3 axis cnc

3 Axis CNC PEC UNIVERSITY OF TECHNOLOGY

FABRICATION OF A 3-AXIS COMPUTER NUMERICAL

CONTROL SYSTEMS

By

Jeewanjot Singh (11109014)

Manjeet Singh (11109018)

Pradeep Tiwari (11109020)

Rohit Jhanwar (11109023)

Sumer Singh (11109025)

Under the Guidance of

Prof. Rahul Vaisya

Department of Production Engineering

PEC University of Technology, Chandigarh

August - November 2014


DECLARATION

We hereby declare that the project work entitled “FABRICATION OF A 3 AXIS CNC

MACHINE” is an authentic record of our work carried out at Production Department as

requirements of capstone project semester for the award of degree of B.E. Production

Engineering, PEC UNIVERSITY OF TECHNOLOGY Chandigarh, under the guidance of Mr.

Rahul Vaisya from august

2014 to November 2014.


Dated: Dec 2014 Manjeet Singh (11109018)




Certified that the above statement made by the student is correct to the best of our knowledge and

belief

Prof. Rahul Vasiya

PRODUCTION ENGINEERING DEPT.

PEC UNIVERSITY OF TECHNOLOGY

CHANDIGARH


PREFACE

This report contains the project done during our capstone project period. We realized the essence

of the Practical work. We have also understood the need of practical knowledge for a fresh

engineer along with the theoretical knowledge.

All engineering students are facing lots of problems during working in organization. Applying

theoretical knowledge only cannot solve those problems. It requires practical knowledge, which

can be helpful in future.

In this liberalized and global market, it is necessary for an engineer to have practical knowledge

in order to achieve best quality and higher production to survive in a market.







ACKNOWLEDGEMENT

‘With greater powers comes greater responsibility’

In this age of cutting edge technologies, the scenario of the race for the technology is like the

more we try to chase the horizon; the more difficult it becomes to maintain the pace. And till the

hope to overrun the horizon survives, newer technologies will keep on emerging.

“We live in an age of history where change is so speeded up, that we begin to see the present

only when it has already disappeared.” We would like to take this opportunity to thank the PEC

University of Technology for allowing us to study the final year of “Industrial and Production

Engineering” and to permit us to deliver our capstone project.

We would also like to thank our mentor Prof. Rahul Vaisya who has helped us along the

process of completing the project.







LEARNING OBJECTIVES

SHORT TERM

The short term effect of the capstone project was that we realized the importance of time. We

have to fulfil our objective within the stipulated time limit.. We have also learnt to be sharp,

precise and accurate in our work and to finish it on time to gain maximum profit. We have

learned skills such as communication, discipline etc. which are of immense importance in an

individual’s life.

LONG TERM

The capstone project has helped us in attaining practical knowledge regarding industrial machines,

processes that will guide us throughout our career. It has enabled us to have precious practical

experience that is required at various fields of industrial and production engineering.


MOTIVATION

The motivation for doing this project was primarily an interest in undertaking a challenging project

in an interesting area of research. The opportunity to learn about a new area of manufacturing was

appealing. This area is possibly an area that we might study at postgraduate level.


INDEX

CHAPTER-1 PAGE NO

INTRODUCTION

10

INDUSTRIAL USES 11

PERSONAL USES 12

TARGET FOR 7TH SEMESTER 13

TARGET FOR 8TH SEMESTER 14

DETAILED DESCRIPTION 15

CNC STANDARD SPINDLE SPECIFICATION

16

MDF MATERIAL 17

BENEFIT OF MDF 18

APPLICATION OF MDF 19

DESIGN CONSIDERATIONS 20

PURPOSE 21


OBJECTIVES 22

CHAPTER 2

FABRICATION

BILL OF MATERIAL 25

HARDWARE AND TOOLS 26-27

DIFFERENT PARTS OF THE CNC 28-29

DRILLING AND MOUNTING THE RAILS 30

ATTACHING THE TABLE LEGS 31

CUTTING THE X – AXIS LEAD SCREW 32

Y AXIS 33

PREPARING FOR THE Z AXIS 34

DRILLING AND CUTTING MDF AND RAIL 36

STEPPER MOTOR 37

ASSEMBLY 38

Z AXIS BEARING SUPPORT 39

BED AND XY ASSEMBLY 40

Z AXIS ASSEMBLY 41


TOP AND BOTTOM BED ASSEMBLY 43

CHAPTER 3

DESIGN 45

OVERALL DIMENSIONS AND GENERAL NOTES

46

Z AXIS BEARING SUPPORT

47

ROUTER BASE

48

Z Axis Rail Support

49

MOTOR MOUNT

50

CONCLUSION

65

FUTURE SCOPE

66

REFERENCES

67


CHAPTER 1

INTRODUCTION

Computer numerical control is a very broad term that encompasses a variety of types of

machines—all with different sizes, shapes, and functions. But the easiest way to think about

