. First of all we
have to identify the material which is used to made it. We were able to see this material has shining
and then we concluded that it was some kind of metal. further this part was hit on the ground and it
emitted deep sound with echo. It confirmed that it is a metal. Then we did spark test to the part and it
reacted. It is shown below. According to the spark test, we could conclude that this part was made by
using the medium carbon steel.
Machining process
Now we have to pay our attention how this cylinder was produced. The medium carbon steel sheet
metal was taken and then relevant dimensions were marked. Then fold lines were marked and folded.
Then seam was welded. Then using the grinder, we could get good finishing that part.
spark test of cylinder

7. Metal supporter for rubber part
Here we are going to describe how produce another part of the bicycle pedal. We can introduce it as a
supporter for the rubber part of the bicycle pedal. When we looked at this, we were able to identify this part
was produced by using some kind of metal. Further, this part was hit the ground and it emitted deep sound
with the echo. That result confirmed that this was a metal. Then we had to identify the type of the metal. So
we did the spark testing for it. According to that testing, it said that this metal part was made by using the
medium carbon steel.
spark testing for metal support.

8. Machining process
We could see that this was made by using the sheet metal. This type of sheet metal was produced by
rolling process. The thickness, we can control. Using the dimensions, we can scribe the outlines
lightly. Then we have to mark the fold lines. With the scriber and the steel ruler, retrace the faint
outline, we have just scratched around the outside of the pattern. Then we cut along the fold lines.
Using the milling machine, we can able to make some hole with the relevant dimensions. Then we can
fold the sheet using a mallet. Then we can create this part following the above methods.
Rubber holder
using the above methods, we can conclude that this part was made by using the sheet metal of medium
carbon steel. (Here we did spark testing.)
Machining process
Then we should take the sheet metal and mark the lines using the scriber according to the dimensions
which were taken before. Then lines are tightly traced using scriber and the steel ruler. Then we could
cut along the lines.
Using the milling machine, we are able to make hole with the shape of circle according to the relevant
dimensions. After that shaping machine takes place. Using that we are able to get better finishing.
Rubber Holder

9. Cog wheel of the bicycle
Cog wheel support the pedal by arm and it transmit power from pedal to chain and
this chain drives the rear wheel of the bicycle.
Features
Teeth, holes
Material Testing (low carbon steel)
There are several steps that we can follow to find the material of the component.
First we have to identify the basic material used to manufacture the cog wheel. By dropping
it to the floor, it produce sharp noise. So we can say that this was made with metal.
And also we can use magnetic test to find is it a ferrous metal or non-ferrous
material. Cog wheel response to that. So that this material is ferromagnetic.
Here, cog wheel is coated with paint. So the naked surface cannot be seen directly.
We made some scratches to emerge the metal surface of the cog wheel. That surface is light
gray in colour. So we can get an ideal of it as low-carbon steel.
In the spark testing, it produce large volume of stream of sparks, relatively higher
length. Colour of the spark is dark yellow (straw colour) and at the end some of the sparks
got white-straw colour. So we can say that this was made by low carbon steel.
Spark test for cog wheel

10. Machining
In industry there are several steps to make the final cog wheel. The entire wheel is
made from iron-carbon sheet. The material is low carbon steel, so the formability and
weldability are best, due to the low carbon content of the material.
To get the shape of the wheel, use a material plates that in thickness in desired size
and make pieces from it to desired shape. Here use punching mechanism to make desired
shaped parts. After that use process piece goes in rolling process that reduce the thickness
for the exact size mentioned in the drawing.
To get the bend shape in the wheel, use punch and die. Hold the work piece on the
die and using desired stamp can make desired shape.
To remove material from the center part of the wheel use drilling. First mark the
centers of the holes. By removing materials, lighter weight and also reduce the material
amount that need to manufacture the product. To hold the work piece, can use clamps.
Using clamps, the metal piece can hold in the work bench of the drill. Here can use several
types of drill bits to make hole. To make large radius holes, use boring tools.
To make teeth on the wheel use milling operation. For that wheel can hold in the
milling machine using 3 jaw chuck and wheel is mounted on the chuck.
To harden the tip of the teeth, gear teeth must undergo case hardening. To that heat
only the tip of the gear teeth and cool down the gear teeth.
Other than that whole wheel can be made using die and the holes can be made using
punching operation.
There is no need of surface finish because it is not made using casting. So surface
finish such as polishing, lapping are neglected.
To avoid the corrosion the whole wheel is coated with paint and rather than the base
material there will be small amount of titanium and nickel to get extra strength and corrosive
resistive.

