by Stargrove1, published

MicroCube by Stargrove1 Dec 4, 2016
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The MicroCube is a small, inexpensive 3D printer, designed around the cheap 28BYJ-48 stepper motors (files for Nema17 included except Z axis). The structure of the printer is based on an exoskeleton, which also serves as the smooth rods for the y-axis. The printer type is an H-bot style printer using a fishing line. In order to provide enough torque for the extruder, two steppers are used in series (or single Nema17 version). Due to the limitations of the 28BYJ-48 steppers, the precision is limited as well as the print speed (2-3 times slower than a standard printer).

Video of print: https://youtu.be/JlPdN9ktdqY


  • Low cost ~100€
  • Easy to build
  • Printable Area of 120mm x 115mm x 95mm
  • Small footprint 220mm x 220mm
  • Low noise during print (with 28BYJ-48 steppers ~50dB, with Nema17 ~60dB)
  • Upgradeable with Nema17 motors for higher speed and precision


2016/12/03 Version 1.0 Initial Version
2016/12/07 Video added
2016/12/18 Added Nema17 extruder and X/Y axis components incl. diagonal stabilizer
2016/12/27 Added assembly guide to the files
2016/12/28 Added part cooling fan, increased print quality
2017/04/02 Edited corner Nema17 mounts to also hold Nema14 motors
2017/05/14 Added spool compartment and spool holder
2017/06/05 Added PSU holder for Laptop supply

Print Settings

Printer Brand:

Robo 3D


R1 ABS + PLA Model


Doesn't Matter


Doesn't Matter





Custom Section



Printed parts:

4 x Corner parts bottom (Corner_bottom.STL)
1 x RAMPS holder (Ramps_holder.STL)
1 x LCD controller bracket, bottom (optional) (LCD_holder_bottom.STL)
2 x LCD controller bracket, side (optional) (LCD_holder_side.STL)
1 x z-axis bottom (z_axis_motor_mount_rod.STL)
1 x z-axis top (z_axis_bearing_mount_rod.STL)
2 x z-axis motor coupler (z_motorshaft_shaft_coupler.STL)
1 x z-axis bed platform (Z_axis_platform_mount.STL)
2 x z-axis bed holder (Bed_Lever.STL)
2 x End switch holder (Limit_switch.STL)
1 x Corner part front left (Corner_l.STL)
1 x Corner part front right (Corner_r.STL)
2 x Corner part motor (Motor_corner.STL)
1 x Motor mount left (Motor_mount_l.STL)
1 x Motor mount right (Motor_mount_r.STL)
2 x Motor pulley (Pulley_15mm.STL)
2 x y-axis carriage (y_carriage.STL)
1 x y-axis end stop trigger (y_carriage_endstop_trigger.STL)
1 x x-axis carriage (x-carriage.STL)
1 x x-axis wire holder (Wire_holder.STL)
1 x x-axis fan holder (Fan_holder.STL)
1 x x-axis carriage tensioner (x-carriage_tensioner.STL)
1 x hotend fan duct (Hotend_duct.STL)
1 x Extruder base (Extruder.STL)
1 x Extruder lever (Extruder_Lever.STL)
Cable clips small/big as required (Cable_Clip.STL/Cable_Clip_big.STL)

Nema17 upgrade:
1 x Extruder_Nem17_axis.STL
1 x Extruder_Nem17_Mount.STL or Extruder_Nem17_Mount_strip.STL
1 x Extruder_Nema17.STL
1 x Extruder_Nema17_Lever.STL
4 x Corner_stabilizer.STL

Spool holder upgrade:
2 x Corner_stabilizer.STL
4 x Corner_middle_motor.STL
2 x Spool_holder.STL
1 x 135mm x 8mm axis (aluminum tube from the frame)


5 x Stepper motor 28BYJ-48 5V (bipolar hack required)
3 x Nema17 motors (optional)
1 x 12V / 80W or more power supply (Laptop charger or for LED stripes )
1 x Arduino Mega
1 x RAMPs 1.4 Board
1 x LCD Controller (optional)
3 x 5S-5GL microswitches
1 x 30mm fan 12V
1 x E3D V6 hotend or China clone
1 x USB cable
1 x Power supply power cord
Ribbon cable to extend motor wires