CNC is to simply understand that it’s all about using a computer as a means to control a machine

that carves useful objects from solid blocks of material. For example, a CNC machine might

begin with a solid block of aluminum, and then carve away just the right material to leave you

with a bicycle brake handle

CNC machines can be divided into two groups: turning machines and milling machines. A

turning machine is generally made up of a device that spins a workpiece at high speed and a tool

(sharp edge) that shaves off the undesired material from the workpiece (where the tool is moved

back and forth and in and out until the desired form is achieved). A milling machine is a machine

that has a spindle (a device similar to a router) with a special tool that spins and cuts in various

directions and moves in three different directions along the x, y, and z axes.\

Historically, you wouldn’t actually need a computer to create forms with a turning machine or a

Milling machine. Adding a computer to the mix allows you to design a product on a computer

first and then specify how the machine should cut this product. To design the product is to

produce a computer aided design (CAD) file. Then you specify how the machine should cut the

product, and the result of that step is a computer-aided manufacturing (CAM) file (or G-Code

file, or .NC file—there are many names for this type of file).

This CAM file remembers all of the operations that the milling machine must follow to cut out

the parts for the product. The computer tells the CNC machine how to build the part by

interpreting the CAM file into signals that the CNC machine can understand


Industrial Uses

Industrial applications for CNC machines have been chiefly based around the removal of metal

to create a desired form. Metal is widely used for producing almost everything we see around us,

even though these things may not be made of metal themselves. Some of the most obvious

products that are made of metal are cars. The engine block and the parts within the transmission

are directly produced from a CNC machine because tight tolerances are necessary (a tolerance is

a range in dimensioning to which the machine must adhere). However, most of the parts of a car

are not made by a CNC machine, but they have a latent connection to one. For example, how do

you make a quarter panel? There is a hydraulic press with a thing called a die to create an

impression in a sheet of metal. Most of the parts of the hydraulic press were made from a CNC

machine. The die, the part that carries the negative form of the quarter panel and that can be

replaced when design changes, was also made by a CNC machine, and then tempered for

hardening and heat resistance. Even the plastic parts of a car have some connection

to a CNC machine. Many of these parts were made from a mold that was created using a CNC

machine.

Because CNC machines have very high precision and they can provide information back to the

Computer, they are also used in dimensional testing. If a switch (probe) is fastened to the

location of the tool, it can analyze the measurements of a part that was produced.


Personal Uses

There is a large following by various hobbyists and DIYers around the globe interested in the

concept of CNC machines. Roboticists, craftsmen, handymen, home machinists, small business

owners, tech enthusiasts, backyard scientists, and artists have all discovered how a CNC machine

can open doors to new designs and more detailed creations. A roboticist, for instance, will use a

CNC machine to create the structural components of the robot with very high precision. Making

these components by hand would be tedious and very time consuming. Using a CNC machine,

the parts come out beautifully and fit together with great precision.

For the typical handyman, a great example of using a CNC machine might be designing and

making cabinets for around the house. Typically, cabinets share many of the same dimensions

and can be cut by a CNC machine over and over. Imagine cutting all of the drawers and cabinet

lids by hand! The parts are numerous and the work would be quite tedious. But with a CNC

machine, the individual pieces are cut and the cabinets assembled; no driving around looking for

the right cabinets, having to special order them, and then waiting for delivery from the home

improvement store. (The cabinets will need assembly, too, but with your own CNC machine,

you’ll find that the high cost of buying them in the store can be eliminated.)


TARGETS FOR 7th SEM

Planning and design of three axis CNC machine.

Preparation of bill of material(B.O.M.)

Purchasing material for the construction of CNC machine.

Planning & execution of outer frame of CNC machine.

Planning and execution of mechanical sub system for CNC machine.