11. Fitting Bolt
This component is used for fit rubber part to the pedal. It contain screw threaded part
and head. Mainly the head is not like standard screw head.
Features
Threaded part, head
Material identification
With primary observation like it gives sharp noise. And also it reply to the magnetic
test. So we can say that this material is metal and also it’s ferromagnetic. Using visual
inspection it has dull gray. So that it is steel.
With the help of the spark test it gives large volume of stream relatively lengthy.
And also the colour of the spark get straw and at the end white colour. So we can say that
this is mild steel component.
Fitting bolt
Spark test for fitting bolt

12. Machining
First we get the raw steel spindle and using piling we get desired size of the spindle
because casting processes are not appropriate.
Bolt head and is not in standard geometrical shape. So we can say that this head is
made by upsetting. To that first heated one end of the spindle until it get red colour. And
then by hammering to that end while the hot end on the anvil and perpendicular to the anvil.
Putting that hammered face into the hole can get desired size. After By doing this several
times until we get desired shape. Then grinding the surface of the head we can get finished
head.
Then work piece cut into the desired length. Then to thread cutting we can use
tapping operation by holding it using wise.
Another method is we can use lathe machine to thread cutting. There can use 3 jaw
chuck and thread cutting tools.
There is no need of surface finish because this part is totally in the rubber
component. To avoid the corrosion, there can be added nickel platting on the nut.

13. Arm of the cog wheel
The arm of the cog wheel is the part which connects the pedal to the axel of the bicycle. The arm is
fastened to the cog wheel by welding and the pedal can be replaced since it is fixed using a thread. It is
totally made out of bulk metal and there were several features which can be detected easily. There are three
holes and one hole consists of internal threads.
Material Testing
When we consider about the materials used to produce this arm we must first consider about the
visual inspection of the part. The part was covered with a black coloured paint. By scratching the paint we
could identify that the part consists of metallic material and the whole component was made using the same
metal. When we drop a part of it to the floor it gave a sharp sound. When we check the magnetic features of
the part we could understand that it reacts positively and made us to conclude that it is made of ferrous
material.
The next testing that the arm was subjected was the spark test. By spark test we could identify the
material that is used to produce the arm of the cog wheel.
As shown above we can see a little middle bursting in the sparks and the number of sparks that emits
is not a very big number. Mostly bursts occur at the end of each spark. The sparks are lengthy in comparison
and the colour is light orange and yellow mixed colour. By comparing the sparks with the metal identification
tables we came to the conclusion that the arm is made of medium carbon steel.
Spark testing of Arm of the Cog wheel

14. Machining process
When we consider about the machining processes followed to manufacture the arm of the cog wheel;
we have to use a die to get the relevant shape of the arm. Here we do casting and by pouring liquid metal in to
the die we can get the relevant basic shape of the arm. Since the cast iron doesn’t have enough strength and
shock resistance the medium carbon steel is used as the casing material.
Then we have to subject the arm to heat treatment which increases the machinability of the material
which called annealing.
After that we have to clamp the arm on a wise and then we have to drill the holes of relevant radii. For
this,
• At first we need to mark the center of the whole using the center punch.
• Then we can use a drill bit on small diameter like 5 mm to drill a hole in the bulk piece.
• Then we can increase the diameter by boring.
• For this we can use the lathe boring and the tool is made of high speed steel.
• The hole which has a diameter of 6.6 mm we need a rpm about 8000 and the cutting speed about170.
The feed rate per revolution is nearly 0.1
We have to drill three holes and then we have to do threading using the lathe machine. For that we have to
mount the work piece on the four jaw chuck and then using the inner thread cutting tool. We have to cut the
inner thread 1 mm pitch and the speed of threading is about 8-9 m per hour and the feed should be 0.4 mm.
We have to use the operation of turning of lathe machine for this.
Next we can remove the work piece from the lathe tool and then we have to mount the work piece on
the shaping machine to get the required surface finish. Finally, we have to use the welding principle to weld
the arm with the cog wheel. For this we use forge welding. Here we heat both the to about 1300-14000
C and
by hammering we can fasten them by letting them to occur plastic deformation.
After all we have to clean the combination and then we have to apply the specific coating in order to
protect from corrosion.
For further developments we can replace the material with aluminum alloys, carbon fiber, titanium or
any material which is lighter in weight and higher in strength.