Metal parts:

2 x Direct drive gear 11mm
6 x Smooth rod 8mm x 200mm
10 x Aluminium tubes 8mm (imperial 5/16 should also work) x 200mm (or other material)
8 x LM8UU linear bearings
2 x Springs for extruder (7mm x 30mm, strong)
4 x Springs for bed leveling (7mm x 20mm)
1 x Ball bearing 605 (14mm outer, 5mm hole, 5mm thick)
8 x U grooved ball bearing 604uu (13mm outer, 11mm inner, 4mm hole, 4mm thick for 1.75mm filament)
1 x M5 threaded rod ca. 160mm + M5 nut
6 x M2 x 12mm
1 x push fit tube mount M5
M3 and M4 screws and nuts

Nema17 upgrade:
2 x 8mm aluminium tube 230mm

Spool holder upgrade:
4 x Aluminium tubes 8mm x 200mm (or other material)
4 x Aluminium tubes 8mm x 120mm (or other material)
1 x Aluminium tube 8mm x ~130mm (or other material)


Zip ties 200mm x 3.6mm or comparable
shrinking tube
wires, pinheads
Print bed 4mm polycarbonat 150mm x 150mm
Pneumatic pushfit M5
Pneumatic tube ca. 400mm
~1.5m fishing line


For the use of the 28BYJ-48, the bipolar hack is required. A description how this can be done is available at http://www.electronicsmayhem.com/?p=13 , all 5 motors must be prepared as described. The wires of the motors are quite short and need to be extended, at this point, the connector could also be set in the correct sequence to match the RAMPs connector:

2B = yellow * (pin1)
2A = blue
1A = pink
1B = orange

At the RAMPs board, the current limit needs to be set before powering it the first time, following values could be used as Vref, fine tuning will be required due to production tolerances of the motors. During testing, X/Y/Z steppers didn’t lose any step, but they heated up slightly.

X/Y/Z driver = 75mV
E driver = 150mV


The printer is designed as an H bot, due to the small size, a fishing line is used along with ball bearings which are usually used in the extruder to guide the fishing line.
The extruder with two motors instead of one is used in order to provide enough torque for a direct drive bowden setup, the tension of the spring must be balanced not to harm the motors or gears but also to provide enough force for extrusion.


Firmware used for the MicroCube is Marlin 1.1.0 RC7, the configuration.h is provided along the files as a starting point to get the printer setup quickly. Here are some informations about the set values for the MicroCube:

Since Arduino Mega with RAMPs is used, Motherboard must be set to:


Mechanical settings sections holds the information about the kinematics, in case of the MicroCube setup following line must be set:

define COREXY

To match the mechanical setup with 200mm rods, the print area is set to:

define X_MIN_POS 0
define Y_MIN_POS 0
define Z_MIN_POS 0
define X_MAX_POS 120
define Y_MAX_POS 115
define Z_MAX_POS 95

Motor speed settings (28BYJ-48):

define DEFAULT_AXIS_STEPS_PER_UNIT {685,685,40758,1000}
define DEFAULT_MAX_FEEDRATE {30, 30, 0.25, 5}
define DEFAULT_MAX_ACCELERATION {300,300,1,10}


define DEFAULT_XYJERK 5.0 // (mm/sec)
define DEFAULT_ZJERK 0.01 // (mm/sec)
define DEFAULT_EJERK 1.0 // (mm/sec)

Motor speed settings (Nema17 version):

define DEFAULT_AXIS_STEPS_PER_UNIT {66.5,66.5,40758,96.1}
define DEFAULT_MAX_FEEDRATE {120, 120, 0.2, 10}
define DEFAULT_MAX_ACCELERATION {300,300,1,20}


define DEFAULT_XYJERK 5.0 // (mm/sec)
define DEFAULT_ZJERK 0.01 // (mm/sec)
define DEFAULT_EJERK 1.0 // (mm/sec)


Assembly guide added as PDF to the files (MicroCube assembly guide.pdf)

Sample prints

After setting up the printer and basic adjustment of the axis, 3DBenchy was printed as reliability test for the printer. The result was surprisingly good, picture of the first print along the picture section.


  • Nema17 holders (including additional frame parts for more stiffness) DONE
  • Improved extruder DONE
  • Include power supply (enough space available besides RAMPS) DONE
  • Setup guide DONE
  • Part cooling fan DONE
  • Endurance test

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Almost finished: https://www.dropbox.com/s/50611u75cgs8ygc/IMG_5717.m4v?dl=0 . One question though: How should I go about calibrating the stepper motors for this? It looks like everywhere I've looked for it's just an explanation of why CoreXY is better and HBot style printers should be updated to CoreXY.

I'm using Nema 14 for X, Y and Z axis and Nema 17 for the extruder. I know (I think) how to calibrate the extruder as I've already done it on my delta. Z-axis, I think I'll be able to manage a bit (however I've never dealt with lead screws or screw-based axis before). The main Issue I'm having is that the hotend doesn't travel the whole bed area (not even the 120x115 mm that it's supposed to). I've fiddled with steps per unit, but not sure if there's some math I should be doing instead of trying to guess.

Any help is appreciated!

Looks very nice, just one thing, I don't know if it comes from the video, but it seems that the pulleys at the motor are not 100% straight, this may result in non straight prints. I love the z axis, I hope find the time for a remix to improve mine too.

About your question, I recommend the 66.5 from my sample config for Nema, from this point calibrate it like described in many guides (http://reprap.org/wiki/Calibration section "X & Y scaling and steps/mm calculations"), control the axis for a defined value, measure the actual movement, calculate the deviaten in percent and add/subtract this percentage to the steps per unit. But I wonder why you are so far off, perhaps try to tighten the fishing line or add an extra loop around the pulley to avoid slipping.

About the calculation, here is the theoretical part:
Pulley diameter 15mm
Steps per rev 200 (1.8° motor)
Microsteps 16

Steps per unit = Steps per rev x Microsteps / Diameter x PI
Steps per unit = 200 x 16 / 15mm x 3.1416
Steps per unit = 67.91

I hope this helps you


Also, I took some pictures and it should be more clear that they're in fact not straight: https://www.dropbox.com/sh/b3yrs62hnjluium/AAAy6SGO5uIM82nzjfOnJ86Ka?dl=0. How is that happening and what can I do to fix it?

Also the fishing line I'm using currently stretches a lot but I'm waiting for another braided one, a proper one I hope.

Fishing line (or whatever you use) is not allowed to stretch at all, this may already be the root cause for slipping.

I could only guess why the pulley is not straight. The stl off course is designed to be straight, that means you have an issue with printing them properly, from my experience, it might be a problem with the cooling, at small parts it could happen that the previous layer is not cool enough before the next layer is printed, this leads to deformed results. You can try to improve cooling with a fan, reduce the print temperature (if possible), reduce the printing speed to cool down the layers or print the part multiple times, then each one has time to cool down while the same layer is printed at another part.

I think I found another issue I was having: It appears my Nema 14 are 0.9 degree stepper motors. I changed them for Nema 17s I had and the distance travelled with your marlin settings seemed to be on track.

The only problem now is the Z Axis which I need to calculate the steps per unit. I've tried multiplying by two (81516) steps / unit but it seems that I still get too large distance travels.

How did you come up with the 40758 steps/unit in your config?

If you have a different stepper angle, you have to recalculate the steps per unit, thats why the 28BYJ has so high values, the gears increase this value dew to the ratio of ~1:65.

About the z axis, in my example, the BYJ is still used for z-axis (I want to change that too if I find the time), so you have to recalculate by the formula:

Thread pitch = 0.8mm (M5)
Steps per rev Nema 17 = 200
Steps per rev Nema 14 = 400 (your case)
Steps per rev 28BYJ = 32606.1824

Steps per unit Nema 14 = Steps per rev Nema 14 / Thread pitch
Steps per unit Nema 14 = 400 / 0.8
Steps per unit Nema 14 = 500

You should also increase the speed and acceleration values

Oh man, I'm really impressed right now! This one is really cute! What an amazing job, congrats!

Thank you very much, you're far too kind

Just an idea I had if anyone wanted to make this a portable printer with heated bed.... would build one but half way through another build


How is this 3D printer accurate?

Actually I can't tell, in the 28BYJ-48 version accuracy is limited due to the mechanical play of gears, with Nema17 accuracy is comparable to any other printer. Have a look at the sample prints. By calibrating the printer the results are very good, but I can't state any numbers

I want to make 3D assembly in solidworks. How I can convert models in STL. to SLDPRT(solidworks) or other.

Use the open dialog and chose .stl then go to options and chose volume model and open a part. That should work according to Google:

Nice!!! Sehr schön


Progress update (gallery with videos): https://www.instagram.com/p/BWlGUqoFUId/

Finished the design for the z-axis (wider, with 22mm bearing and NEMA 14 mount) and got the firmware (Teacup on an Arduino Uno with a CNC shield (to stay true to the whole concept)) running.

Comments deleted.

I have already been asked in the comments about using an Arduino Uno + CNC shield to further reduce costs. Would you share the firmware for easier use? I could add it to the MicroCube Thing or you can create a remix which I could point to.

Since I'm going with a belt-driven NEMA14 setup, I have to redesign basically every part (already finished a good chunk (using OpenSCAD)) - sharing the source files (as a remix) and the firmware was the plan all along. :)

But for the firmware/config files I'll be going with a git repository. This way it's easier to document and keep track of (possible) changes.

The last missing hardware parts I'm currently waiting for are the idler pulleys. Once they have arrived I can finish the axis and start tweaking the firmware settings (motionwise).

Ok, cool. I also have been asked about a belt driven version. Will you keep the h-bot style or move to core-xy?

Nice, I'm curious how the core xy will look like and how it will perform

I'm going to try a core xy setup (for reasons). We'll see how that goes.

What are you thoughts about using this printer design with less cheap components? I want to build one with a heated bed, an e3D Titan with the NEMA17 upgrade.

I am running the printer with the Nema17 motors for a while now and I would definitely recommend it, the speed of the 28BYJ-48 motors is simply to slow. Better components will lead to a better performance, the Titan might not reach it's full capacity, since the speed is limited by the h-bot style, but in this case you might use it in another project. I am running the printer with a Titan and E3D clone and it works pretty well.

Can you tell me what the spacing is for the carriage rods? I have a serviceable CoreXY printer at the moment, but the carriage design is lacking, and I rather like the one you've designed here.

The rods are 36mm apart from each other

Got all the parts, about to make one, but I have a question: Can you use the cheap 28-byj motors for the xyz movement, and use a nema motor for the extruder?

As OkurRo mentioned, yes you can. Actually, the first motor I replaced with a Nema17 was the extruder since the solution with two 28-BYJ motors is quite weak and slow. You need to adapt the steps and you can also increase the speed in the firmware.

how do i increase the speed in the firmware, which line?

Have a look at the description or Marlin in general:

define DEFAULT_MAX_FEEDRATE {30, 30, 0.25, 5} // X, Y, Z, E

For Nema motors, you also need to change the steps values and acceleration

Yes you can, only steps per mm will be diferent on extruder motor

Awwww its so cute!!! I might have to make on but make the Z axis taller.

Extending Z axis should be no big deal, simply extend the length of the vertical rods. But don't extend too much, rigidy is based on the small size.

yes i know, I'm keeping that in mind .

What size are you aiming for?

Z of about 175 or 200, i know that might cause some structural issues but ill think of a way to brace it.

I wish you did something for nema14

I thought of using Nema14, but they were quite expensive to get here in Germany. But if you like, I could add a bracket for the X/Y motion system, its pretty simple.

I edited the Nema17 holders, I added the holes for Nema14 motor, now you are able to mount both motors on the bracket, you can even exchange them without cutting a new fishing line. Please let me know if you give it a try, I am interested in the result since I thought of using the Nema14 myself

Thank you that would be very nice

Hi I have access to aluminium shaft (it's not hollow), can I use it? I asked because I saw a hole in the corners that seems to go straight into the tube, what is it for? Mounting the motor?

EDIT: Nvm, it's for the top bearing, so I guess the motor and bearing mount doesn't have nut trap?

Hi, yes you could use solid material as well as a hollow tube.
For the z motor no nut trap is used since the force is quite low to keep it in place. The bearing is held in place by the same screws + nuts which are used for z-axis rods.

I thought of lowering the price by using uno, cnc shield and relay for hotend. Do you think that it's possible?

Marlin is not compatible with the UNO, however there is a firmware which is designed to run on an Uno (and other controllers) https://github.com/Traumflug/Teacup_Firmware.
So yes, should be possible, but a little additional hardware needs to be added because the CNC shield does not provide a driver for the hotend.

Do you have any resources for adding a hotend to a CNC shield? It would be nice to have a cute small controller to go with the cute small printer :)

Also you could use carbon fiber tube for the frame and even the linear slides, they need either Igus bushings or printed PLA or PETG bearings.

Instead of adding the hotend to the CNC shield, I would suggest to use a MKS board which combines the Arduino Mega and the Ramps board in one single pcb (http://www.ebay.de/itm/New-MKS-Gen-L-3D-Printer-Controller-Board-Compatible-With-Ramps-1-4-Mega-2560-/162433300401), otherwise you need to copy the MOSFET schematic of the RAMPs board which will end up in a higher price and mor effort.

Carbon fiber is a nice idea, haven't thought of it yet. I decided to use the aluminum because it was easier to source and machine. I also wanted to keep it as cheap as possible.

I'm building one with CF rods and a few different parts:

I've got a flat Nema 17 (22mm length), 8mm threaded rod and would like to use gt2 pulleys and a single PCB from a Delta printer. I'm looking to mod the designs a bit and see if I can make it work, any chance you can release the source?

This is a picture of my progress so far (not a lot) https://www.dropbox.com/s/8jqulv1qizw4uuu/Photo%20May%2020%2C%2022%2011%2025.jpg?dl=0

Btw, I love the concept and your design! Thanks for sharing it!

Wow, looks cool, I like the colour scheme as well. I hope it works well with the carbon rods.

Which parts would you need for your redesign? I also got a pancake stepper, I would be interrested too to upgrade to a Nema17 z axis. I found that the platform is not very rigid, needs also an improvement.

For now I need the z axis motor mount, and the bed platform so I can fit the pancake Nema 17 with the bigger and heavier 8mm leadscrew. I still got some parts on their way from china so this is probably not going to be finished anytime soon, but I can let you know what other parts I need to modify as things arrive and I can progress.

As for rigidity, I fear the frame might not be heavy enough and that the center of mass being offset to the upper middle and close to the motors, due to most of the weight being on the back (as it appears in the photos).

I'm planning to move the motors to the front or filling in the front rods with sand trying to move the center of mass closer to the middle/bottom. Maybe some support pieces might also be needed.

Send me a private message with an email addresse to send the files. When adding the pancake, can you update the platform to accept both, M8 nut as well as T8 brass nut, I was planning to use one.

Rigidity of the frame itself is great, especially with the diagonal stabilizer, issue is the bed itself, I tried to reduce printed parts as much as possible, but the arms are to weak at the front.

Its also stands quite stable on the desk, of course, I don't know about the light carbon fibre version, I use a Laptop power supply which I want to integrate behind the display. This will make it more compact too.

Yeah I have MKS BASE and MKS GEN-L boards, but I wanted something even smaller to match the printer :) I was hoping there was some easy circuit to add a hotend to a CNC shield but I guess not. Oh well. A Melzi or RAMBo would also be a good choice. I like the all-in-one boards better than cheap RAMPS shields which tend to have poor quality.

Carbon fiber rod is getting pretty cheap these days due to quadcopter guys. HaoZhong Carbon Fiber on eBay reportedly have very good accuracy and consistency with sizes. It's cheaper for me in Australia to get carbon fiber than anodized aluminium. Cheaper still to get hardened steel smooth rod, but that's also very heavy.

I think a MKS or another single pcb would fit great compared to arduino combined with a shield which is more bulky.

Besides the price, I wanted to avoid cutting the carbon fiber, aluminum is easy to cut and file. But if you are going to build one, I would love to see a built with carbon fiber and a single board solution.

I also plan to add the Laptop power supply in the free area besides the Ramps board and an extension for the spool to get everything more compact.

I will definitely let you know if I do it. At the moment I've got the parts on order for a HyperCube, so I'll spend a few months getting that working well, then start on a new project.

I'd actually like to remix this design into a CoreXY, enlarge it slightly with 250mm tubes, and keep everything except the Bowden tube inside the frame. I've got a few other ideas like acrylic panels on bottom/back/sides for stability and for mounting things to and for the look, using a laptop power brick and buck converter, and having the build surface as boro glass with an easily removable clasp for convenience.

I'd like to use NEMA14s but high-torque ones are not cheap. It would make more sense to upgrade my main printer's motors, and use the old NEMA17s to build this thing.

Everyone wants to go big these days, here we are talking about smaller printers :)

Very cool. I will make this soon.

On the parts list you say -

6 x Smooth rod 8mm x 200mm
10 x Aluminium tubes 8mm x 200mm (or other material)

I have smooth rod, but what is the tubes? Where are they used and can you provide a source (aliexpress?) for them?

Thank you,

The tubes are used for frame. It can be any 8mm pipe. Alumminum are better for frame so just try hardware store, or some store for house and garden.

The smooth rods are used as part of the frame as well as for the linear motion of the x/y/z axis, for the other frame parts, I used cheap aluminium tubes with 8mm outer dimension from a local hardware store, but you could use any material you want (aluminium, steel, carbon fibre, etc.), solid or tube. Amazon link: https://www.amazon.de/gp/product/B00ZXPJ0QC/ref=ox_sc_act_title_1?ie=UTF8&psc=1&smid=A1P3ZJ39C3CUTD

Thanks. I am in the US. 8mm kind of hard to get. I look for conversion and looks like 5/16 is pretty close.
I will keep looking for 8mm.

K&S makes 8mm aluminum tubes. Check a local hobby shop for them (though those in my area only ever had 1 or 2 in stock), or you can get them online, from the likes of Tower Hobbies etc. They run ~$2 for one 300mm tube.

If you are in region where the imperial system is used, it is also possible to use 5/16 rods, the corner clamps should work as well as with 8mm

Maybe try call a metal company, I am getting the bar from an aluminium extruder manufacturer. Maybe this will be easy in the US. Tubes will be hard to find, but solid bar should be easy.

As I am from Germany, metric system was used. But I think the 5/16 should work well, there is enough tolerance, the corners are like clamps tightened by the screws. If it should not work, use some kapton tape around the rod to fill the gap.

I wish we would switch to the metric system....

Think I found something, I'll get these - http://www.ebay.com/itm/271607850532

Tubes are almost here, time to start printing the parts!

Printing last part now.. Looking over the instructions, are you consistent with your use of Tube versus Rod or did you mix the two?
For example, step 1, assembling the frame, 4 x Aluminum rod 200mm. Then it jumps to talking about Z axis rod, which should be smooth rod. I want the frame to be tube.

I did a search for Tube in the instructions and found something around step 12 or 13 and 16 only.

I can probably finger it out but thought I'd ask for clarification.

All parts of the frame which are not used as a linear guide, are made of aluminium tube. The linear guide requires smooth rods. Have a look at the pictures, you can see the difference between the two types.

Printer is coming together. Need to wait for more parts (bearings) to arrive. This is a nice and simple design, really happy with how easy it is coming together.

I broke the X carriage applying the zip ties on one side but not the other.

Couple questions:
Any sources for the print bed?
Regarding fishing line, it has been many many many years since I have been fishing, It seems that kite string might also work for this. I had some of that around here somewhere. In the event I can't find it, what type fishing line did you use?

I'd go with Spectra line.

There is nothing special about the printbed, I used a piece of polycarbonate, other material are fine too, I got it from the local hardware store.
I just ordered a fishing line from Amazon, I guess kite string would be good too, it is just important that the material is not flexible to achieve precise positioning.

MADE!!! I posted a make. This was a fun build and everything was working GREAT even dimensional accuracy, THEN I HIT RESTORE FAILSAFE SETTINGS in Marlin firmware and now the extruder does not seem to extrude enough material. Can someone help? I am using the NEMA17, 26t pinion. Using values documented in PDF file, Motor speed settings (Nema17 version):

#define DEFAULT_AXIS_STEPS_PER_UNIT {66.5,66.5,40758,96.1}
#define DEFAULT_MAX_FEEDRATE {120, 120, 0.2, 10}
#define DEFAULT_MAX_ACCELERATION {300,300,1,20}
#define DEFAULT_AXIS_STEPS_PER_UNIT {66.5,66.5,40758,96.1}
#define DEFAULT_MAX_FEEDRATE {120, 120, 0.2, 10}
#define DEFAULT_MAX_ACCELERATION {300,300,1,20}
#define DEFAULT_XYJERK 5.0 // (mm/sec)
#define DEFAULT_ZJERK 0.01 // (mm/sec)
#define DEFAULT_EJERK 1.0 // (mm/sec)

These values also appear when I look at the EEPROM, everything matches, wish I backed them up before I overwrote them. hehe

Fixed extruder by setting steps/mm to 100.00, after calibrating.

Still one thing that is wonky -

I have max X and Y set to 150mm.
In Cura (have not tested anything else yet), I have print bed set to 150 x 150.

When I save gcode and print the file, the output is not centered on the bed, but basically Y min and X min (top-right corner, opposite home).

See my make!

I don't know why the extruder setting stopped you printer from working, but I'm glad you solved it.

About the print bed center, I don't know which picture you mean, but I think the reason might be that the printer is only capable of printing at an area of 120mm x 115mm. If you set 150mm square, the calculated center will be off the actual center. Try to set the actual values of the printable area and check again.

Did the benchy test print work fine?

I thought of Nema Z axis as well, I bought an flat Nema17 already, but didn't find the time to implement yet

oh a pancake stepper, of course.

I will use 120x115 dimensions are retest.

The benchy prints GREAT on this printer. See my Make.

I tried printing a bigger object and the printer drifts to the right. Is there a bug in Marlin RC8 Bugfix?

I think I saw you were using RC6, maybe I will switch to this. Can you confirm what version you are on?

Actually it'S RC5 of Marlin, I also realized this shift, I increased the tension of the fishing line a bit, this reduced the shift. I suspect a slight slip at pulleys, maybe it would be better to use more loops at the pulley, it's also possible that the chamfer was no good idea. Still need to do some testing, but at the moment I focus on other things like finishing the MPCNC in the basement ;-)

I turn up current going to steppers and printer is fine!

Thank you for the feedback, guess I have to recheck the current. Glad to hear that it works fine now.

Very good project! I love small 3d printer
Is the h-bot sistem good? I read on internet that someone have problem with this configuration, but I think if you print slow there is no problem.
I will made this project with this cheap stepper https://www.aliexpress.com/item/2-Phase-4-Wire-35-Stepper-Motor-0-9-degree-20mm-3D-printer-Stepping-Motor-35H20HM/32677700359.html ( 4 of this cost only 20$ ), Do you think that they are good?

Thanks for sharing this project!

Thank you. I haven't had issues with the h-bot style, I also think the combination of slow speed and the small size makes it less vulnerable.

The steppers look good for x/y, but for the direct drive extruder it will be to weak. But perhaps you could use a different geared extruder, then it might work.