TARGETS FOR 8th SEM

Purchasing different types of motors, circuit board, break out board.

Installation of motors housing

Designing electric circuit.

Installation of break out boards, stepping motors, drivers.

Final fabrication of CNC machine

Testing of our CNC machine.

Final improvement and changes in our project according to the result of test.


DETAILED DESCRIPTION

Working Area Dimensions (MDF base version)

Table Dimensions 24” [610 mm] x 48” [1220 mm]

Table Travel 42” [ 1070 mm]

Modifiable to max 45” [1145 mm]

Working Height Clearance 3” [76 mm]

Max Spindle Height 6” [150 mm]

Y axis travel 19" [478 mm]

Z axis travel 8" [204 mm]

Power Requirements Power Supply Requirements 220 VAC or 110 VAC, switch-selectable

As provided to the CNC Machine by

Power Supply

12 VDC, up to 4 AMPS

5 VDC, 500 mA

As provided to the CNC Spindle by Power

Supply

12 VDC

No load: 700 mA

Start Up: 600 mA

Load: 1.2 A


CNC Standard Spindle Specifications

Spindle Speed 16,000 RPM

Tool Holder Collet with spindle lock for easy changes

End Mill Sizes

(Collets provided)

1mm

3mm

3/32"

1/8"

Included Power Supply 120V AC/DC adapter with 55" [1.4m] cord, barrel

jack connection to spindle

(For use if optional CNC Spindle Control

Module not used)

Dimensions: 4 13/16" L x 1 3/8" dia.


MDF MATERIAL

Medium-density fiberboard (MDF) is an engineered wood product made by breaking down

hardwood or softwood residuals into woodfibres, often in a defibrator, combining it

with wax and a resin binder, and forming panels by applying high temperature and pressure

.MDF is generally denser than plywood. It is made up of separated fibers, but can be used as a

building material similar in application to plywood. It is stronger and much denser than particle

board.

Physical properties

Over time, the word "MDF" has become a generic name for any dry process fiber board. MDF

density is typically between 500 kg/m3 (31 lbs/ft) and 1000 kg/m3 (62 lbs/ft). The range of

density and classification as Light or Standard or High density board is a misnomer and

confusing. Density of board when evaluated in relation to density of the fiber that goes into

making of the panel is important. A thick MDF panel at a density of 700-720 kg/m3 may be

considered as high density in the case of softwood fiber panels, whereas a panel of the same

density made of hard wood fibers is not regarded as so. The evolution of the various types of

MDF has been driven by differing need for specific applications.

Comparison to natural woods

MDF does not contain knots or rings, making it more uniform than natural woods during cutting and

in service. However, MDF is not entirely isotropic, since the fibres are pressed tightly together

through the sheet. Like natural wood, MDF may split when woodscrews are installed without pilot

holes, and MDF may be glued, doweled or laminated, but smooth-shank nails do not hold well.

Typical fasteners are T-nuts and pan-head machine screws. Fine-pitch screws do not hold well in

MDF and screw retention in the edge is particularly poor. Special screws are available with a coarse

thread pitch but sheet-metal screws also work well. Typical MDF has a hard, flat, smooth surface

that makes it ideal for veneering, as there is no underlying grain to telegraph through the thin veneer

as with plywood. A so-called "Premium" MDF is available that features more uniform density

throughout the thickness of the panel.


Benefits of MDF

Is an excellent substrate for veneers

Some varieties are less expensive than many natural woods

Isotropic (its properties are the same in all directions as a result of no grain), so no tendency

to split

Consistent in strength and size

Flexible. Can be used for curved walls or surfaces.

Shapes well.

Stable dimensions (won't expand or contract like wood)

Easy to finish (i.e. paint)

Drawbacks of MDF

Denser than plywood or chipboard (the resins are heavy)

Low grade MDF may swell and break when saturated with water.

May warp or expand if not sealed.

Contains urea-formaldehyde which is a probable carcinogen and may cause allergy, eye and

lung irritation when cutting and sanding

Dulls blades more quickly than many woods

Though it does not have a grain in the plane of the board, it does have one into the board.

Screwing into the edge of a board will generally cause it to split in a fashion similar to

delaminating.

Subject to significant shrinkage in low humidity environments.

Trim (i.e. baseboards) comes pre-primed but this is insufficient for fine finish painting.