15. The connector of Axel
There are two connectors for a pedal and they come in the two ends of the pedal which bears the axel.
When we consider about the shape of the connector it is a thin sheet of metal and has three holes as to be a
round one and two square type holes. It is 2.3 mm of thickness and width is 6.5 mm.
Material Testing
When we consider about the material testing first of all we’ve considered about the conclusions that
we can get by the visualization of the component. It is crystal clear that the component is made out of metal.
When testing the sound of the component by dropping it and letting it to hit the ground, we can further
confirm that this is made out of metal. By testing for magnetic features we can understand that it is a ferrous
metal since it showed magnetic features.
After recognizing that it is a metal we’ve done the spark test for the component
By the spark test since the sparks doesn’t have any bursts in the middle part and due to the colour and
the shape of the sparks we can conclude that the steal used is low carbon steel.
Spark test for the connector of the axel

16. Machining process
When we consider about the machining process of the connector of the axel we can understand it is
basically made out of sheet metal which is of a thickness of 2.3 mm. By taking the sheet metal we can use a
die and stamp to get the relevant basic shape as we needed. After getting that shape we can drill the hole by
mounting it on the stage of the pedestal arm drill.
After that we can make the two square shaped holes by the chisel and the hammer. Then we can use
the surface grinder to make the finishing. Since there is a magnet to hold the work piece we can easily
hold the work piece and can get the required finishing. After all we can subject the work piece to the heat
treatment and we can get the strength required by that process.
Filleted Nut
The tapered nut is the nut which helps to room balls in the outermost end of the pedal. It has a filleted
one side which fastens with the end cap and the space amidst them is used to fix the balls. The nut is a one
which consists of 6 sides and it is 6.12 mm of height while 3 mm is of hexagonal in shape. The other part
consists the fillet. There is a taper in the hexagonal shaped end.
Material Testing
As above we can easily identify that this part consists of metal and the sound it releases when hit with
the flow confirms it. It also gives positive for the magnetic testing.
When we consider about the spark test we can identify that this also made out of the stainless steel.
Machining Process
This part consists several machining processes. We can see hot milling, drilling turning and also cutting.
To produce this part first of all we have to use the milling machine and cut the metal circular rod in to a
hexagonal shaped rod. Then we have to cut the required part from the hexagonal bar. For this we have to use
power saw.
After that we need to chamfer the other end of the nut. For this we can use lathe machine. This fillet
shape is required to give the path to the balls to run.
After that we have to cut the threads using the tapping tool by mounting it on a wise. Finally, we have
to do the heat treatment to give the required strength to the nut.

