Smooth X-axis for Prusa i3 with Leadscrews

by MazaaFIN, published

Smooth X-axis for Prusa i3 with Leadscrews by MazaaFIN Nov 1, 2015

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NOTE: X-MOTOR.STL and X-IDLER.STL are made for 22mm spacing

UPDATE 15.5.2016

  • moved X-stepper mount point 5mm to left for 21mm version (X-MOTOR_21mm_WIDER.STL)

UPDATE 14.2.2016

  • made parts with 21mm spacing for Geeetech i3 pro c

UPDATE 29.12.2015

  • I had identified wrongly the idler bearings my printer came with. They're F693ZZ, not F623ZZ. With latter GT2 belt could not move freely. I have modified the clearance of the belt tensioners arm part so that both bearings should now work.
  • Updated belt tensioner arm part is added as own file for those that have printed the complete set before.

X-axis with fixed X-endstop and finger adjustable belt tensioner. Nothing new compared to already published (like ffleurey's thing:169636 and jkoljo's thing:372056). It's just this smooth looking design I like and wanted to share it.

Note that there's no spesific Z-endstop trigger point as I prefer inductive proximity switch (mounted with the extruder).

The distance between Z-axis's smooth rod and leadscrew is not same in all Prusa i3 versions. The kit I bought from Aliexpress.com is having 8mm acrylic frame and designed with 22mm distance but it seems that 17mm is more common. Also in Geeetech I3 X the distance is different, 27mm.

  • I have made necessary modifications and now there's X-motor and X-idler for 17mm, 21mm and 27mm distance too. Please inform me if the design has any faults.
  • stepper motor mounting point is moved 5mm to the left in X-MOTOR_27mm (Geeetech I3 X)

GT2 belt ends should stay in place without zip-ties. My printer is fixed in enclosed cabinet so belt removal is easier and doesn't require removal of X-carriage.

Required hardware
2 x F623ZZ (3x10x4) or F693ZZ (3x8x4) flanged bearing (idler)
4 x M3 20mm recessed head screw (stepper + idler)
1 x M3 nyloc nut (idler)
6 x M3 12mm hex socket screw (leadscrew nuts)
2 x M3 10-16mm hex socket screw (tensioner)
2 x M3 nut (tensioner)
1 x M4 20-30mm hex screw (tensioner)
1 x M4 nut (tensioner)

Print Settings






0.2 - 0.25 mm layer height


30% honeycomb


All parts have necessary built-in supports. X-idler's "comb"-supports are 0.5mm width. If slicing generates problems with these, try to change default extrusion width to ≤0.5mm.


Supports should be easily removable. X-endstop has tiny supports, that I carefully cut out with small blade.

If you find there's not enough room for smooth rod, carefully ream the holes with 8mm drill bit. Design clearance is only 0.05mm.

Note that X-axis's smooth rod may not be exactly coincident with X-idler's right end when assembled. It is essential that there's no bending of Z-axis's rods when X-axis moves along it. Take your time to achieve this before tensioning X-belt.

Belt tensioner block has separate guidance piece that should be glued in right place. Make sure there's no binding between this piece and mating hole in X-idler's right end when assembled. Idler bearing holder should also move without binding. Design clearance is 0.25mm in all sides.

Before adjusting belt tension, make sure there's small gap between tensioner block and X-idler's right end to prevent bending the Z-axis's smooth rods and leadscrew.

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Hi guys
I need help !!!
i need an extruder holder for this x carriage.
Thanx ))

Which one is for the anet a8?

Am I missing something? The current screw hole configuration for bolting on the lead-screw fitting seems impossible to use (at least on the 21mm spacing version). There's not enough room for a bolt or even the head of the M3 next to the bearing holder shaft. Hope this makes sense. Love the design, but I couldn't get it to go on properly... once I magled it enough to go on it wasn't very structurally sound, haha. I appreciate that your sharing this great design though, and I realize you probably don't have the printer for this one and were just trying to help by providing it... I'm not complaining, just curious if I'm missing something :)

There needs to be a variant for a Z-Trigger as not everyone uses an inductive probe

Is there a good Thing or other mechanism to decouple the x-ends from Z?
I need to prevent Z wobble

Thank you for your good job with this =)
But can you upload STP files on X-Carrier?
Need to move the holes a bit

Anyone have part numbers for the 8mm linear bearings for X AND Z would like to use Igus.