Painting with latex paints is difficult due to rapid water absorption. Most finishes appear

uneven and nail holes tend to pucker.


Applications

Loudspeaker enclosure being constructed out of MDF

MDF is often used in school projects because of its flexibility. It is also often used

in loudspeaker enclosures, due to its increased weight and rigidity over normal

plywood. Slatwall Panels made from MDF are used in the shop fitting industry.

Safety concerns

When MDF is cut a large quantity of dust particles are released into the air. It is important that

a respirator be worn and the material be cut in a controlled and ventilated environment. It is a

good practice to seal the exposed edges to limit the emissions from the binders contained in this

material.

Formaldehyde resins are commonly used to bind the fibers in MDF together, and testing has

consistently revealed that MDF products emit free formaldehyde and other volatile organic

compounds that pose health risks at concentrations considered unsafe, for at least several months

after manufacture. Urea-formaldehyde is always being slowly released from the edges and

surface of MDF. When painting, it is a good idea to coat all sides of the finished piece in order to

seal in the free formaldehyde. Wax and oil finishes may be used as finishes but they are less

effective at sealing in the free formaldehyde.

Whether these constant emissions of formaldehyde reach harmful levels in real-world

environments is not yet fully determined. The primary concern is for the industries using

formaldehyde. As far back as 1987 the U.S. EPA classified it as a "probable human carcinogen"

and after more studies the WHO International Agency for Research on Cancer (IARC), in 1995,

also classified it as a "probable human carcinogen". Further information and evaluation of all

known data led the IARC to reclassify formaldehyde as a "known human carcinogen" associated

with nasal sinus cancer and nasopharyngeal cancer, and possibly with leukemia in June 2004.


DESIGN CONSIDERATIONS

To maximize utilization of material, parts are nested as close to each other as possible. They are

separated from one another by "micro-ties" which are small width strips that hold the parts

together during the punching process. After punching, the parts are separated by vibrating them

in a shaker. The parts are known as "shaker parts" or "shake a part". This is very cost effective

since no special tooling is necessary for separating them.

Burrs are inevitable in the stamping process. The burrs are formed on the side of the sheet metal

where the punch exits. Properly maintained tools (proper die clearance and sharpening) have

burrs that are less than 10 % of stock thickness. When designing parts, the burrs should be

confined to areas that will not be exposed to handling and should be either folded away or

otherwise shielded from the user. Otherwise, an added operation of deburring needs to be done at

added cost.

Flatness/bowing can be an issue if the hole pattern is tight, and/or where excessive material is

punched out. This releases the residual stresses in the material, which causes bowing or twisting

of the part. Proper use of clamping and strippers can minimize this, as can subsequent

straightening operations. Recognizing which side the bow can occur can also allow some designs

to accept this out of flat condition by designing features that are not sensitive to this condition.

Edge conditions. Quite often, curves and other difficult features are produced by punching out

small sections at a time. This process is called nibbling. This leads to triangular shaped features.

These triangular shaped features give the edge a scalloped look. This scalloping can be

pronounced if the nibbling pitch is coarse. The amount of scalloping that can be accepted is a

function of tooling and product cost. Clamp marks are cosmetic in nature, and if objectionable,

can be so positioned to cut them away in subsequent processing.

Dimensioning. As in all part design, the designer should be aware of process strengths,

weaknesses. Datum’s should be through hole centers rather than edges of parts. This is because

edges can have tapers or roll-offs, which can skew a datum and subsequent measurement. Sound

practice of tolerancing methods such as geometric dimensioning and tolerancing are appropriate

for the dimensioning of these parts


PURPOSE

CNC machines typically replace some existing manufacturing process/es. Take one of the

simplest manufacturing processes, drilling holes, for example.

A drill press machine holes. A person can place a drill in the drill chuck that is secured in the

spindle of the drill press. They can then (manually) select the desired speed for rotation

(commonly by switching belt pulleys), and activate the spindle. Then they manually pull on the

quill lever to drive the drill into the workpiece being machined.

While this manual intervention may be acceptable for manufacturing companies if but a small

number of holes or workpieces must be machined, as quantities grow, so does the likelihood for

fatigue due to the tediousness of the operation. There are more complicated machining

operations that would require a much higher skill level (and increase the potential for mistakes

resulting in scrap workpieces) of the person running the conventional machine tool.