17. Bicycle pedal axle
This component plays a major role in bicycle pedal mechanism. This axle makes the connection
between bicycle paddle arm and bicycle paddle. The bicycle paddle is free to rotate around this axil. This axle
consist of two threaded parts at it’s two ends to connect this axle to paddle arm and paddle. This axle has
made in four sections in order to reduce material give sufficient strength to the axle. The ends of these
sections have fillet to reduce the stress concentration.
Material testing
Visual inspection is a main method to testing the material . This method help to identify which
material have been used in manufacturing that component. Here in pedal axle we can shiny steel color. When
we drop this pedal axle on the flow it gave a sound which less sharp compared to mild steel. by considering
this feature we can assume that this has made from stainless steel which is a combination of steel ,chrome and
nickel.
2Axel of the pedal

18. Spark test is a good method to identify the materials. Specially this test helps to identify ferrous
materials. In this test we apply a sample of our testing material in to a grinding wheel and observe the sparks
comes from it. Then we can compare that sparks with a chart of sparks from known samples. According to that
spark test it is clear that the spark of our testing sample is similar to stainless steel samples.
So according to visual inspection and spark test we can say that pedal axle has made from stainless
steel.
Machining process
Let’s consider we have stainless steel bar we have to manufacture this bicycle pedal axle from that
steel bar. We can use lathe machine and milling machine to that operation it is economical and time
consuming.
First we have to cut this stainless bar in to our axle length for that we can use a metal cutting panel
saw . there can be errors happen in this operation. They are the cutting surfaces are not perpendicular to the
axis of the axle. To correct that error we can use the facing operation. For that operation the work piece can
be mounted on the 3 jaw chuck attached to the axle. When we do this facing operation we should care of the
length of the bar otherwise it could be smaller than required axle length.
Lathe machine
Milling machne

19. In our pedal axle we can see different size of diameters. We can use turning operation to make them.
For this operation also the work piece can be mounted on the 3 jaw chuck attached to the axle. When we
consider from one end the diameter is increasing from 7.17mm to 8.185mm then 9.64mm and 15.47mm
finally the other end to 13.863mm. then we can use tapering process. We uses that tapering process to
reduce the stress concentration around turned ends. In our work piece we use tapering between 7.17mm
section and 8.18 mm section and between 8.18mm section and 9.64mm section. We also have to fillet the
end between 15.4mm diameter section and13.83mm diameter section. We can use lathe machine for this
operation . we do this operation as this place keep in touch with bicycle balls. This taping operation should
done carefully and smoothly.
Then we have to cut thread in both ends. The pitch of the thread is 1mm. there is a stranded of thread
cutting related to the diameter of the work piece. Before thread cutting the gear system of the lathe machine
to relevant speed should be done this speed depends on pitch of the thread cutting. This is a very important
fact as that thread cutting should be done correctly. These thred cutting can check by screw guage.
Finally we can use milling operation to 15.47mm part in two opposite ends. And cut the key lock in the
threaded end. For every above operation lubricant oil is used.
Thread cutting
Milling operation

20. End Cup of the Axel
When we consider about the axel the end cap plays a vital role. It is a must to have an end cap since it
paves the way to act as a path to the balls to run. This is totally made out of sheet metal and the contact
between the pedal and the axel is done by the balls which are roomed inside the cap.
Material testing
Visual inspection is a main method to testing the material . This method help to identify which
material have been used in manufacturing that component. Here in end cap of main bar we can shiny silver
color. When we drop this pedal axle on the flow it gave a sound which is similar steel. by considering this
feature we can assume that this has made from type of steel. But using only these two tests we can’t say that
from what material this component has made from

21. Spark test is a good method to identify the materials. Specially this test helps to identify ferrous
materials. In this test we apply a sample of our testing material in to a grinding wheel and observe the sparks
comes from it. Then we can compare that sparks with a chart of sparks from known samples. According to that
spark test it is clear that the spark of our testing sample is similar to medium carbon steel samples.
So according to visual inspection and spark test we can say that pedal axle has made from
medium carbon steel.
Manufacturing process
We use casting method to manufacture this product. First we have to make a mold to manufacture
this end cap then by using that mold we can manufacture that end cap of main bar after this process we can
use a heat treatment to make hard this end cap.