I really like your design and i would like to use it for my Anet A8.
i would need to use the regular 22 mm version but i figured that the Motor mount would have to be 10 mm wider from yours, as Z wouldnt get far down enough and gets stuck at the frame.
Is it possible for you to make a 22mm wider version?
i measured +10mm
Thanks in advance

I would appreciate that too! Mounted the 22mm on my Anet A8 and unfortunately they diddnt fit. Saw this posting too late....But I like those brackets so much!

I really appreciate the level of detail here. Good job.

Hi, can you please give me a link to the z axis top bottom rod- motor holder stl . I printed the version with small distance rod -lead screw . I cant find it anywhere. The ones i tested the x axis is pushing the lead screw .. Thanks in advance :)

You should print correct X-motor and -idler (there's 17, 21 and 27 mm versions) AFTER you have measured the distance between lead screw and Z-axis smooth rod in your printer. The distance is not standard.

Apr 13, 2017 - Modified Apr 13, 2017
Odys - in reply to MazaaFIN

My distance is 17. The problem is when i print the z axis parts that hold the motor and smooth rod they make the x motor mount to push the lead screw.Means that the parts of the z axis are less than 17 . Thanks for the respond.

Why are there 2 arms in the stls?

Two different lengths to choose from.

Apr 6, 2017 - Modified Apr 6, 2017
mohag519 - in reply to MazaaFIN

Ok thank you very much. One more question. The arm really didn't fit into the idler piece. Does that mean I am over-extruding? I feel like there can't be more than just a few percents in that case because the models come out very nicely with no blobs or irregularities otherwise. Would 1-2% of overextrusion really make that much difference? I had to file down the arm and the idler quite a bit. Are they a really tight fit in usual case?

Quick prints of few small parts can explain your problem. Smaller parts tend to deform even when extrusion rate is correct. Use active cooling or print multiple parts at the same time.

After trying to assemble everything I encountered more and more pieces that wouldn't fit. For example all of the m3 nuts were close to impossible to get in. I think my ABS is perhaps bad quality and shrinks extremely. I will try from scratch with PLA or ABS with everything 2% biigger.

Geeetech? They have the wrong steps/mm by default resulting in slightly incorrect print sizes. After correcting mine parts are perfect... all of this was perfect too except it seems the STL's are slightly modified, and the screws for the lead-screw fitting are almost impossible to get in with the new configuration.

same problem here.

Mar 17, 2017 - Modified Mar 17, 2017

Just finished making this for the 'Geeetech i3 X'
The 27mm variant fits perfectly with no modification to the spacing between the lead screw and guide rods!

The only part that needed to be modified were the X-axis smooth rods which needed about 50mm cutting off them for the tensioner to be fitted correctly. I would have prefered not to have cut the rods should i wish to make a wider bed/frame at some point, but considering how bent they were out of the box it was for the best anyway!

Works a treat and is miles better than the OEM acrylic parts, think it's also taken almost a Kg off the X-axis overall when combined with a Bowden setup LMAO

Only problem i've noticed is the lack of a Z-axis Min stop adjuster... In my mad rush to get the new parts installed i failed to notice this until i was just starting to re-calibrate! Oops!

Overall 5/5 Strongly recommended upgrade!
Keep up the good work MazaaFIN

Hi. Does anyone knows the part number for the little microswitch x- end stop ? Also for z end stop what should I install ?

Omron Micro Switch D2FC fits perfectly. They're commonly used in computer mouses.

sweet! I just robbed (2) from an old mouse!

MazzaaFIN Thank you for your reply.