By comparison, the CNC equivalent for a drill press (possibly a CNC machining center or CNC

drilling & tapping center) can be programmed to perform this operation in a much more

automatic fashion. Everything that the drill press operator was doing manually will now be done

by the CNC machine, including: placing the drill in the spindle, activating the spindle,

positioning the workpiece under the drill, machining the hole, and turning off the spindle.

CNC means "computer numerically controlled" and it describes any of a number of different

machines (arbor mills, end mills, lathes, presses, multi-spindle drills, etc.) that can be

programmed to move a workpiece to a prescribed location (or locations) and perform a

prescribed operation (or operations) on it.


OBJECTIVES

Trying to reduce cost of machining process and machining time with help of our CNC

machine.

Trying to generate some difficult shape on work piece easily and with high accuracy.

Trying to increase production rate and profit with help of cheap, fast and automatic CNC

machine.

Try to prepare a CNC machine which is easy to assemble, operate, and maintain.

Trying to make CNC machine a user friendly machine.

Longer working life owing to MDF.

Can perform different machining operation with the help of different apparatus.


CHAPTER 2

FABRICATION

ASSEMBLY (SIDE VIEW)


ASSEMBLY (FRONT VIEW)


BILL OF MATERIAL (BOM)

2 MDF Board

Dimension-

Length- 8 foot

Width-4 foot

Height-3/4 inch

RAIL (1)-

Thickness-1/8 inch

Width-5/4 inch

Length-8 foot

Cut this into two pieces of length 4 foot each.

RAIL (2)-

Thickness-1/8 inch

Width-3/4 inch

Length-9 foot

Cut into-

4 pieces of length-4 inch

2 pieces of length-10.06 inch


2 pieces of length- 7 inch

Nut-24 Nos.

Dia-5/16 inch

Length-1 inch

Bolt-24 Nos.

Bearing-24 Nos.

Inner dia-5/16 inch

Outer dia-3/4 inch


Hardware and Tools

Following is a list of our tools, with a few photos for clarification:

• Table saw: This is useful for cutting long lengths of MDF accurately. Depending on your skill,

you can also cut multiple MDF pieces at once, guaranteeing they match in dimensions.

• Metal band saw: This is used for cutting the aluminum angled rail and lead screws.

• Hack saw: If a band saw is not available, this is the saw to use for cutting the aluminum angled

rail and lead screws.

• Mitre box: This is useful for making accurate cuts in small MDF pieces.

• Hammer: This is for hammering things, obviously.

• Cordless screwdrivers: You’ll need a Phillips and a slot head.

• Regular screwdrivers: Again, you’ll need a Phillips and a slot head.

• Forstner drill bits: Forstner bits are extremely useful for counterboring as well as

drilling large, smooth holes; regular drill bits can be used to drill counterbored holes, but these

work much better.

• Brad point drill bits: These drill a flat-bottomed hole and have a sharp, centered tip that creates

a“dimple” that can be used to center other drill bits for later drilling.

• Twisted drill bits: These are your standard drill bits and come in a range of sizes.

Spade drill bits: This is another common variety of drill bit that is perfectly acceptable for

drilling holes.

• Transfer punches: Transfer punches are available in different diameters. These

tools have a sharp point on the end; inserting them into existing drilled holes will allow you to

make a “dimple” in a second piece of MDF, giving you an accurate point to drill on the second

piece of MDF.

Magnetic bowl: This is a small bowl that can keep your nuts and bolts from falling all over the

floor.

• 1/2" power drill: Having a drill that can handle larger-diameter drill bits will be very useful

during the build.

• Drill press: Useful for drilling straight holes (vertically) through material. A drill press also

provides a small table to clamp MDF and aluminum rail to when drilling.


• Wrenches: You’ll need wrenches for 1/4" nuts.

• Detail metal ruler: This is a special type of ruler with marks that allow you to

make extremely straight lines for cutting and points for drilling. Measuring and marking

increments of 1/8", 1/16", 1/32", and 1/64" are possible with these rulers.

Center punch: This little tool allows you to make a small indentation in wood and metal to mark

where to drill.

• C clamps: Clamps will come in very useful for holding parts together as you cut or drill them.

• Bar clamps (of assorted sizes): These larger clamps will come in handy later when your CNC

machine begins to get bigger and you need clamps that can stretch wider and longer.

