Introduction: 4xiDraw

This project was inspired by a commercial product called AxiDraw that I saw a video of recently from Evil Mad Scientist Laboratories.

It was a combination of reasons that made me consider to do it myself, cost, availability and customs playing a role in the equation (that, and having a 3D printer at home).

This is just a drawing machine quite similar a to a pen plotter but that can adapt to any size of document and any type of paper.

It can use regular felt-tip pens, ball pens or fountain pens as pen orientation is variable. It is a new version of an XY plotter using a single belt and two stepper motors in a configuration called h-bot.

Step 1: What You Need

Picture of What You Need

I started the project using laser cut parts but eventually evolved the model to 3D printed parts. So you can grab the STL files of the printed parts from here or here.

Bill of materials

  • 2 nema 17 steppers (*)
  • 4 8mm smooth rods (two 400mm-long and two 320mm-long)
  • 8 LM8UU
  • 2 20-tooth GT2 pulleys
  • 10 F623ZZ bearings
  • 1 micro servo SG90 (plus a 250mm cable extender)
  • 1 Arduino UNO
  • 1 CNCshield
  • 2 Pololu stepsticks
  • 1 GT2 belt ( 1.4 meters long )
  • 2 M10 threaded rods (400mm-long each)
  • 8 M10 nuts
  • 8 30mm M3 screws with nuts
  • 8 6mm M3 screws
  • 4 16mm M3 screws with nuts
  • 4 M3 washers
  • 2 4mm OD, 100mm-long carbon fiber tubes
  • 2 15mm M3 screws
  • 1 12V 2A power supply
  • 1 USB cable
  • 1 felt tip pen (or many for more fun)

(*) Stepper motors should be 40mm or shorter, unless you chose the taller parts that I later created for some users willing to use 48mm tall steppers (like many use for 3D printers).

Step 2: Assembly

Picture of Assembly

There is a live 3D model you can see for yourself in here. The explode feature may give you an idea of what is inside of another part. Or you can download STEP model or access Onshape CAD design from Thingiverse.

I recommend the following building sequence:

  1. Slide two LM8UU in each of the two longest smooth rods.
  2. Slide the rods into the motor pieces, one on each side (leave an extra 20mm of the rods in one of the two sides protruding from the part towards the motor, this will later be used for supporting the Arduino holder).
  3. Insert the M10 treaded rods so each one supports one side of the motor-supporting pieces using a nut on each side (total 8 M10 nuts).
  4. Mount the nema 17 stepper motors on the two big plastic parts using 8 M3 screws (8mm long).
  5. Insert 8 M3 nuts into the nut-holders in the bottom squared carriage and place it supporting the LM8UU linear bearings you inserted in the long smooth rods already installed.
  6. Take the remaining (shorter) two smooth rods and insert two LM8UU linear bearings on each one of them.
  7. Insert the two endY parts on each end of the pair of smooth rods. Now you have the second axis done.
  8. Insert the top square carriage over the 4 linear bearings of the shorter smooth rods.
  9. Insert 4 M30 30mm-long screws in the 4 central holes of the top square carriage, put the carriage upside-down carefully so the head of the screws will lay on the table and the screws will point upward.
  10. Insert one F623ZZ bearing with the flange down, next an M3 washer and finally another bearing but now with the flange up) into each one of the four screws of the top square carriage.
  11. Use a post-it or a similar-size piece of paper to press it against each one of the screws protruding so paper is perforated and is pressing against the top of the bearings. The goal is for this paper to hold them in place while we put the whole thing upside-down preventing the bearings to fall off.
  12. Place the top carriage over the bottom carriage so the smooth rods on the top form a right angle with the bottom smooth rods.
  13. Screw lightly each one of the four M3 screws and once you notice each one is attached to the nut in the bottom tear the post-it paper apart. Next finish tightening the screws and add the other 4 M3 30mm screws that do not have a bearing but add strength to the union of top and bottom parts of the carriage.
  14. Place one GT2 pulley on each stepper motor but do not tighten the grub bolt yet.
  15. Place a pair of F623ZZ bearings with an M3 washer in between fixed with an M3 screw in the end Y part that will support the servo part.
  16. Insert the belt all along its path (the crossings of the central carriage are a bit tricky). And once pulleys are aligned with the belt tighten the grub screws on each one.
  17. Use two M3 screws and two nuts to attach the servo support part and later add the microsevo using the two screws that come with it.