22. Middle Cylinder of the pedal
Here we are going to know about how design a sheet metal cylinder of bicycle pedal. First of all we have to
identify the material which is used to made it. We were able to see this material has shining and then we
concluded that it was some kind of metal. further this part was hit on the ground and it emitted deep sound
with echo. It confirmed that it is a metal. Then we did spark test to the part and it reacted. It is shown below.
According to the spark test, we could conclude that this part was made by using the medium carbon steel.
Machining process
Now we have to pay our attention how this cylinder was produced. The medium carbon steel sheet metal was
taken and then relevant dimensions were marked. Then fold lines were marked and folded. Then seam was
welded. Then using the grinder, we could get good finishing that part.
spark test of cylinder

23. Metal supporter for rubber part
Here we are going to describe how produce another part of the bicycle pedal. We can introduce it as a
supporter for the rubber part of the bicycle pedal. When we looked at this, we were able to identify this part
was produced by using some kind of metal. Further, this part was hit the ground and it emitted deep sound
with the echo. That result confirmed that this was a metal. Then we had to identify the type of the metal. So
we did the spark testing for it. According to that testing, it said that this metal part was made by using the
medium carbon steel.
spark testing for metal support.

24. Machining process
We could see that this was made by using the sheet metal. This type of sheet metal was produced by rolling
process. The thickness, we can control. Using the dimensions, we can scribe the outlines lightly. Then we have
to mark the fold lines. With the scriber and the steel ruler, retrace the faint outline, we have just scratched
around the outside of the pattern. Then we cut along the fold lines. Using the milling machine, we can able to
make some hole with the relevant dimensions. Then we can fold the sheet using a mallet. Then we can create
this part following the above methods.
Rubber holder
using the above methods, we can conclude that this part was made by using the sheet metal of medium
carbon steel. (Here we did spark testing.)
Machining process
Then we should take the sheet metal and mark the lines using the scriber according to the dimensions which
were taken before. Then lines are tightly traced using scriber and the steel ruler. Then we could cut along the
lines.
Using the milling machine, we are able to make hole with the shape of circle according to the relevant
dimensions. After that shaping machine takes place. Using that we are able to get better finishing.
Rubber Holder

25. Developments of a pedal casing
To improve the contact and avoid slipping, roughness of the outer part of the pedal is
increased and material is changed into metal from the rubber.
For the metal case can use aluminum, to reduce the weight and increase the strength.
And also there must be gripping parts in the pedal in order to avoid slipping.
To manufacture this can use a metal sheet and in the same sheet, can cut using metal
cutting press or using metal cutter. After that using milling machine or a lathe machine drill
holes. To maintain better grip use clamps and using different types of drill bits can use holes
we need.
In the middle of the casing there is material removing parts because to reduce the
material amount and also to reduce the weight of the pedal.
The grips can make using milling machine and lathe machine. After making the
shape in metal, must be bent to the specified dimensions. For that can use anvil in that shape
and hammer in machine shop. For that method the material will damage so the process must
be done under specified working skills.
After that drilling the holes in the required position of the pedal is needed and for
that can use drilling machine. For that work piece must clamp in the drilling bed using
clamps.
After that using lathe machine do thread cutting that need to fit the outer part to the
middle part of the pedal.
Developed Pedal Casing

26. Development of the Cog Wheel
When we consider about the development of the cog wheel we can use a plastic cover which
would cover the wheel set of the cog wheel. This cover helps to minimize the contact of the rider or his/ her
clothes with the cog wheel.
As we know the bicycle chain runs on the cog wheel. So it is a must to have this cover since when riding
the bike if there is no any cover like this then there is a chance to get clothes dirty or to face with unexpected
accidents.
So to reduce this we’ve designed this part which is made out of plastic which looks as follows. We had
to do a little difference to add this feature to the cog wheel. For this we’ve made five internally screwed pillars
of 7 mm in height and we had to design the nuts which suits for that too.
To make the plastic component we can easily make a die and pour the liquid plastic in to it. After
removing the die, we can modify as necessity.
When we consider about the threaded cylinders are made by lathe machine. We can mount the work
piece on the lathe machine and can remove the unnecessary material by turning. Then we can mount
them on the wise and can drill them. After that we can use tapping tool to cut the thread. Finally, we
can weld them to the cog wheel using the oxy acetylene welding.
Developed Cog Wheel