• Router: This is required for building your CNC machine. You’ll need to purchase a laminate

router (also called a hand router) to use with the chamfer bit.


DIFFERENT PARTS OF THE CNC

1. ANGLED CARBON STEEL RAIL


2. Various parts of CNC


Drilling and Mounting the Rail

Mark both pieces of 4' rail 3/4" from the ends. Drill 1/4" holes into the rails from the inside out,

not the outside in. (We found that drilling the holes using a slightly larger bit—5/16" is a good

size—it allows for a little wiggle room for the inserted bolts to find the holes on the sides of the

tabletop.)


Attaching the Table Legs

Use nails for attaching each leg. Some nails will be used on the top and some are used on the

bottom. Following figure shows nails connecting one leg to the table on top visible.


Cutting the X-Axis Lead Screw When your machine is done, it will use three different lengths of threaded rod to assist with the

movement of the router—these are called lead screws. One piece of lead screw will be used for

each axis, so you’ll want to go ahead and purchase enough threaded rod to cut all three pieces. If

you can find a hardware store willing to cut them to the lengths required, consider yourself

lucky; usually you’ll need to purchase them in precut lengths and then cut them to your desired

length.

Summary of Work

At this point, you should have the following items completed:

Rails attached to sides of tabletop

Parts T and U drilled with proper holes

Parts T and U mounted to the table


Y AXIS

Part R cut to the proper dimensions of 17 3/4"×7". Part Q is cut to the same

dimensions, and both pieces have been marked for drilling.

A Centre Punch is shown in the figure at the end of the page. You can create a small dimple in

the MDF to help you center the drill bit with more precision.


Next, clamp parts Q and R together, as shown in the following figure. You can drill the two parts

separately, but clamping them together saves time and can help to ensure that when the two parts

are mounted, their respective holes will match up.

Part Q Y-Axis Gantry Side

Part R Y-Axis Gantry Side

135


Preparing for the Z-Axis

The dimensions of the 2 Parts are fixed; cut these pieces to 4"×6 7/8" (6 and 7/8 inches).

You’re also going to need two BRAs(bottom rail assembly) after cutting and drilling Parts C and

D. So, go ahead and cut two pieces of angled aluminum rail to a length of 4" each. Use your

BRA template to drill pilot holes and then tap both pieces to make two BRAs. Set these aside

until you’re done drilling Parts C and D.

Summary of Work

At this point, you should have the following items completed:

Part C and D cut and drilled

Two BRAs assembled using a 4" rail length

One BRA bolted to Part C and one bolted to Part D

Parts C and D clamped to the y-axis frame rail for measuring

Height/length of Parts A, B, and F measured


DRILLING AND CUTTING MDF AND RAIL


Stepper motor


ASSEMBLY


Z-axis bearing support


Bed and XY assembly


Z-axis assembly


Angle with bearing


Top and Bottom bed assembly


XY-assembly


CHAPTER 3

DESIGN

3 Axis CNC Machine - MDF Plans and Cut List


Overall Dimensions and General Notes: 3'-6 7

16"

These measurements include only the MDF components and not other external components such

as motors, bearings, lead screws, etc.

.

Notes: All screw diameters and types will be 14" - 20 unless specified otherwise. Hole dimeters

and dimensions are seldomly repeated for simplicity. If there is an inquiry to a hole size, or a

position, refer to another part of the drawing.


Z AXIS BEARING SUPPORT

There are two of these pieces

on the machine. They serve as

supports for the linear bearings

and for the router mount.

Each piece is an exact mirror of

the other.

Hardware Needed:

4 2" screws to connect to the z-back support and the router

mount base.

434" screws to secure the linear

bearing angle.


Router Base This piece will be used dually as the router base and as a dust collector top.

There is only one of these pieces on the machine.

The diameter for the large hole for the vacuum hose should be modified to fit your vacuum hose.

The medium hole is used for the router collet to protrude. Router mounting holes will need to be

marked and bored so that your router can be utilized. The underside of this base should have

these holes countersunk so as not to reveal the screw heads as this may interfere with the

material to be cut. The four remaining holes is to receive a cross dowels to connect to the screws

from the Z Axis Bearing Supports.


Z Axis Rail Support

This piece will be used as the support for the aluminum angles as rails. The sides are chamfered

at 45 degree angles with a small portion of the MDF remaining for the router bearing quide.