  18. Make sure the vertical two holes in the servo support part are 4mm diameter and that the carbon fiber tubes can be inserted into them (if not, drill the holes with a 4mm drill bit). Insert both tubes from the top but only mid way. And next insert from the top the vertical carriage (the one that looks like a smiling face). Gently push it down till you can insert the remaining half of the carbon fiber tubes so they are inserted into the bottom holes of this carriage.

  19. Using a couple of M3 screws and nuts fix the pen-holder part to the vertical carriage.

  20. Push the Arduino holder into the protruding smooth rods on one of the stepper motor holders. Use a couple of M3 screws to attach the Arduino board to the plastic holder.

Congratulations, the mechanical assembly has been completed.

Step 3: Load Arduino Firmware

Picture of Load Arduino Firmware

This project uses a special flavour of GRBL software created by robotini user. It enables GRBL to handle a servo on digital pin 11 using commands M3 and M5. This way it can raise and lower the pen on the paper.

Installing the software is better explained here, please read it carefully as some people may find it difficult as is not the typical Arduino program (in essence the code is created as a library).

How do you know it is all working?

You can connect using the Arduino Serial Monitor to your board at 115200 bps and a welcome message: grbl 0.9i ['$' for help]

Step 4: Wiring Everything Together

Picture of Wiring Everything Together

Before inserting the CNCShield over the Arduino you want to do this trick, that will allow to power everything from the Arduino power jack. Failing to do this connection from Vin to + header on CNCShield most likely will make your servo not to work properly.

On top of Arduino you insert the CNCShield board and on top of it, two of the Pololu StepStick stepper driver boards. But before inserting these two boards for axis X and Y, make sure you put three jumpers in the headers (that will later be obstructed by the Pololu carrier boards).

A three-wire cable will be coming from the servo and two four-wire cables come from the stepper motors.

Servo cable has to go to (red) +5V, (black) GND and signal (white or brown) to Digital pin 11. Servo cable is too short, so an 250mm extension cable will be needed.

Each stepper motor goes to X and Y axis four pin headers on the CNCShield.

There is an optional improvement: make the plotter wireless by adding a Bluetooth module, but I would only do this once everything else is up and running.

Step 5: Computer Software You Need

Picture of Computer Software You Need

There are two types of programs to use in your computer (until someone creates one that does both): one for creating the code for a given graphical design. And a second program to send the code just created so the plotter will draw it on paper.

For the first part I use Inscape free vector drawing program with a plugin I hacked. Install may be a bit tricky for the non tech savvy user.

For the second part I use UniversalSerialGCodeSender Java program that allows you to load the file created with Inkscape and send it to the plotter.

You want to setup the proper scale for your machine, but that is not stored in GRBL firmware but on the Arduino UNO EEPROM memory. So you will need to set that right before starting to draw. (Following text comes courtesy of Erivelton user):

  1. Access from the terminal (commands tab) of the Universal Gcode Sender, the settings of your firmware by typing $$
  2. Check the parameters $100 and $101. They define how many steps are required for the machine to go 1mm.
  3. Considering that you used a 200-step motor, a 20-tooth pulley, and the GT2 belt (2mm pitch), the correct values for both parameters would be 80.
  4. If they are not with these values, type “$100=80 + Enter” on the terminal to adjust the X axis. Type “$101 = 80 + Enter” to adjust the Y axis.
  5. Ready, your machine will now draw exactly the same dimensions as your Inkscape drawing :-D

Update: Torsten Martinsen has brought to my attention his work on another plugin that will take care of sending the drawing to the 4xiDraw from within Inkscape software, so no need for UniversalSerialGCodeSender nor for another plugin this way. You can get his plugin here:

Step 6: Final Touches

I think this a fun project can easily take a weekend to get it done (depending on your skills).

This is my first instructable and I can see there is yet much more that could be said about the details of the project, but once the basic stuff has been laid out I would try to improve it by addressing user comments.

And if you would like to say thanks in ways different than a comment, you are welcome.


misan (author)2017-12-07

If you want to use Bluetooth you need to make sure the Bluetooth module is configured to use the same baudrate the Arduino is (115200 bps in the firmware I use). You can use the same software (Universal Serial Sender) that you used with USB, just change the serial port to the Bluetooth one.

HamdiA3 (author)2017-12-04

How i can make the plotter wireless by adding a Bluetooth module !?

misan (author)HamdiA32017-12-04

You can use the guidance provided here

And you still use the application on the PC side but now use the bluetooth serial port instead of the USB one.

HamdiA3 (author)misan2017-12-06

I did everything as requested but did not work
I could not send data by bluetooth

HamdiA3 (author)HamdiA32017-12-04

And which app i can use ?!