I'd love to see your result in the made section and also a comment about the small Nema17 motor performance

Hi, I have done the bipolar hack with steppers but only one is working rightly. Most of others are now moving only in one direction and moving only every third/secong step. The other one is moving right and left without me changing direction, but only in about 20 degrees. Did anything similar happened to you?

Hello, I didn't have such issues. I have done the hack with five motors and they all worked fine.

Try to check the following points:

  • Is the connection completely interrupted? Do you have a multi meter to check?
  • Are the coils connected correctly? Compare the wiring with the working one.
  • Have you flashed a firmware with correct steps/mm, to fast might end in unexpected movement
  • Have you set the current of the drivers to the values as described?

I hope this helps in finding the root cause.

Thank you, it was wiring and damaged driver.

Glad to hear that you fixed the issue. How far is your built? Is the guide detailed enough for setting up the printer?

I have added video of first tests.

Yes it's detailed enough. I'm still waiting for delivery of endstops and i don't have the buildplate yet. Right now i am placing fishing line.

im building a micro cube just wondering Motor_mount_Nema17_r file is there a left hand file as well or do i just use this one twice


I forgot to add to left one, please check the files, I added the second holder. You would to mirror the part, but they are not the same due to the mount holes. Thank you
I'd love to see your printer at the made section

What an incredibly engineered little bot! Thanks for sharing

Thank you for your kind words

Hi, could you please add some scheme about wiring of fishing line? And how come the fishing line isn't sliding freely around the motor wheel? Is there any specific one which is sticky or something?

Hi, I am about to write the setup guide, the assembly will include a step about it. The scheme is quite standard H-bot, you can find a lot of examples in the net. It's a standard fishing line, I simply wrap it one and a half time around the coupler and with the required tensioning it does not slip at all.

Edit 2016/12/27:
Have a look at the assembly guide, you can find the scheme of the fishing line in the description.

Hello, do you think it would be possible to NOT hack the 28BYJ-48 motor, but instead use drivers meant for this motor? http://www.ebay.com/itm/1Pc-ULN2003-chip-Module-Stepper-Motor-Driver-Board-Test-Board-For-Arduino-NEW-/272462871114?hash=item3f700d7a4a:g:ThMAAOSw5cNYOG0F
And if yes, do you know how to wire it into RAMPS 1,4?

Hi OkurRo,

I am afraid this will not work, there are two issues, first the stepper driver of RAMPs is designed for bipolar steppers only (motor is a unipolar model with a simple transistor driver, the ULN2003). The other issue is the fact that the stepper motors will not have enough torque, in unipolar mode, only half of the coil is used, while bipolar mode uses the whole coil by inverting the voltage. If you are afraid of hacking the motors, you don't have to, all you have to do is cut the connection between the two coils. It is very simple.

Comments deleted.

you could use acrylic sheet in the 3d printer as in enclosure and it will make it stronger

Yes you are right, but when I designed the printer, I tried to use only printable or easy to source parts to make it easy to build, acrylic parts should be cut on a cnc or laser cutter, I don't have access to like many others. I will try to add additional diagonal rods for the Nema17 version.to have more stability.

hay what is the name of the Ball bearings, 13mm outer, 11mm inner, 4mm hole, 4mm thick or from where you buy it

Hi, the bearing code is 604uu, I added the names of the bearings to the list. I found them in a German 3D printer online store, but you will find several stores in the internet selling them.

Hey, nice work! I don't know the limitations of these steppers but I guess that some lateral / back / bottom crossbeams would increase stiffness a lot and, maybe, allow some more speed.

+1 for video(s)

Thank you, the steppers are very slow because of a gear ratio of 65:1 they are already at their limit. For this speed the structure is well enough. But you are right, when I add the Nema17 upgrade, I will have to check the influence of the frame at higher speeds.

required nema 17 fixation and gt 2 belt fixation.
i m sorry bed english

As described, I will add a set of holders for the Nema17 for the XY axis. Belt would require a bigger rework which is not planned by me, I am not sure if the structure is strong enough, have a look at one of the existing core xy printers, they already offer the belt Nema17 combination.

Could you add a video showing the printer in action ?

Yes I will add a video along with some more information about how to setup the printer.