The 4 holes at 7 16" are used to receive cross dowels to connect to the y-axis bearing supports.


Motor Mount These pieces will enable you to mount the motors to drive the linear motion.

Countersunk holes will need to receive the #10 nuts.

The two outside holes are to receive 3" screws in order to connect through the the main 3 4"

piece being attached, and two motor mounts.

The large center hole is simply to allow space for the couplings and if the bearing is not flush

against the main piece. There are six of these pieces on the machine.


Y Axis Linear Bearing Supports There are two of these pieces in the machine and they serve as linear bearing supports and to connect to the Z rail support and the Z back supports. You will need four 3 4" screws to attach the bearing angle (the four holes in the middle. Four 2" screws are needed for the four outside holes to connect to the y-axis back support and the z-axis rail support pieces. The two holes outside of the larger bearing hole is used to fasten the motor mount using 3"screws


Z Axis Back

Supports

The piece shown at the top is the z-axis back support piece that will also serve to hold the z-nut.

The piece at the bottom serves simpley as extra support for the router sides. Both will have a

center bore on each end to mount to the router sides (shown upper right).

For the piece shown at the top, two 1-1/2" screws and nuts are required to fasten the transmission

nut..


Y Axis Back Supports These two pieces are similar to the z-axis back support found on the previous page. These pieces will serve as the back support for the y-axis and one (top) will hold the y-nut. You will need four cross dowels, two for each. For the piece show at the top, two 1-1/2" screws and nuts are required to fasten the transmission nut.


Z Axis Back

Supports

The piece shown at the top is the z-axis back support piece that will also serve to hold the z-nut.

The piece at the bottom serves simpley as extra support for the router sides. Both will have a

center bore on each end to mount to the router sides (shown upper right).You will need four

cross dowels, two for each piece.

For the piece shown at the top, two 1-1/2" screws and nuts are required to fasten the transmission

nut.


Gantry Side

The Gantry sides serve to hold up the y and z axes and ride on the x-axis rails.

The five holes lined up on the left will connect to the y-axis rail support piece using 2" screws.

The six holes in a grid configuration are used to attach the bearing angle using 3 4" screws. The

three holes to the far right will connect to the gantry bottom piece and will require three 2"

screws.

The large holes is for the bearing and needs to be countersunk to the bearing thickness. The two

adjacent holes will hold the motor mount and will require the use of 3" screws.

There are two of the gantry sides in the machine each mirroring the other.


X Table End

There are two of these table ends on the machine, each an exact mirror of the other.

You will need six 2" screws to fasten this to the two table halves.

The two holes on either side of the bearing seat require 3" screws to fasten the motor mounts.


Y Axis Rail Support Front Reinforcement/

Y Axis Rail Support Front

This is the back part of the y-axis rail support piece. These will fasten with the 1" screws.

The main gantry support and the piece that supports the rails for the y-axis travel.

You will need 7 cross dowels on each side, two of which will be used to fasten the rail to the

piece. The other will be used to attach the gantry sides.

The 10 holes in the center will be used to fasten the reinforcement with 38 " countersinking (half

way through the 3 4" board) to allow 1" screws to be used. There should be very little protrusion

of the screw head or the nut so the z-axis assembly will not have obstruction.


Gantry Bottom Support

This is the piece that will serve as the support to maintain alignment and strength for the gantry

around the table rails.

Six cross dowels will be used to connect to the gantry sides and two 3" screws are needed to

fasten the x-nut piece.


Bottom Half of Table This is the bottom half of the complete table assembly. The piece is chamfered to receive two 1-

1/4" angles for linear motion of the gantry. The six holes in the middle are to be used to fasten

the two halves of the table together.

The five holes on either end will receive cross dowels. Three for connecting to the table ends and

two for holding the angles in place.

The two holes for the angle attachment should be drilled only after the two halves are prepared

and fastened together. 4'1" for the table length may seem non-typical; however, this is the

nominal dimension of stock found at the local home improvement store.


Top Half of Table The top half of the table will serve as the cutting surface. The holes in the middle are

countersunk so there is not protrusion of screw heads to interfere with the material to be cut.

Six 1-1/2" screws are needed for the middle holes to fasten the other table half.


