Picture of $20 CNC Machine
I got inspired for this instructable when I viewed the Easy To Build Stepper Controller

instructable .When I read the instructable I knew I could make a decent looking and functioning cnc machine for under 20 dollars with a recycled twist, Not to mention I did this in under a week.

I expect you to have basic knowledge on power tools and hand tools
and of course this instructable requires you to have a rotary tool such as a dremel.
Even if you don't have knowledge on power tools or hand tools I advise you to try this instructable because you will learn a lot about hand and power tools and you can build this for less then 20 dollars
so if you mess up it's no biggie and it would not cost to much to replace a part.

Let's Build!

Update 02/01/10

{Hi everyone just thought I would give you an update on this instructable since Ive been getting
a lot of emails and messages and such.

I'm getting really close to completing the electronics for the CNC,
as stated in a comment the steppers I found in the printer were bi-polar stepper motors which the circuit
would cost quite a bit more if you went this route. If you were lucky to find some Unipolar stepper motors
then you could build the electronics for under 3 bucks however unipolar motors have less torque. I will be selling CNC kits soon and they will be of better build quality as well as a cheap price tag because I know how it is to be on a budget and not have the tools I need to create simple things and even complex things and this world needs more DIY builders.

The CNC kits will be available roughly 1 to 2 weeks after the electronics Instructable has been released
their will actually be a video showing this CNC working when the electronics Instructable is completed} 

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Step 1: Find recycled material

Picture of Find recycled material
Now this is the most enjoyable part of building the cnc machine
which is trying to find garbage that people want to throw away.

Here's what you need to locate

Flat bed scanner

Old printer

These two items are going to have your juicy stepper motors and the
beautiful harden steel rods, that's not the only thing you can get out of these green machines.

You will find gears, bushings, cold cathodes, capacitors, buttons, parallel ports and there is
so much more.

Step 2: Tools

Picture of Tools
Now I tried to build this with the bare necessities so I could show you that it is possible to
make a cnc machine with very little.

Required Tools:


Screw drivers

Tap and Die set

Rotary tool

Hack saw

Vise or some form of clamping device


Drill bits


Center punch

Recommended Tools:

Band saw

Table saw


Bench grinder

Bolt cutters

Step 3: Linear slides of fun

Picture of Linear slides of fun
The center core of your cnc machine is your tables
so read carefully and follow the instructable.

Required materials

Quantity Type Cost

4 2"x6"x1/2" Expanded PVC 2.00

2 2"x4"x1/2" Expanded PVC 1.00

2 10" 3/8" Aluminum rod 0.75

2 12" 3/8 Aluminum rod 0.75

2 8" 3/8" Aluminum rod 0.50

1 11 1/4" 5/8"-24 threaded rod 1.00

1 9 1/4" 5/8"-24 threaded rod 0.75

1 7 1/4" 5/8"-24 threaded rod 0.50

Now this is just the run down of everything
I of course cut everything up, you can purchase everything you see here from your local
hardware store and plastic store for really cheap.

First step

Stack 2 of the expanded pvc pieces that are the same size and drill a whole in the center
and two holes each three quarters of an inch from the edge from the center line.

Now cut your aluminum rods to size and stick them through,
now you should have a comparable piece down below

Repeat for all Axis

Step 4: X,Y,Z tables for your brunch

Picture of X,Y,Z tables for your brunch
Alright now here comes the most time consuming part
making the tables for the slides but once they are made it really feels like the project
is taking off.

Required Materials

Quantity Type Cost

1 6"x12"x1/4" Acrylic sheet Scrap

1 6"x10"1/4" Acrylic sheet Scrap

1 5 1/2"x5"x1/4" Acrylic sheet Scrap

15 1 1/2"x1 3/4"x1/2" Acrylic sheet Scrap

Now what you are going to want to do is stack 4 pieces of the 1 1/2"x1 3/4"x1/2"
and drill dead center with a 3/8 drill bit

After you have done so feed 2 pieces on each rod
and line them up and place your sheet on top and flip it over now glue.

Repeat for each axis

For your Y axis

now would be a good time to drill your holes so you can mount things you wish to cut.

Step 5: Motor mount time

Picture of Motor mount time
Now depending on where you get your motor from
they are all going to be different so they will require special mounts

I recommend printer stepper motors because they are easy to mount but scanner steppers motors will work just fine.