Im finishing the print right now, just a question about the belt tensioner: In a picture I can read :belt tensioneing tend to bend the rods towards teh bed..." And I have to adjust the screws till I get a little clearence between the tensioner and the idler. What is the purpuse of this clearence?

so the sensioner does not squeeze the x mounts together , it pushes against the x-smooth rods (horizontal) instead of putting force on the (vertical) z-rods and possibly bend them

hello, can you place the STEP file hier?

which set do I use for the Anet A8?

I believe the 21mm. Based on the Z motor mounts Ive printed for my Anet A8, its definitely not the 27mm. I plan to print these this weekend. Will let you know my results.

So which variant fits the Anet A8?

22mm - So the files that don't have a variant label.

Feb 16, 2017 - Modified Feb 18, 2017

Is it possible to get the 17mm ones with 16mm diameter for the bearings? I am using the IGUS RJZM-01-08 and they have a 1mm larger diameter than the LM8UUs.

I have a prusa i3 that I built from a BOM. Using a standard aluminum frame I am getting some clearance issues.

Clearance issue #1 X axis motor is so close to my ramps board that it was actually shorting it out.
Clearance issue #2 if you are using motors with couplers instead of motors with built in leadscrews, the Z axis barely has enough clearance to zero out the nozzle on the bed.

otherwise I love this set. Just have to jerry rig something until I can get a more permanent solution to my clearance issues.

Mar 17, 2017 - Modified Mar 17, 2017
Fix3r - in reply to prozach

issue #1
Don't invert the X axis stepper, leave it on the front with the drive gear facing the back as before. The new part is symmetrical front to back and can be done without any issue!

issue #2
Probably be easier to remake your nozzle/extruder mount to bring it say 5mm lower? That would stop any clearance issues with your lead screw couplers.
I can't vouch for the Aluminium Prusa but i have couplers on my acrylic frame and my Bowden setup zero's on the Z axis with the bowden heat sink almost touching the bed without putting a min stop adjuster screw on!

I am not sure what you are trying to say with issue #1. My x axis drive is on the back and has always been on the back. Even in the example images for this object the motor is on the back of the left bracket.

Issue#2 wasn't really an issue for me. I have enough clearance, just barely. Just had to redo my Z endstop.

Ahh, apologies... Was thinking of the clone Prusa's which seem to have the stepper motor on the front and the drive gear facing the back of the machine.

But my suggestion still stands if you are still having clearance issues between the motor and the board. I'm just uploading photos on the 'i made one' look for the yellow print with an 'X axis' label on the stepper, it will make sense then! (teaching the mrs to use the printer and she was getting confused with x,y,z)

Thank you great work

How do I assemble the belt tensioner?

Belt tensioner block has separate guidance piece that should be glued in right place. Check the picture.

I made a remix of the endstop to use on the Anet A8 printer


End stop remixed
by Bakchos
Jan 25, 2017 - Modified Jan 26, 2017

So ive printed the 27mm and the 21mm.....27mm version the rods stick out way to far to put tensioner on. 21mm version pulls the rods to close together and the 1mm difference in the 22mm version wouldn't make a difference...

Should update this and tell people if they use the 27mm version they will not be able to use tensioner as shown in the photos !

Almost in tears over this and am so horribly pissed off!

WOAH, slow down Clwebb. This is a free design that you downloaded on a free website to use free of charge on your 3D printer. I get that you are frustrated, but rather than gripe at people, why not take the 3D files into a program like Tinkercad, 123D, or Sketchup and modify them to do what you need them to? Then, you can post a remix of this to help other folks who might be having the same problems as you :)

I'm sorry the parts aren't compatible with your printer.

Jan 26, 2017 - Modified Jan 26, 2017
Clwebb - in reply to MazaaFIN

I have a Geeetech Acrylic....How are they not compatible? Sorry to be such a piece of shit about this but I have tried and tried and tried and it just does not work! I could just use a bit of help but no one seems to helpful around here..

Chinese printers aren't made with "standard" dimensions. Variant models may have different rod lengths etc.

Maybe you can adjust rod length with bi-metal hacksaw or order pre-cut?

I'm sure you'll get your printer working after some adjustments. I remember having a lot of frustration at start too.

I already have cut the rods and still no go? I really do not understand how people with the exact same printer as mine install this then?