CALCULATIONS

2 MDF Board

Dimension-

Length- 8 foot

Width-4 foot

Height-3/4 inch

RAIL (1)-

Thickness-1/8 inch

Width-5/4 inch

Length-8 foot

Cut this into two pieces of length 4 foot each.

RAIL (2)-

Thickness-1/8 inch

Width-3/4 inch

Length-9 foot

Cut into-

4 pieces of length-4 inch



2 pieces of length- 7 inch

Nut-24Nos.

Dia-5/16 inch

Length-1 inch

Bolt-24 Nos.

Bearing-24 Nos.

Inner dia-5/16 inch

Outer dia-3/4 inch


PARTS AND THEIR DIMENSIONS

1. Y AXIS BACK SUPPORT

Number of Pieces-2

Length- 10 1/16”

Width- 10 1/16”

Part letter- A and B

2. Z AXIS RAIL

Number of Pieces-1

Length- 10 1/16”

Width- 4”

Part letter- F

3. X TABLE END FEET

Number of Pieces-2

Length- 16”

Width- 6 25/32”

Part letter- T and U

4. GANTRY SIDE

Number of Pieces-2

Length- 17 3/4”

Width- 7”

Part letter- Q and R

5. GANTRY BOTTOM SUPPORT

Number of Pieces-1

Length- 2”

Width- 4”

Part letter- E

6. Y AXIS RAIL SUPPORT FRONT REINFORCEMENT

Number of Pieces-1

Length- 23 11/16”

Width- 6”

Part letter- S


7. GANTRY BOTTOM

Number of Pieces-1

Length- 26 11/16”

Width- 7”

Part letter- P

8. Y AXIS BACK SUPPORT

Number of Pieces-1

Length- 26 11/16”

Width- 8”

Part letter- 0

9. MOTOR MOUNTS

Number of Pieces-6

Length- 3 7/16”

Width- 2 1/2”

Part letter- G, H, I, J, K, L

10. TABLE

Number of Pieces-2`

Length- 49”

Width- 24”

Part letter- NONE

11. Z AXIS BACK SUPPORT

Number of Pieces-2

Length- 6 1/16”

Width- 1 1/2”

Part letter- M, N

12. ROUTER BASE

Number of Pieces-1

Length- 6 1/16”

Width- 8”

Part letter- V


13. Y AXIS LINEAR BEARING SUPPORTS

Number of Pieces-2

Length- 6 7/8”

Width- 4”

Part letter- C, D

14. Z AXIS BEARING SUPPORT

Number of Pieces-2

Length- 813/32”

Width- 7”

Part letter- W, X


Summary

As an undergraduate of PEC University of Technology, we would like to say that this

capstone project is an excellent opportunity for us to get to the practical experience and the things

that we would have never gained through going straight into a job. It is easy to work with

sophisticated machines, but not with people. The only chance that an undergraduate has to have

this experience is the capstone project period. We feel that we got the maximum out of that

experience. Also we learnt the way of work in an organization, the importance of being punctual,

the importance of maximum commitment, and the importance of team spirit.

In technical terms, we got to learn different manufacturing processes practically and why

that particular type of process is used at that particular place.


FUTURE SCOPE

The machine that we have retrofitted is just an example of preliminary retrofitting keeping in

mind the use and the costs incurred. There is a huge scope for further improvements in the

machine. These can be listed as below:

•A multi station tool turret can be incorporated in the existing CNC machine.

•Automatic Clamping mechanism can be installed (Draw bar Mechanism).

•Automatic Tool Changing (ATC) devices using Robotic Arm Technology.

•Automatic Pallet Changer (APC) for automatic work piece changing.

•A Chip Conveyor can be incorporated for easy and hassle free disposal of chips


REFERENCES

http://www.mydiycnc.com/

http://www.buildyourcnc.com/

www.kelinginc.net.

http://www.acksupply.com/

http://www.machsupport.com/

http://en.wikipedia.org/

http://www.mcmaster.com/

www.kellyware.com

www.linuxcnc.org

www.dakeng.com

www.mycnc.com

http://www.mydiycnc.com/

http://www.buildyourcnc.com/

http://www.kelinginc.net/

http://www.acksupply.com/

http://www.machsupport.com/

http://en.wikipedia.org/

http://www.mcmaster.com/

http://www.kellyware.com/

http://www.linuxcnc.org/

http://www.dakeng.com/

3 axis cnc

Documents