Now in step three you should have drilled the motor hole and now all you have to do is mount it in

The coupler that attaches from your stepper to your threaded rod is going to be different based on
stepper you have.

I made one out of aluminum but you can make one out of plastic just as long as it is wide enough.

All you have to do is drill in the center of a little piece of rod
to the size of the stepper then on the other side drill 5/16 for the threaded rod.
After that tap the 5/16 side
And glue

Step 6: Thread me please

Picture of Thread me please
Now once you have made your coupler it's time
to attach the threaded rod and glue a threaded coupler to one of the 1 1/2"x1 3/4"x1/2" square blocks

You have to make sure that the center on the threaded coupler matches the center of the threaded rod.

After you should get something like down below

Required Materials

Quantity Type Cost

3 5/8"-24x1" threaded coupler 0.60

Repeat for each axis

Step 7: Gluing time

Picture of Gluing time
So now you should have all three axis completed and now it's time to line them up and glue.

The base I used was a 20"x12"x1/4" piece of white acrylic I found at the plastic store

You could use smaller but I wouldn't recommend it

Once you have found a base, glue your x axis to it and then your y axis to your x axis acrylic top,
then you should have something like down below.

use acrylic glue
for this step

it will glue expanded pvc as well if your wondering

After that Glue your z axis to a piece of
8"x4"x1/4" acrylic sheet.

Required materials:

Quantity Type Cost

1 20"x12"x1/4" Acrylic sheet scrap

1 8"x4"x1/4" Acrylic sheet scrap

Step 8: Where's the Z axis :(

Picture of Where's the Z axis :(
Don't worry I didn't forget about that

Moving along

Now we want to add a mount for are rotary tool to the acrylic sheet on the z axis

I used a pipe holder and a screw clamp, you can buy both these items at a local hardware store for really cheap.

You have to cut a little lip to attach to the acrylic sheet because the pipe mount isn't going to be flat once you slide the rotary tool in because it expands.

Place the pipe mount on top of the acrylic lip and glue.

Required Materials

Quantity Type Cost

1 Pipe mount 0.40

1 Screw clamp Free

Step 9: A piece from the heaven's

Picture of A piece from the heaven's
Now that you made your z axis rotary mount it's time to set up
the posts and the acrylic sheet that connects them.

You need a square hole in the center of the 10"x16"x5/16" acrylic sheet to feed your z axis through

After you have cut that out it's time to attach a thick piece of a acrylic
to support the z axis on.

After you have done that you should attach you z axis to it and make sure the acrylic piece is sticking out at least 1/16" off the edge so you can have a flat side.

Required materials:

Quantity Type Cost

1 10"x16"x5/16" Acrylic Sheet Scrap

1 1 1/2"x5"x1" Acrylic Sheet Scrap
(aka thick piece)

Step 10: Tall posts oh my!

Picture of Tall posts oh my!
Now it's time to glue
the 1 1/2"x16"x1" posts to the z axis acrylic top
and then after your done with that, you then glue it to the base.

Required Materials:

Quantity Type Cost

4 1 1/2"x16"x1" Scrap

Step 11: Are we done yet!

Picture of Are we done yet!
The answer is no but we do happen to be mechanical done
now because of the short amount of time I had I could not add the electronics part to this instructable,
so I am going dedicate an entire instructable just to the electronics part some time this week as well as a video.

So turn that frown upside down

Word of advise this is quite a bit of work even though it may not look like it
so by the time you have this finished the electronics instructable will be beyond finished.

I will most likely add it on Tuesday or Wednesday of this week.

Part list:

Quantity Type Cost

4 2"x6"x1/2" Expanded PVC 2.00

2 2"x4"x1/2" Expanded PVC 1.00

2 10" 3/8" Aluminum rod 0.75

2 12" 3/8 Aluminum rod 0.75

2 8" 3/8" Aluminum rod 0.50

1 11 1/4" 5/8"-40 threaded rod 1.00

1 9 1/4" 5/8"-40 threaded rod 0.50

1 7 1/4" 5/8"-40 threaded rod 0.25

1 6"x12"x1/4" Acrylic sheet Scrap

1 6"x10"1/4" Acrylic sheet Scrap

1 5 1/2"x5"x1/4" Acrylic sheet Scrap

15 1 1/2"x1 3/4"x1/2" Acrylic sheet Scrap

3 5/8"-24x1" threaded coupler 0.60

1 20"x12"x1/4" Acrylic sheet scrap

1 8"x4"x1/4" Acrylic sheet scrap

1 Pipe mount 0.40

1 Screw clamp Free

4 1 1/2"x16"x1" Scrap

? Scrap from Tap Plastics 12.00

Total= 19.50

I got all my plastic from tap plastics scrap bin and I got the rest of the pieces from home depot
and a local metal supply shop.