Check you haven't swapped rods between X-, Y- and Z-axis?

I've had problems with tight bearings (Igus) before when printing other Idlers. Do you think I can scale it up by 1-2% ?

They should fit without scaling, if your printer is calibrated right.

Thanks for the design this great, I have printed but the belt does not fit.

Check that your printer is calibrated right.

Comments deleted.

Why do you use the open-source logo on this design yet you refuse to provide the Solidwork files as it would "be too easy to publish remixes"? That is very strange.

Regardless, they are simple models and it wouldn't be that hard to backward design them to improve on the design. If I publish anything, I definitely won't be publishing it as a remix, that's for sure.

I'll remove the logo if I publish upgraded files.

Why not just publish the cad files and be done with it. My application requires a 28mm rod/lead screw spacing. I'd give you full credit if I posted any changes that I made. Why re-invent the wheel. I would also like to know why you chose to use Open Builds logo, and then NOT post the CAD files. Maybe Open Builds can answer that question. ;)

Do you mind letting me know why you are against publishing cad files of your design? It's so odd to me. Your design is not unique, even the only relatively complex part (belt tensioner) is not your own original design.

Are that worried about your design being too easily remixed? What? Why would you want to make it harder for people to improve on your design????

Especially considering you put the open source logo on there in the first place, and then you go against everything open source stands for. Makes no sense to me. An explanation would be appreciated. Thanks.

Thanks for the great work! I just upgraded my Anet A8 with these parts. I also designed a tensioner arm for use with 16-teeth idler pulleys. These don't fit in the provided arms so I just made one for my A8. Check it out at: http://www.thingiverse.com/thing:2037208

X-Axis Tensioner Arm for toothed Idler Pulley

Hi, Thanks for your File.
With the original Design, and i use 16-teeth idlers as well, it seems the belt ist not parallel.
it look slightly pulled up on the top.

could you see this as well?

Glad you liked it!

I have not experienced any trouble with the belt not being parallel. Since the part is a tight fit for the holding block, you might need to sand it down a little more to give it some "wiggle space". Otherwise it may be pushed off-center by jamming it in the block.
If the problem still persists, you might also want to try to reposition the toothed pulley on the motor slightly to make your belt parallel.

I made this on my alunar prusa i3 and had a problem with the belt. The old setup had the belt being held a the bottom of the x-carriage, when this one has the belt being held on top. It switched the direction of my x axis. The motor is set to spin clockwise to bring the carriage back toward the endstop switch on the left, but now since its being held on the top instead of the bottom it wants to head right instead of left. Did anyone else have this problem or am I missing something?

In S3D, there shows no support, should i go for fast or full Honeycomb?
Will it come out with support even tho its not showing in S3D

it seems in S3D it will print in the air for the top where the belt is going..

The parts should print without any additional supports, just keep the extrusion width ≤0.5mm. Honeycomb infill is OK.

Jan 16, 2017 - Modified Jan 16, 2017
w4rr3n - in reply to Zoulburner

For motor side there is no support. I did a fast honeycomb.
Personally printed them without support, the only supports are from the file and they will only show at below 0.5mm extrusion width.(The supports will not print if it is not showing in S3D.) Just have to make sure you printer can bridge proper.

I wanted to use it on my Anet A8 but it seems that even the "wider" Version is not wide enough. Do you mind adding a eben wider Version? Another 5mm should be sufficent. Thanks.

I just printed this for my A8 and the 22mm fits just fine.

did it print with support even tho it doesnt show in the preview?

I made the X-motor and X-idler and had problems to get one of the three nuts for the brass guide in place. The hole is too close to the body, had to melt a slot with soldering iron to get the nut there.

please make a 30mm edition for vertical x-axis for mendel i2..!

Comments deleted.

Just replaced the 5mm rods on a vanilla Prusa i3 with your (17mm) set of parts to convert it to acme rods and get belt tensioning on the X axis.

It went together well, test prints pre & post show a great improvement in results - great upgrade, thanks :)

Do you have a source for the acme rods and nuts? Also, how to change the firmware/software for the thread difference.

Dec 3, 2016 - Modified Dec 3, 2016

Did anybody designed an adapter for a simple 8mm nut with 8mm Threaded rod to adapt the 5mm derlin Nut?

I need this too. Please let me know what you find.

Hi, elegant work @MazaaFIN!
I was curious - what have you been using for your y-endstop?
You mention that you are using OMRON Micro Switch D2FC. Do you use the same micro switch and how and in what have you fastened it?


Great desing!!! Smooth and stylish without loosing functionality. Only thing missing is Z Endstop adjust screw mount.

Thanks for the contribution

Did you find a solution for the missing Z Endstop screw mount?

Nov 1, 2016 - Modified Nov 1, 2016

could you please make this X rods holes 10mm besides 8mm? thanks!

Dear @MazaaFIN, thanks for your awesome job, I'm looking this kind of X-Axis for a long time and this design solved my problems, but the thing is I just bought the M5 leadscrews to swap my old threaded rods. Do you have any idea how to modify the leadscrews nut to be M5? Because I don't see any SCAD or similar files in there. My plan is, later on, I can drill a bit when I upgrading to M8 size or maybe re-print the whole design. Many thanks if you can help me about this.

My child got ill so I haven't had time to make the parts you requested. Can you confirm the nut is same as in the link below?

I'm so sorry to hear that, I hope your son get well soon. And btw, yes that's the same nut I'm using now. Thanks a lot @MazaaFIN

I'll make modified versions on weekend when back at home. Check the leadscrew nut dimensions, is it same as this:

Thanks for sharing these designs with us. Do you happen to have the 17mm files without the supports? The slicing software I use has added more support material and it becomes difficult to remove. Thanks again.

It's highly recommended to disable supports on slicing software. All files are ready to print. If you really need supportless STL, send me your email by private message.

Anyone know a extruder mount for the e3d titan that will fit on this?

I liked the built in removable supports on this. I'm looking for a tutorial or explanation on how to design these when I work on my own models. One of the things I think it could come in useful for is when I'm printing a tall object and I want to attach another tall object for stability so that it won't work itself free of the bed. I'm having trouble finding the right search term for this though. Any help is appreciated.

I'm not sure what you're meaning. Maybe a picture or STL-file would help?

I just printed the 21mm version and there isn't enough room for the nut on lead screw closest to the rod on either end of the X axis. other than that it looks great, tensioner works great also

The nut hole is 10.20mm for snug fit. You could ream it with 10mm dril bit.

? it's an M3 screw. if you look through all the peoples build photos everyone has their ball screw flanged nut affixed with only two M3 screws as the 3rd screw hole doesnt have room on the backside for a M3 nut. a small indention on the outside of the linear bearing housing part would allow for the installation of a 3rd M3 nut.

What do you mean by 21, 22, 27mm etc?? What spacing is that for?

Look the first picture, parts are for 22mm setup.

Aug 16, 2016 - Modified Aug 16, 2016

Just curious - I'm needing to reprint both ends of my x axis for my Geetech i3 Pro C. I like your remix better than the original but I'm still using the standard 8mm threaded rod (works fine for me) - is there any reason why I wouldn't be able to use that with your design? I have the propper brass nut thing (looks like the one in your pictures) for my threaded rod

Should work fine.

this is awesome! what x endstop switch should i use? as my current one looks far to big to fit

Nice to hear you like it!

Omron Micro Switch D2FC fits perfectly. They're commonly used in computer mouses.

brilliant ill get one order

just thinking would i need to make changes to the carriage im using? i dont think it would work but i have it setup perfectly atm and dont really want to mess about with it. youre a legend if you know


X carriage for i3 X

This is such a fantastic design and so well done. It's a shame it doesn't use standard 624 bearings for the idler. The idler is simple enough though. Would only take a minute to make one up. Perhaps I will comment with a link to it when I make it.

Thanks for your compliments! The idler bearing is what I got from chinese Prusa i3 kit. Please leave a comment/link when you have done the idler for 624.

Ahhh, okay. That makes sense. And yeah, I will leave a comment here and be sure to attribute it properly.

By the way, what software did you use to design this? And what did you use to make those diagrams? Very nice layout. Not only good for presentation, but very helpful for instructional purposes.

Everything was made with Solidworks. It's pretty cool tool.

Really? Awesome. That's what I use too. I didn't know about the diagramming capabilities though. I'll have to explore a bit more.

Dear MazaaFIN,

Can I use PLA?

Sure you can.


can i adapt for LM10?
Thanks in advance for your reply

There's version for LM10 bearings http://www.thingiverse.com/thing:1257584

Smooth X-axis for LM10UU

thank you very much MazaaFIN

Hi great looking system, I'd like to give it a try on Samuel rework I'm building, but the screw\smooth rod spacing is 30mm. Any chance of a quick re-work.

Thanks in advance

Jun 13, 2016 - Modified Jun 14, 2016

Hi, you can make for prusa i3 sunhokey?

What would be better for the Z bearing?1 lm8luu or 2 lm8uu?

I recommend using two LM8UU bearings. I have found no use for LM8LUU.

May 17, 2016 - Modified May 17, 2016

idler does not fit with the standard idler wheel - the gap on the idler arms what do i use their guess i need to order new bearings..

I printed the 21mm version for the geeetech. Everything fit great until I reinstalled the motor side on the rods. The Motor is rubbing tightly against the side of the acrylic frame. Is there anyway you could make a version that moves the motor 5mm or more to the left in relation to the rods?

It's done, moved X-stepper mount point 5mm to left. The file is named X-MOTOR_21mm_WIDER.STL

I can do that when back at home (on saturday).

What Printer frame is the used for ive built it but realized it isnt for my hictop prusa that being said i love this set up and would like to beable to purchase a frame for this message me please

Bought the kit from Aliexpress.com. There's multiple versions, main difference is distance between Z-axis smooth rod and leadscrew. You just need to print the right parts.

I started putting together a custom build where i was planning on using the 10mm x-carriage mockup you made for someone until i noticed that my z spacing is going to be different. Is there any possible way that you can help me out by providing the 10mm design with a 19mm spacing ? I would appreciate it very much and it will allow me to continue with my design without any modifications.

Thanks again.

Sure, I'll make modified parts in following few days.

Awesome, thank you, i really appreciate the help. I honestly thought that most of these double z motor printers all used close to the same spacing. I was wrong.

19mm parts are now ready to download: http://www.thingiverse.com/thing:1257584

Smooth X-axis for LM10UU

Thank you, I will print them tomorrow and let you know how they look. I really appreciate the help.

They Look good, good enough to go forward with the 10mm upgrade. Again, thanks for the .stl's.

Comments deleted.

Is there any particular place online where you can buy all the parts ?

What Kind of Microswitch do you use ??

Hi, thanks for the model ! I have printed the 22mm part first, but it seems that my version of geeetech i3 Pro B have in fact 21mm spacing... So i decided to print 21mm parts but I found that the circle-shaped parts are not as smooth as the 21mm ones. I checked with netfabb, and there is clearly less triangles in the 21mm parts, as you can see on that link :


Is it possbile for you to re-upload smoother files for 21mm parts ?

Hey, what happened with the original 22mm parts? my printer running of 22mm , but i cant find them :/

X-MOTOR.STL and X-IDLER.STL are made for 22mm. I'll change the file names on next update.

Hey have you thought about 10mm smooth rods. I am having problems with mine not perfectly straight in both X and Z. So I am thinking of going 10mm are you keen to do a version with 10mm rod holes and 10mm bearings holders?

Already done for grtbaldini's setup: http://www.thingiverse.com/thing:1257584

I can make adjustments if needed. Haven't tested the parts myself.

Smooth X-axis for LM10UU
Feb 23, 2016 - Modified Feb 24, 2016
ant0ny - in reply to MazaaFIN

EDIT: I just changed this to reflect a change of direction.

Ah thanks I missed this. I'll have a look and a think and post back on the specific item page.

I am going to build a Wilson 2 printer next with all 10mm smooth rod etc so I will do the I3 upgrade after I do the Wilson 2 build.

Feb 15, 2016 - Modified Feb 15, 2016

Hey, what happened with the original 22mm parts? my printer (hesine m505) seems to be running of 22mm like yours too, but i cant find them :/
EDIT: nevermind, forgot about the normal one being it. sry ^^

Hi thanks for the model. Can you also post a 21 mm spacing for pro c? I already printed out 22 mm spacing and will change it but after reading the comment below about pro c i doubted it will not goes well.

Now there's X-motor and X-idler with 21mm spacing too.

thanks for the effort :)

Sure, I'll make the parts on next weekend when back at home.

Ist there any chance to enhance this model with an anti z-wobble thing?

Hmm. The solutions for Z-wobble aren't particularly convincing. I would get better quality parts for Z-axis.

Jan 26, 2016 - Modified Jan 26, 2016

Any chance of updating this with a version that uses screws to hold the z-axis bearings in place? Similar to http://www.thingiverse.com/thing:372056? I find your overall design far superior.

Prusa i3 improved XZ axis
by jkoljo

The bearings should stay in place without screws. The radial load on Z-axis's bearings is light so additional clamping force seems unnecessary. I want to keep the design simple.

Thanks for your compliments!

Jan 25, 2016 - Modified Jan 25, 2016

Nice design though I prefer the stock LM8UU retention design on the z axis (https://github.com/josefprusa/Prusa3/blob/master/box_frame/sample_stls/single_plate_gt2_lm8uu/x-end.stl), I've yet to get the bearings out of the design used on this part without breaking the printed part, can just let up the screws on the stock design to get the bearings out easily.

You don't need to break the part to remove the bearings. Use flat screwdriver to spread out the opening and they come out easier. I haven't had need for quick disassembly feature as this setup works so well.

Thanks for your comment!

Hey any chance to make these for 10mm smooth rods? I wanted to try a more rigid version... Thanks!

What is the distance between leadscrew and smooth rod in your setup?

I have the MendalMax 1.5 with Klugineer's x ends. Im not at home to give exact dimensions at this time. I appreciate the response and will get back later today. Off hand my x axis rods are approx 16 1/2" long

So this is what I have now. http://www.thingiverse.com/thing:21705 My rods are horizontal in these and from the leadscrew to the rear rod is 24.50 mm. If I can implement the vertical rod setup like yours, I'd prefer to use the 10mm smooth rods. If that won't work I still have my 8mm to use.

Bind-Reducing X Ends for MendelMax & Prusa and MendelMax.com precision leadscrews

This would be a whole new thing to make. As I don't have Mendel -type frame, I wouldn't be able test the parts myself.

Maybe you could do it yourself? Check the dimensional drawings (downloadable PDF-file) for reference.

I hope you get the spark. :)

I will certainly have alook at it. Thanks for taking the time to respond.

Using a screen capture of the pdf file allowed me to import into sketchup were I was able to outline where needed and then extrude. I have a long way to go but I think it's gonna happen!

X Axis
Jan 10, 2016 - Modified Jan 10, 2016
MazaaFIN - in reply to grtbaldini

I thought you need Mendel -type parts (X-smooth rod side by side). Are you using 10mm smooth rod both on X and Z axis? What is the distance between Z-axis smooth rod and leadscrew in your printer?

Jan 10, 2016 - Modified Jan 10, 2016
grtbaldini - in reply to MazaaFIN

I'm planning on rotating my x axis rods 90 degrees to mimic the Prusa design sorry if I wasn't clear before. I have 10mm smooth rods on my z axis currently and converting from 8mm to 10 mm on my X axis in a vertical position. the z axis smooth rod and leadscrew is 30 mm center.

Check the X-motor part I made. If it seems to fit, I can rework the other parts too.


Smooth X-axis for LM10UU
Dec 29, 2015 - Modified Dec 29, 2015

I had identified wrongly the idler bearings my printer came with. They're F693ZZ, not F623ZZ. With latter GT2 belt could not move freely. I have modified the clearance of the belt tensioners arm part so that both bearings should now work.