HamdiA3 (author)2017-11-15

It's amazing. But how can I make the rotation angle of the servo motor 50 degrees instead of 180 ?!

misan (author)HamdiA32017-11-16

M3 S controls the motion of the servo, use different values from 0..255 to get the angles you need.

panuche (author)misan2017-11-16

Ok muchas gracias por su contestación

panuche (author)2017-11-16

Hola esa especie de plástico que usáis para que los cables del servo no se enreden qué es exactamente y dónde se puede conseguir

misan (author)panuche2017-11-16

Yo he usado tiras de plástico recortadas de una lámina de polietilieno de las empleadas para las portadas de trabajos encuadernados con gusanillo.

KhurramC3 (author)2017-11-13




misan (author)KhurramC32017-11-13

Thingiverse link contains the DXF for laser cut parts. If you are good with the saw you can cut it by hand from plywood. That should be cheaper in case you do not have access to a 3D printer or laser cutter.

KadirÖ1 (author)2017-11-02

Hi Misan,

What is the use of M3 washers between F623ZZ bearings?

Thank you.

misan (author)KadirÖ12017-11-02

Hi KadirÖ1,

The washer is for the inner races of the bearings to contact to each other leaving the outer ring to move freely.

Maxymilian (author)2017-06-10

Hello misian,

I already build similar plotter like yours, but I have a problem with a drawnings.

My machine draws diagonal pictures (they are kicked 45 degree)

I spend all days with Universal Gcode Sender Settings (invert pictures, changeing speed axies, and so on), but it still draw diagonal.

I have been changing grbl settings and uploaded to arduino until I burned voltage stabilizer (arduino is working yet).

Need some help, advise.

Thanks in advance.

misan (author)Maxymilian2017-06-10

45 degree rotation is usually due to not having enabled COREXY on GRBL firmware.

minhhung9999 (author)misan2017-10-26

anyone can help me? im new at this so its hard to me to fix my problem.

when i send g-code file to arduino it shows up:

error message: "Grbl has not finished booting" please help me. thanks a lot

misan (author)minhhung99992017-10-27

It seems related to Universal Gcode Sender

Can you control GRBL from Arduino's Serial Monitor? Uploading GRBL to Arduino maybe tricky the first time, try to follow the instructions carefully

SreeR18 (author)2017-10-16

what are the changes do i need to make if i use a 16 teeth GT2 Pulley instead of 20 teeth in software

misan (author)SreeR182017-10-16

X and Y scale is $100 and $101 EEPROM parameters on GRBL.

burock54 (author)2017-10-09

**** Connected to COM3 @ 115200 baud ****

Grbl 0.9i ['$' for help]


Skipping command #0

Skipping command #1

Skipping command #12

Skipping command #41

Skipping command #76

Skipping command #104

Skipping command #122

Skipping command #146

Skipping command #164

Skipping command #181

Skipping command #190

Skipping command #207

>>> G21

>>> G90

>>> G92X3.00Y3.00Z0.00

>>> 0S30

>>> G4P150



>>> 0S30

>>> G4P150

>>> M18

>>> M01

>>> M17

>>> G1X-71.73Y-61.62F3500.00

>>> 0S30.00

>>> G4P150


error: Expected command letter

>>> G1X-70.61Y-61.62F3500.00

>>> G1X-69.58Y-61.95F3500.00

What is my problem ?

misan (author)burock542017-10-10

0S30 is not a valid command, other than that it is not easy to tell from your output.

burock54 (author)2017-10-09

hello. ı made it :))) very thanks but ı have little problem. I using lnkspace ı draw and make gcode. but ı send my cnc machine but dont work. ^^ error name is : ''error: Expected command letter

>>> G1X-75.08Y78.91F3500.00

>>> G1X-75.08Y67.09F3500.00'' why dont run my gcode ? thanks

burock54 (author)2017-10-08

This project uses a special flavour of GRBL software created by robotini user. It enables GRBL to handle a servo on digital pin 11 using commands M3 and M5. This way it can raise and lower the pen on the paper. Hello ı dont understand what is meaning M3 and M5 commands ? what must make ı do? because ı bought new micro servo sg90 it's too dont work. ı use z+ for servo signal cable thanks

misan (author)burock542017-10-08

Hi Burock54,

M5 is the same as M3 S0

M3 S20 means to rotate 20 units the servo.
M3 S50 means to rotate 50 units ... and so on
M3 S0 means the servo should go to 0 degrees angle (units are not degrees but proportional to that).