Step 12: Recommendations

Picture of Recommendations
Now the stepper motors you find in a printer would do just fine
but after a while I would highly recommend to upgrade to some bigger stepper motors.

As for the expanded pvc I would replace that with Acrylic but do to the fact that I had a budget and the short amount of time I had no choice but to go with expanded pvc but I would really recommend you use acrylic.

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electronics soon to come?

volkvanmyn253 months ago
the mechanical parts of a cnc machine like this is the most difficult part. its easy building stepper motor drivers and a microprocessor controller. you can even find software on the internet driving it.
KyleM86 months ago

would a printer with a built in flat bed work?

Pramithus8 months ago


Thanks for posting such a wonderful project. But I am confused that how to wire the electronic components and computer to this machine. Could you please make it clear?



Cool. I might try this one.

can not

OK I have taken my share of scanners and printers apart, and I know that the stepper motor pictured in step 5 did not come from a printer or a scanner. Where did you get it?
Techbuilder (author)  Electronics Man3 years ago
I got it from an old epson printer sorry to disappoint you but it was from a printer
WOW thats a huge motor to come out of a printer! I need to find one of those...
Techbuilder (author)  Electronics Man3 years ago
1 1/2" x 1 1/2"is big to you?
Well apparently the images are misleading. Even if they are small, they are definately bigger than the ones I pulled out of my printers.
Techbuilder (author)  Electronics Man3 years ago
Never assume by a picture unless you have a reference point
like a ruler or a quarter so fourth.
You could also check the dimensions in step 3


Alright...but are those steppers strong enough to work properly? Could you provide the brand and the ratings for them please???
Techbuilder (author)  Electronics Man3 years ago
They were minimal at best probably enough to cut through some foam and light plastic. you can only get so much torque out of a little printer motor without sacrificing tremendous speed.

I no longer have the cnc machine anymore I sold it
so I can't really provide those specs
zack2474 years ago
i have 3 cd drive lens assemblies (EG: the lens shell holder, the rods, the stepper motor and the base)

could i use those to make this?


you just have to check if the stepper motors are uni polar or bipolar. both will work, but they require different circuit boards. other than that I'd be worried if they are strong enough, but hey, worst you can do is try and they break

so good

Moab1 year ago

Good idea trying with this material. I think it would work best for small machines as it is flexible.
With this in mind, the drill stand frame is poor design. First its poles are way too high. The link between the drill stand and the frame of the machine should be as short, strong and direct as possible.
The other axis seem to be less fragile but could be improved.
Gluing : Not good for precision and stops you from dissassembling if you need to transport or repair the machine.
Lastly, nothing is said on how things are aligned perpendicular and parallel.

naught1011 year ago
$20 for anyone who has hundreds of dollars worth of scrap perspex lying around...

I don't know where you are buying your acrylic from but I have loads, about 6 kilos in weight and its cost me little over £10!......... ebay, just look for off cuts

haha! I thought the same. One man's trash is another man's $300 project. Still a nice simple build.


dmhoke1 year ago

is this a dead project. I see no link to the electronic portion, and the author said he was going to post those 4 years ago.

What gives???

nice and green!
where is ghe electronics instructable?
hotcheezy2 years ago
When is the electronics part ever going to come out?
my wookie2 years ago
nice anvil in the background there
BpHunter22 years ago
How big of an object can it cut?
stevfuri2 years ago
Where can I go to find scrap materials? Is this a junk yard or a specialty store kind of thing?
foxfoxster2 years ago
nice job. thank you
69fordf1004 years ago
where do you find a pipe mount?
You can find a pack of them for a few bucks at a gas station.
jeb12482 years ago
Great Instuctable. It says that the acrylic was laser-cut. What did you use to do that?
I would really love to build this but I am waiting on your electronics instructable for this.
i'm starting to build this its realy nice and it will good to have your electronics instructable for connection this and a free programm to control it.
move it on
jsaxter3 years ago
i wanna cut the wood with laser what should i buy to build can you give me the information please jsaxter@gmail.com
GASSYPOOTS3 years ago
or use a cnc to make one XD
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