3 axis cnc
TRANSCRIPT
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
3 Axis CNC PEC UNIVERSITY OF TECHNOLOGY
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.
Jeewanjot Singh (11109014)
Dated: Dec 2014 Manjeet Singh (11109018)
Pradeep Tiwari (11109020)
Rohit Jhanwar (11109023)
Sumer Singh (11109025)
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
3 Axis CNC PEC UNIVERSITY OF TECHNOLOGY
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.
Jeewanjot Singh (11109014)
Manjeet Singh (11109018)
Pradeep Tiwari (11109020)
Rohit Jhanwar (11109023)
Sumer Singh (11109025)
3 Axis CNC PEC UNIVERSITY OF TECHNOLOGY
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.
Jeewanjot Singh (11109014)
Manjeet Singh (11109018)
Pradeep Tiwari (11109020)
Rohit Jhanwar (11109023)
Sumer Singh (11109025)
3 Axis CNC PEC UNIVERSITY OF TECHNOLOGY
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.
3 Axis CNC PEC UNIVERSITY OF TECHNOLOGY
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.
3 Axis CNC PEC UNIVERSITY OF TECHNOLOGY
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
3 Axis CNC PEC UNIVERSITY OF TECHNOLOGY
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
3 Axis CNC PEC UNIVERSITY OF TECHNOLOGY
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
3 Axis CNC PEC UNIVERSITY OF TECHNOLOGY
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
3 Axis CNC PEC UNIVERSITY OF TECHNOLOGY
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.
3 Axis CNC PEC UNIVERSITY OF TECHNOLOGY
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.)
3 Axis CNC PEC UNIVERSITY OF TECHNOLOGY
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.
3 Axis CNC PEC UNIVERSITY OF TECHNOLOGY
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.
3 Axis CNC PEC UNIVERSITY OF TECHNOLOGY
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
3 Axis CNC PEC UNIVERSITY OF TECHNOLOGY
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.
3 Axis CNC PEC UNIVERSITY OF TECHNOLOGY
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.
3 Axis CNC PEC UNIVERSITY OF TECHNOLOGY
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.
3 Axis CNC PEC UNIVERSITY OF TECHNOLOGY
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.
3 Axis CNC PEC UNIVERSITY OF TECHNOLOGY
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
3 Axis CNC PEC UNIVERSITY OF TECHNOLOGY
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.
3 Axis CNC PEC UNIVERSITY OF TECHNOLOGY
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.
3 Axis CNC PEC UNIVERSITY OF TECHNOLOGY
CHAPTER 2
FABRICATION
ASSEMBLY (SIDE VIEW)
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ASSEMBLY (FRONT VIEW)
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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-23.68 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
3 Axis CNC PEC UNIVERSITY OF TECHNOLOGY
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.
3 Axis CNC PEC UNIVERSITY OF TECHNOLOGY
• 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.
3 Axis CNC PEC UNIVERSITY OF TECHNOLOGY
DIFFERENT PARTS OF THE CNC
1. ANGLED CARBON STEEL RAIL
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2. Various parts of CNC
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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.)
3 Axis CNC PEC UNIVERSITY OF TECHNOLOGY
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.
3 Axis CNC PEC UNIVERSITY OF TECHNOLOGY
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
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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.
3 Axis CNC PEC UNIVERSITY OF TECHNOLOGY
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
3 Axis CNC PEC UNIVERSITY OF TECHNOLOGY
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
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DRILLING AND CUTTING MDF AND RAIL
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Stepper motor
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ASSEMBLY
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Z-axis bearing support
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Bed and XY assembly
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Z-axis assembly
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Angle with bearing
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Top and Bottom bed assembly
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XY-assembly
3 Axis CNC PEC UNIVERSITY OF TECHNOLOGY
CHAPTER 3
DESIGN
3 Axis CNC Machine - MDF Plans and Cut List
3 Axis CNC PEC UNIVERSITY OF TECHNOLOGY
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.
3 Axis CNC PEC UNIVERSITY OF TECHNOLOGY
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.
3 Axis CNC PEC UNIVERSITY OF TECHNOLOGY
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.
3 Axis CNC PEC UNIVERSITY OF TECHNOLOGY
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.
3 Axis CNC PEC UNIVERSITY OF TECHNOLOGY
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.
3 Axis CNC PEC UNIVERSITY OF TECHNOLOGY
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
3 Axis CNC PEC UNIVERSITY OF TECHNOLOGY
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..
3 Axis CNC PEC UNIVERSITY OF TECHNOLOGY
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.
3 Axis CNC PEC UNIVERSITY OF TECHNOLOGY
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.
3 Axis CNC PEC UNIVERSITY OF TECHNOLOGY
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.
3 Axis CNC PEC UNIVERSITY OF TECHNOLOGY
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.
3 Axis CNC PEC UNIVERSITY OF TECHNOLOGY
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.
3 Axis CNC PEC UNIVERSITY OF TECHNOLOGY
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.
3 Axis CNC PEC UNIVERSITY OF TECHNOLOGY
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.
3 Axis CNC PEC UNIVERSITY OF TECHNOLOGY
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.
3 Axis CNC PEC UNIVERSITY OF TECHNOLOGY
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-10.06 inch
2 pieces of length-23.68 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
3 Axis CNC PEC UNIVERSITY OF TECHNOLOGY
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
3 Axis CNC PEC UNIVERSITY OF TECHNOLOGY
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
3 Axis CNC PEC UNIVERSITY OF TECHNOLOGY
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
3 Axis CNC PEC UNIVERSITY OF TECHNOLOGY
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.
3 Axis CNC PEC UNIVERSITY OF TECHNOLOGY
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
3 Axis CNC PEC UNIVERSITY OF TECHNOLOGY
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