If connecting to your GRBL the servo does not respond to different commands as the ones above there is still something wrong in your setup (as I guess you connect GND and +5v to power your servo besides the signal pin).

burock54 made it! (author)2017-10-04

hello ı made it but i have problem. ı connected servo motor signal cable to end stop z+ of cnc shield but servo motor is rotating always and ı dont use bluetoth module. if ı connect servo motors signal cable Z blue pin of cnc shield, is rotate just one direction. how can ı make this ? Thanks.

white cable is signal cable of servo motor

descort (author)burock542017-10-04

Hi burock54,

I've looked at your CNC shield and you have wired the signal to the wrong pin. I'm not sure what the pins do tbh, but you need to use the endstop pin Z+ on the other far side of the picture.

burock54 made it! (author)descort2017-10-04

hi descort. Thanks information.

But if ı wear signal cable to z+ servo motor is always rotating.

burock54 made it! (author)descort2017-10-04

hi descort. Thanks information.

But if ı wear signal cable to z+ servo motor is always rotating. u can see on video

misan (author)descort2017-10-04

Hi burock54,

Please note connecting 12V to the CNCshield is not advisable. Use the Arduino power input jack instead. Some users reported broken USB chip when using that configuration.

misan (author)burock542017-10-04

If servo rotates one or more revolutions it means you have the wrong type of servo.

burock54 made it! (author)misan2017-10-04

is wrong type?

burock54 (author)burock542017-10-04

It enables GRBL to handle a servo on digital pin 11 using commands M3 and M5. what is meaning ?

wunderkindsakura (author)2017-10-01

Hi, I intend to make this project, and the steps you have listed are very detailed and great, thank you! :)

I just have one problem, I have no idea how 3D printing works, so if you could just enlighten me on how to use those .stl files you have provided, it would be very kind of you. I'm a newbie at this and I don't understand from where can I provide the dimensions of the parts in the .stl files.Please help! :(

JacksonV6 (author)2017-07-22

I'm getting a warning on inkscape saying "Warning: Your selected object is part of a group..."

I've tried to ungroup it but still have problems. Any ideas?

misan (author)JacksonV62017-07-23

There may be groups inside groups that might need more than one ungrouping operation.

JacksonV6 (author)misan2017-07-23

I got it working now. Only problem is everything mirrored and the Z axis wants to go up instead of down. How do I go about reversing these? I know that $3 inverts the x and y, but not sure if I'm doing it right. On your Gcode files it works fine but others it does not. How do I invert z axis? Thanks so much.

imrankazi (author)JacksonV62017-10-01

I am also getting mirrored prints, I did all the options from the firmware , reinstalled inkscape and plugins, please update me if its solved

snadol (author)JacksonV62017-09-24

Well, it seems like it's not your machine that's inverted, but some part of the software you have. I only think that because it works well with other files, but not the ones that you used. I would suggest uninstalling and reinstalling your Inkscape and Turnkey laser exporter.

DeadlyDad (author)2017-09-24

Hey! Great project! I was planning on building something like this next spring, and this would work perfectly. The difference with my build would be the size. I want to print custom clothing patterns, so I want to have a ~1m * ~2m draw area. How difficult would it be to change the STL's to spread the bars out to minimize racking? Could it be done in Thingiverse's Customizer?

misan (author)DeadlyDad2017-09-25

You have the Onshape CAD linked in Thingiverse (which is linked from the instructable too).

I have created a 1m x 0.7m version using 8mm rods and I could not recommend it.

DeadlyDad (author)misan2017-09-25

Good to know. What issues did you have with the larger size?

misan (author)DeadlyDad2017-09-25

problems: balance, too much play, motors may not be powerful enough for a larger version, difficult to carry around.

snadol (author)2017-09-24

I made one! I also have a tip for anyone who wants their machine to move faster.

There are caps on speed in the Universal Gcode Sender. They are defaulted at 500 mm per minute, but you can change that. They are commands $110, $111, and $112. I recommend 3000 mm per minue as a safe speed. Also, If you do that, change commands $120 - $122 to 100.

snadol (author)snadol2017-09-24

I forgot to add, to change commands just put $[command number] = [value]. So to change command $120 to 100, I would write $120 = 100.

TuấnV17 made it! (author)2017-08-16

Thanks Misan for this great project! (author)TuấnV172017-09-15

Hey TuanV17, this 4xidraw is not yours!!

francescop29 (author)miguel.bi2017-09-20

sorry, have you the correct stl to connect servo motor to z carriage? thanks (author)francescop292017-09-20

Ciao Francesco, Puoi trovare qui la versione Misan:
Oppure la mia:

snadol (author)TuấnV172017-09-19

Those are the exact pictures and words that used. That is their submission, not yours!

About This Instructable




More by misan:4xiDraw
Add instructable to: