PROJETO-MÁQUINA CNC EM PEAD

BigBear CNC 2007 Mini-Mill Plan Set Thank you for purchasing the 2007 CNC mill plan set. This mill is the third generation design constructed with the best design characteristics of my previous designs. You should be able to build this mill with simple shop equipment. You will need the following: Table saw Drill Press Hand drill ¼-20 tap 10-24 tap Drill bits 13/64” and 5/32” (for ¼-20 and 10-24 taps) ½” drill bit 33/64” ream Read through the plans before you build. Get a good understanding of the job you are about to undertake before you begin. Here is the parts list for all the material you will need.

Part QTYPart Number Vendor

Unit Price Price (est.)

HPDE 2'x4'x3/4" Plastic 2 46039 usplastics.com $81.11 $162.22

Xylotex Kit 1

Top of Form

XS-3525/8S-3

Bottom of Form xylotex.com $345.00 $345.001/2" round Precision ground rod 24" 5 R212-TGP metalsdepot.com $5.20 $26.001/4-20 threaded rod 24" 2 TRCX-1420 smallparts.com $3.85 $7.701/4-20 threaded rod 12" 1 TRCX-1420 smallparts.com $2.30 $2.301/4" motor coupling 3 2424K11 mcmaster.com $5.91 $17.73Rotary Tool 1 none see below $100.00 $100.00Software BigBear CNC 1 www.bigbearcnc.com

Mach 2-3 1 www.artofcnc.ca $ 159.00

K-CAM 1 www.kellyware.com $ 95.00

Rotary Tool Options

Bosch router 1

Top of Form

PR20EVSK Bottom of Form www.amazon.com $89.95 $89.95

Top of Form

Porter-Cable 7310 Bottom of Form 1

Top of Form

7310 Bottom of Form www.amazon.com $99.99 $99.99

Top of Form

DEWALT DW670 Bottom of Form 1 DW670 www.amazon.com $106.04 $106.04

Tools You will need to build this machine. 1/4-20 Tap 1 none Local hardware $2.00 $2.00

10-24 Tap 1 none local hardware $2.00 $2.00#25 Drill Bit 1 none local hardware $2.00 $2.00#7 Drill But 1 none local hardware $2.00 $2.001.5" Forstner bit 1 G1269 www.Grizzly.com $9.95 $9.951/4" Drill Bit 1 none Local hardware $2.00 $2.00

Machine tools you will need to build this machine. Table saw Drill Press

Hand tools you may need Wrenches Screw Drivers Wire Cutter Volt Meter Wire Stripper Hex Head (Allen) Wrenches

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APPROVED

Michael Walach 4/7/2007

DWG NO

y-axis-table-new

TITLE

Y axis Table

SIZE

CSCALE

BigBearCNC

REV

n0.25 n0.25

3.3125

4.6875

1.375

0.50

6.3125 6.3125

10.50

22.00

0.75

0.375 0.38 0.38

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B B

C C

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y-axis-table-with-bearings

TITLE

Y axis table with Bearings

SIZE

CSCALE

BigBear CNC

REV

22.00

10.50

1.75

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y-axis-table-with-bearings-rails

TITLE

Y axis Table with Rails

SIZE

CSCALE

BigBear CNC

REV

24.00

22.00

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Y-axis-frame

TITLE

Y axis Frame

SIZE

CSCALE

BigBear CNC

REV

4.00

24.00

25.50 24.00

4.00

0.38

12.00

1.85

1.85

2.00

n1.50n0.25 n0.25

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Y-axis-non-motor-end

TITLE

Y axis non-motor end

SIZE

CSCALE

BigBear CNC

REV

24.00

2.00

12.00

1.00

3.00

0.375

0.375

0.75

n0.375 n0.25n0.25

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Y-axis-motor-end

TITLE

Y axis Motor End

SIZE

CSCALE

BigBear CNC

REV

0.75

12.00

11.08

5.625

4.375

2.00

1.85

1.00

3.00

1.25 1.25

0.375

n1.50

1.85

1.85

1.00

3.00

4.375

0.375

0.375

2.00

Begin Construction Y axis frame

You can start building whatever parts you feel most comfortable with first. When I built my machines I started on the Y axis frame, then built from there. So, I will begin with the Y axis instructions first. Following the Y axis prints, cut out the Y axis motor and non-motor ends from ¾” HDPE plastic. Once you have the parts cut, use double sided carpet tape to hold the motor end and non-motor end together. This will allow you to make sure both parts are identical and that all the holes you drill will line up end to end. Once the parts are taped together, cover one side with masking tape or blue painters tape. This will give you a good surface to layout all of your holes on. Use a pencil, ruler and straight edge to mark off all of the holes you will need to drill. I use a small nail or screw and hammer to make small indents where my holes will go. This helps keep the drill bit from “walking” too much when you drill. Drill all of the holes except the motor mount holes as these only need to be on the motor side of the y axis. Separate the two Y axis plates, and then drill the holes for the motor. I drill my motor holes in the following order.

1. Drill the large 1.5” hole first. 2. Set the motor into the hole and line it up with a straight edge. 3. Mark one of the 4 motor mount holes and drill it out. 4. Drop a screw into the hole you just drilled to hole it in place. 5. Mark you next hole and drill. 6. Drop a screw into that last hole and repeat for the next two holes.

The above procedure should assure that all of your holes line up. The next step is optional, but it will assure a square frame. Cut out a 24” x 24” piece of ¾” plywood, MDF or HDPE plastic. Build you Y axis frame around it. The square will help keep your frame square. I used ¾” plywood and left it in my machine. I screwed the y axis sided right into it with drywall screws. It helps keep my machine very rugged. I used plywood for this one part because it was cheaper than HDPE. Once your y axis frame is assembled with 10-24 screws, check for square, then move onto the X axis.

X Axis

Build the X axis in the same manner as the Y axis. Cut the X axis sides, then tape together with double sided tape. Layout and drill holes in same manner as the Y axis. It is important that the X axis be straight and true. One modification I may make here, is to use ¾” or even 1” rails on the X axis to better hold the weight of the Z axis. My machine runs great, but I think over time this axis may sag. So far, I haven’t had any major issues with this design. Many people say an unsupported axis is no good. However If you look at many industrial CNC machines you will see that they also use unsupported axis, and they work just fine. Here are some pictures of my X and Y axis going together.

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X-axis-side-motor-end

TITLE

X axis Side support

SIZE

CSCALE

BigBear CNC

REV

20.00

8.00 0.75

4.00

3.075

3.375

1.25

1.85

1.85

2.00

4.00

8.00

n1.50

n0.25

n0.25

4.92

0.75

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X-axis-side-non-motor-end

TITLE

X axis side support (Non-motor)

SIZE

CSCALE

BigBear CNC

REV

20.00

8.00

2.00

6.00

1.25

3.375

0.75

All holes are taped for 1/4-20 thread.

n0.25

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bearing

TITLE

Linear Bearings (Make 12)

SIZE

CSCALE

BigBear CNC

REV

2.00

1.00

1.2510

2.00

0.3745

1.00

0.50

n0.5020

n0.1945 n0.1945

0.3745 0.3745

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leadnut

TITLE

Lead Nut (Make 3) 1/4-20 Tap for Lead Screw (10-24 Tap for mounting holes)

SIZE

CSCALE

BigBear CNC

REV

2.00

1.00

1.00

0.3745

1.2510

n0.2010

n0.1495 n0.1945

0.75

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linear-rail

TITLE

24" linear Rail

SIZE

CSCALE

BigBear CNC

REV

24.00

n0.50

1/2" Prescion Ground Steel Rod (may use stainless in placeof plain steel as steel will rust without protection.)www.metalsdepot.com Part Number:R212-TGP 1/2 inch Dia. C1045 Cold Drawn Round - Precision Shafting

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rail-support

TITLE

Linear Rail Support Block

SIZE

CSCALE

BigBear CNC

REV

2.00

1.00

0.38

1.00

n0.25 n0.50 n0.25

0.75

0.50

1.25

Z Axis

Assemble of the Z axis will be you last major mechanical hurdle. There are a lot of parts that need to go together here. Don’t be surprised if you assemble and take apart the Z axis many times before you get it right. I spent a lot of time putting this axis together on my machine. Cut and drill the Z axis as well as the Z/X axis plates in the same manner as the X and Y axis. Here are a few pics of my Z axis going together. You can also see the X and Y axis in the back ground. (Notice the blueprints on the wall. This design went through many revisions before I was happy with it).

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z-axis

TITLE

Z axis assembly

SIZE

CSCALE

BigBear CNC

REV

13.50

8.00

4.75

2.00

2.00

1.25 0.38

2.00

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z-axis-motor-end

TITLE

Z axis motor end

SIZE

CSCALE

BigBear CNC

REV

4.00

8.00

1.00 3.00 3.00

0.375 1.25 1.450 0.925 0.925 1.450 1.25

n0.25

n0.25

n1.50

0.75

2.00

1.85

1.85

1.08

0.93

2.00

0.375

1.25

2.375

4.75

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z-axis-non-motor-end

TITLE

Z axis non-motor end

SIZE

CSCALE

BigBear CNC

REV

4.00

8.00

1.00 3.00 3.00

0.375 1.25 4.75 1.25

0.75

2.00

0.375

0.375

1.63 1.25

2.00

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zaxisplate

TITLE

ZX axis plate

SIZE

CSCALE

BigBearCNC

REV

0.50

1.62550

0.3745

4.00

6.3745

7.6255

4.00

6.00

7.50

0.50

0.50

4.00

7.50

8.00

8.00

3.50 3.50

2.3745

2.37

1.25

1.252.00

3.63

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z-axis-tool-plate

TITLE

Z axis tool-plate

SIZE

CSCALE

BigBear CNC

REV

1.00 3.00 3.00

0.75

0.375

8.00

13.50

n0.25

n0.375

0.38

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zaxis-with-bearings

TITLE

X-Z-plate with bearings

SIZE

CSCALE

BigBear CNC

REV

8.00

8.00

1.75

2.00

0.50

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z-x-axis-plate

TITLE

Z and X axis plate (Make 2)

SIZE

CSCALE

BigBear CNC

REV

0.50

4.00

7.50

0.3745

1.6255

0.3745

1.6255

4.00

2.00

3.37453.3745

n0.25

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n0.25

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full-mill-assembled

TITLE

Full Mill Assembled

SIZE

DSCALE

BigBear CNC

REV

25.50

20.00

8.13

4.00

25.50

17.50

24.63

28.50

28.50

More Pics!

Here are some pictures of my mill in different stages of construction. I use my mill in my classroom so I enclosed it in a wooded box and used foam for sound proofing. I also made a simple vacuum hold down table.

See direction and pics below on how to make one for yourself.

Vacuum hold down table is simple a small hole in a ¾” piece of HDPE plastic. Make a perimeter of vinyl tape used to seal windows, I found it at home depot in

the window seal section). Use a shop Vac or some vacuum source to draw suction. This simple design will you’re your work in place while you cut

it.

The adapter piece you see is used to accommodate smaller work pieces. I made several of these to hold different parts down. They work great. Use the vinyl tape on

the top and bottom of these adapters.

MW’s Mini Mill CNC router Drawn by: Michael WalachUpdated 3-18-2004

These plans are the copyright of Michael Walach Any Reproduction of any kind is a violation of copyright and is strictly forbidden!http://members.cox.net/

walachcnc

*****Disclaimer***** CNC machines can start and stop automatically. Electricity and power tools can be dangerous and or lethal if used incorrectly. Safety precautions should be used

at all times! Wear eye, ear and respiratory protection! These plans are only a reference for those who may be interested in one person’s approach at building a simple, cheap CNC machine. I am not an engineer or CNC expert. I have built this machine as a hobby machine to learn the fundamentals of stepper motors,

CNC and programming. I am willing to give advice and share lessons that I have learned throughout my building and design. However, I take no responsibility for any injuries or other mishaps that may result from the construction of this machine or any machine constructed with help from me or these plans. If you

are unsure of what you are doing, DON’T DO IT!!!! Modifying, tampering with or altering in anyway electronic devises, motors, circuit boards etc, may result in fire, shock injury or death. In short, I take no responsibility for anything you do,

BE CAREFUL and use caution!!!!

Thank you for purchasing these plans for the MW Mini-Mill. These plans provide you with the means for building an inexpensive yet accurate CNC milling machine. I built my Machine for around

$500, including motors, driver board and power supply. Can you build this machine for the same price or less? It depends on your level of skill and how well you can scrounge. Most of my supplies I purchased through mail order via the web. My biggest expenses were my motors and driver board. I was able to get decent motors from Ebay for about $20 each. I used a Xylotex driver board ($130.00 www.xylotex.com) for my stepper motor driver. It was very easy to set up, and support from Xylotex is great. You may choose to make your own drivers, or build your own supply. I modified 2 computer power supplies for my machine’s power, although this takes some electronics knowledge. The more

you build yourself, the cheaper the machine (In theory anyway). Inside this booklet of plans you will find blueprints, parts lists, suppliers list and assembly notes. Read through the plans carefully

before you start to build. I would recommend that you order your materials, and read through this packet while you wait for you materials to arrive. I hope there are no mistakes in these plans, however if you find any inaccuracies let me know so that I can keep my plans accurate and up to

date. Feel free to email me any questions regarding construction, set up or parts. [email protected]

The Mini Mill complete

They say a picture is worth a thousand words

Drill through holes for mounting hardw are (10-24 or similar)Overdrill slightly to leave room for adjustment later.

1"

2 1/2"

1/2"

1 1/4"5/8"

Ø 1/2"

Guide rail support Blocks

Guide rail support Blocks

These guide rail support blocks are a new modification from my old machine. They allow for adjustment to the guide rails to assure proper alignment of the system. They are made from Plastic. I used 3/4” pieces, preferably scrap from my other larger pieces. You will need to make 12 of these, 4 for each of the three axes. It is very important that these be made all at once. You should also label each one as you make them. Mark the top bottom, right side left side etc, so you know which way to position them on the machine. The reason for this is that as you drill them, they will likely be off a little to one side or the other. By drilling each the same way and marking them, the error will be in the same place on each one. Follow these simple steps below to insure some accuracy.

1. Cut out all 12 blocks and make sure the are all the same size. If you have one that is not right fix it or throw it away!2. Build a fixture to hold the blocks as you drill them. A simple “L” shaped fixture should do the trick. Make sure the fixture is secure and will not move. I used a clamp and clamped it to my drill press table.3. Mark each piece with marker or something that will not easily wipe off.4. Check each piece with all the others and make sure they are the same. If you mess one up, throw it away! I made a few bad one when I built mine. Don’t try to save ten cents worth of plastic on a bad part!5. Make sure your hole pattern lines up with those on your end plates that you will build. 6. The large hole needs to be a tight fit for your guide rail. If you have 1/2” guide rail, a 1/2” might do it. You can use a rubber mallet to press it in. If need be, buy a 31/64” or 15/32” drill bit or ream. ****TIP*** I made an extra support block and used it as a template to drill the mounting holes in my Y, X and Z end plates. This assures your holes will line up!

These are my latest modifications for the original mini mill. I have made this new machine sturdier and more accurate than my first machine. I have switched from MDF (medium density Fiberboard to high density plastic. Plastic is worked just as easy as wood, with much more stable results. If you plan to modify this machine, I can not guarantee your results. Adding weight and or length increases the odds of bind up and inaccuracy. I can offer my best advice, but in the end the design changes are your own decision.

As for the construction of this machine, You should follow the steps below in the order that I suggest. The order of assembly does make a difference. If the machine is out of alignment it will bind up. A mis-aligned machine could result in motor or controller failure. Read the instruction to the controller board very carefully!

Assembly. You will build the Y axis first.

1. Cut out the two Y end supports. 2. Tape the two end plates together with duct tape before drilling holes. This will assure holes are in same location on both pieces. Also mark top and side of each piece. This will be important when as-sembling later. 3. Drill holes as indicated below. Tap holes as determined to fit your mounting hardware.

Y axis-support end

Y axis-drive end

Linear Bearing

Linear BearingLinear Bearing

Linear Bearing

Steel Guide Rail Steel Guide Rail

Shaft coupling

Nylon Bushing

10-24 bolts

10-24 nutFlat washerLock washer

Y Axis assembly PrintCopyright: Michael Walach 2004 **Note** Parts not drawn to scale

Guide supports

1/4-20 lead screw

10-24 boltFlat washerLock washer

Here is a look at the assembly of the Y-axis. As you can see you need your Linear bearings so we will make them next, then assemble the Y axis.

3"

1/2"

Ø 33/64"

1"

Y axis Linear BearingMake 4

Copyright 2004: Michael Walach

Drill and tap for 10-24 bolt

1/4" 1/4"

1"

Linear Bearings

Use 1” Delrin plastic to make bearings. Drill through holes so that guide rail slides smooth, but not too loose. There should be no “slop” in the bearings. A drill press is recommended for this process.

Before you assemble the y axis you need to construct a parts table. Cut a piece of high density plastic to the size shown below.

The parts table will move on the Y axis. It must be able to clear the X axis supports so its width is limited to about 22” max. The distance that you space the linear bearings will determine 2 things: Travel on the Y axis and stability of the table. The closer together the bearings, the more travel, but the least stability. I would recommend spaceing them about 2 inches in from the end of the table. My table is about 20” x 12”.

Stepper motor

Precision Ground Steel Rod

1/4-20 threaded rod

Attach w ith 10-24 boltsDrill counter sinks so that screw heads

are below the surface of table.

Support BlocksSupport Blocks

**Note** Guide rails should pressinto support blocks tight, thenbe locked in place w ith a setscrew .

Assembly notes:1. Slide linear bearings onto guide rails.2. Attach guide rails into support blocks.3. Attach support blocks to end supports.4. Make marks on parts table to locate through holes for linear bearings and lead nut. (see figure for lead nut construction).5. Attach linear bearings and lead nut to parts table to assure holes align.

***Note*** Chances are that table will be bound up and not slide at this point. That is ok. A few .001’s of an inch off will cause this. This next section will explain the alignment process which you will

use for the other two axes as well.

Alignment Procedure1. Disassemble the Y axis.2. Slide linear bearings onto guide rails.3. Attach ONE set of linear bearings to the parts table. (see figure below.)4. Attach bearings loose so that rail can slide through bearings smooth.5. Slowly tighten screws until snug, adjusting bearings as you go to keep rail sliding smooth. **Note** every time you tighten a screw you twist the linear bearing binding the slide. It takes a little patience to get this right, but this rail must slide smooth for proper operation of this machine! Take your time!

Support Blocks

Linear bearings under table. Attach loose.

6. Once one side is tightly secured and sliding free, attach the other rail in the same manner. Make sure both are sliding smooth. **note** If you over drill the through holes in your parts table by a few thousandths, it gives you a little room for adjustment at this alinement stage.7. You should now have the figure pictured below. Each rails should slide smooth. As you work them back and forth they should get easier to slide.


Finish Y axis assembly1. Attach the guide rail support blocks to the Y axis end plates. Attach the screws loose at first then slowly tighten.

2. The through holes in the support blocks should also be slightly over drilled to allow for some play in the end for alinement. Once your table slides free, you are done with alinement.

3. Thread your Lead screw (1/4-20 threaded rod) through your lead nut (delrin block tapped for 1/4-20).

4. secure the lead nut to the parts table. You should be able to turn the lead screw by hand and move the table.

5. you can now attach you drive motor to the Y axis end plate and secure the motor coupling to the lead screw.

**Note** If you need a moral booster, you can power up this motor and watch the table move. Be careful not to blow up your control board or motor. Things at this stage are usually a little messy (ie. loose wires, parts lying around the shop).

6. If you want limit switches to power down the axis when it hit its limit this would be a good time to install them.

Y Axis Assembled

Stepper motor

Precision Ground Steel Rod

1/4-20 threaded rod

Attach w ith 10-24 boltsDrill counter sinks so that screw heads

are below the surface of table.


Guide rails should pressinto support blocks tight, thenbe locked in place w ith a setscrew .

Mounting the Y axis to the base with side supports.

You will now mount the Y axis to the machine base. The machine Base is also made from plastic. It only needs to be large enough to fit inside the y axis end plates. There fore it should be 24” wide by 22-1/2” long, however this may be different if you modified you machine at all. It is best to measure the distance between your Y axis end plates to deter-mine a tight fit. The side supports will be 4” high (the same height as the Y axis end Plates and 24” long. Drill and tap holes in the base to attach the end plates and side supports.

Base 22-1/2" x 24"

Side Support 24" x 4"Make 2

Side supports

Base

Y axis with base and side supports installed

X axis

X axis support plates

Linear BearingsGuide rails

Threaded rod

Stepper motor

The axis is assembled in much the same manner as the Y axis. The carriage that slides on the X axis is actually the Z axis. In order to align the X axis you will build the back plate of the Z axis. The X axis fits inside of the Y axis and is later bolted in place (you will do this later). Below is an overview of the X axis. Note the two vertical end plates (see print on previous page for size specs.) The verti-cal end plates are constructed in the same manner as the Y axis end plates were. You will tape the two end plates together and mark them before you drill your holes. As with the Y axis drill a small pilot hole in the center of the motor mount marking where the motor shaft will be. When you take the two end plates apart, this pilot hole will guide your 1/2” hole on the end plate opposite your mo-tor. On the end plate holding the motor, the pilot hole will act as a guide for the larger hole you will drill for your motor. All other holes you can drill with the end plates taped together. It is important that the holes for the guide rail support blocks be in the same location on both end plates to assure the guide rails are parallel.

X and Z axis Linear bearingsUse 1” Delrin Plastic Stock

Use above print for lead screws, except drill and tap a hole for 1/4-20 thread instead of

33/64” through hole.

The Z axis is built in much the same way as the other Axes. The Z axis will travel along the X axis, plus it will have its own carriage that will slide up and down. I will give you some suggestions for your tool mount, but you will need to adjust depending on your rotary tool. The guide rails for the Z axis will also be attached with end support blocks as the X and Y axis where. You can play around with the size of the Z axis to achieve the Z movement you will want. This is the smallest axis, but can take the most figuring to build. On my plastic machine I only have about 1-1/2 to 2” of Z travel. This is fine for me, but I do have instances where 3 to 5” might be better. You want to have enough clear-ance between the table and the bottom of the Z axis so that your thickest piece of stock can fit there.

As for the tool mount, I used a simple clamp on both of my machines. A dremel doesn’t have that much torque where it is going to rip the tool hold apart, but you want to minimize as much movement as possible. I used a simple two piece tool mount as shown in the color photo in this book. On my first machine however I used a nicer clamp as shown here (large print on next page).

Z axis and Tool Mount

5V Reg

24V Reg

in out

in out

24V 10 AmpTransformer120VAC to 26VAC

Full Wave Bridge Rectifier120VAC 20 Amp switch

Fuse

120VAC Power

Power Supply

Disclaimer: The drawing below is a sample for reference only. Building a power supply should only be done by someone with a solid working knowledge of the principles of electricity. It is far safer and maybe cheaper to purchase a power supply already assembled. The circuit shown below doesn’t have any safety features with the exception of the fuse. You should not attempt to construct this type of circuit if you have no prior electrical knowledge. Miss wiring can cause electrical shock which can result in serious injury, fire or even death. Line voltage is extremely dangerous even to those trained to work with it.

On my system I used modified computer power supplies. I have also found power supplies on-line at discount whole-saler for as little as $40. Ebay is always a good place to look as well as any of the electrical supplier I have listed at the end of this book. If you wish to construct you own use caution and common sense. Always assume a circuit is live!

Closing Remarks

I hope you have found the information here helpful. You have taken on a large task that you will find very rewarding in the end. You may find that this is only your first machine. I set out to build only one machine, but after the first I was determined to build it bigger and better. I did just that. I am sure you will have bumps in the road, a lot of frustra-tion, and things that just don’t work. My best advise is to walk away and come back another day. I often find when I get frustrated with a problem, looking at it longer will not yield an answer. As Albert Einstien Said “Insanity is do-ing what you have always done, and expecting different results”. You can always send me an e-mail if you get really stuck, and I will try to respond as promptly as I can. Everyone is building their machine for different reason and with different goals in the end. Feel free to modify this design, but I do not guarantee and thing. I have only tested this one limited design with a small rotary tool. Larger tools and larger machines create more problems. I wish you the best of luck and good luck building!

Take care,

Mike Walach

http://members.cox.com/walachcnc

Material Selection

Do not buy 1/4-20 rod from your local hardware store. It will not be very straight and it will cause you much grief. I ordered mine from www.smallparts.com. It came packaged very well, and was nice and straight with clean threads. Only about $3 -$4 a piece.

I found nylon spacers at both Home Depot and Ace hardware stores.

You can buy new motors very often on Ebay. If you know what you are looking for, and look often you can find some deals. Just be careful. I have had good luck with Ebay so far. I figure any deal that gives me motors for $20-$25 or less a piece is an ok deal. More than that is a lot, unless they are high torque motors. I looked up actual cost of motors first, then searched Ebay for the same motors.

Delrin can be found at US plastics Inc, or Ebay. 1”x 1” delrin is about $10 per foot.

Parts List(2) 24 x 48 x ¾ HDPE Plastic www.usplastics.com(5) ½ x 24 precision ground rod www.metalsdepot.com(1) 4’ x 1 x 1 Delrin plastic bar stock www.usplastic.com(2) ¼-20 x 24 threaded rod www.smallparts.com(1) 12 ¼-20 threaded rod www.smallparts.com(1) 2’ length of ¼ rubber tubing local hardware store(1) 1/4” motor coupling www.mcmastercarr.com(1) ¼-20 nuts local hardware store(1) ¼ Flat washers local hardware store(1) ¼ Lock washers local hardware store(1) 10-24 bolts local hardware store(1) 10-25 Nuts local hardware store

Dealer part numbers

Precision ground rod (Linear shafts)

www.metalsdepot.com P/N R212-TGP C1045 Cold Drawn Round - Precision Shafting 1/2 inch***Note*** this is probably not stainless steel and may rust. No rust on mine yet, but cutting wet wood? For the price I don’t mind.

Threaded rodwww.smallparts.comTRCX-1420-24 S/S THREADED ROD C/R 1/4-20 24” LONGTRCX-1420-12 S/S THREADED ROD C/R 1/4-20 12” LONGCold rolled stainless steel

Xylotex control boardwww.xylotex.comThe XS-3525/8S-3 Stepper Motor Driver BoardThree axis bipolar drive ±2.5 Amp/Phase PWM controlled drives up to 35 Volt (w/BEMF) FULL, HALF, QUARTER, & EIGHTH step/Full Step 5 Volt Logic ( < 50mA typ.) Synchronous Rectification Internal UVLO and Thermal Shutdown circuitry Easy connect for most popular Step/Direction control software Small Size: 4.275” X 2.84”

Other sources of supplies and infohttp://www.hobbycnc.com/ parts for hobby machineshttp://www.3drouters.com/photos.htm full systems for around $2000http://store.yahoo.com/cnclinx/index.html cheap CNC partshttp://www.aaroncake.net/electronics/vblpt.htm info on programming the Parallel porthttp://www.artofcnc.ca/ Master 5 Mach 1 Mach 2 available here

Upgrading your machineOk, so you want to upgrade your machine. Where do you go? Below is a list a manufactures of precision components. They are not cheap, but they make very nice parts for your next CNC machine.

Pacific Bearingwww.pacificbearing.com

Techno inc.www.techno-isel.com

W.M. Berg inc.http://www.wmberg.com/

Nook Industrieswww.nookindustries.com

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