I have finished revising this to fit the GeeeTech prusa i3 with 21 mm spacing. This came out perfect. WELL DONE!! I like it. I haven't printed with it, but I love it. I think it looks much better. Just waiting on a new X limit switch.

On my version I added the Z limit screw to hit the switch and even revised it for lead screws. Will post soon, was also part of a complete Bowden extruder conversion that I made.

I'm glad to hear that!

Whats wild, is I have the prusa i3 pro C and the spacing between the Z threaded rod and the Z smooth is 21mm. Seems Geeetech changes crap all the time. Now I have to modify this to work with my printer. After I printed out the ones I thought would fit found that none of these are right for the printer I have.

Why don't they just leave something alone! LOL

Strange it is. I could make customized parts with 21mm spacing if needed.

Very easy to add in a tab to put a allen screw through to hit the original z stop. Just need to visualize it on your already printed part, put on the printer move it towards the z switch. Once you see where it needs to be, open up sketchup and add in a tab with or without a nut trap reprint and your done. I know its a waste of filament for what you already printed. Your other option is like davidsmake said, add a inductive sensor. OR, you can come up with your own setup.

I have just printed the X-MOTOR-27mm for my Geeetech Prusa i3x, but i have just realised that there's nothing to trigger the z-endstop. Any ideas ?


Unfortunately this setup is designed without any specific Z-endstop position.

I recommend you get an inductive proximity switch: they're cheap, easy to install, very accurate and make the Z-endstop obsolete. You need aluminum bed though.

LJ12A3-4-Z/BX Inductive proximity switch, NPN, normally open (http://www.aliexpress.com/wholesale?SearchText=LJ12A3-4-Z%2FBX). Works without any additional electronics.

I am actually printing the X-MOTOR-27mm for my Geeetech Prusa i3 X, i'll give you guys a feedback once i put the whole assembly together.



I suspect X-axis smooth rods are different length and may require shortening the recesses in X-motor part.

Everything with GeeeTech is off. I had one as a starter printer and yea, it caught fire and burned literally. They gave me way too small PSU, said it was a 350W. After it burned up that and the gt2560 board and looked, the psu internally was only designed for 200W.

Regardless I love the work and since I still have parts from it, I am going to use these to fix their printed part junk they sent me. Let me tell you ALL parts I received were printed Ion an un-calibrated printer, at super low resolution. NONE of the parts fit, I ended up filing most of it until it all worked correctly. AND their acrylic pieces were all broken. Their new printers look more promising. I have 2 flash forge creator pro's and couldn't be happier! I miss the print volume of my i3 though! that's why I want to rebuild!

Huh, you have had exceptionally bad experience then! The kit I got from China was apparently better quality but there wasn't any mechanics for adjusting belt tension.

Hope you get the i3 back in business!

Nov 16, 2015 - Modified Dec 16, 2015


I have a Geeetech i3x 8mm Acrylic and the Z smooth rod to lead screw (8mm) pitch is 27mm. The x carriage is 45mm pitch on the smoothrods which I think is standard.

Would you consider a resized Z carriage? I like your setup and professional drawings you must do this for a living i'd guess.

Nov 16, 2015 - Modified Nov 16, 2015
MazaaFIN - in reply to ant0ny


I suspect the Geeetech i3x may have other dimensional conflicts with Prusa i3 too. I uploaded X-MOTOR_27mm and X-IDLER_27mm so give them a try and tell me if they need any adjustments.

Thanks wasn't expecting such a quick reply... having a few issues with prints but as soon as I sort this out I'll print and report back... again thanks.

Dec 16, 2015 - Modified Dec 16, 2015
ant0ny - in reply to ant0ny

Ok I printed all the X/Z parts and did my upgrade... here is a quick summery:

Geeetech Prusa I3 X 8mm Acrylic


Repetier version 0.9 supplied by Geeetech using Sli3cer

The Parts printed without support perfectly but I had a few small problems more to do with my version Prusa I have.

X-MOTOR_27mm: I had to mount the motor facing backwards as it was "just" touching the frame. Maybe move the motor mount about 5mm more away from the Z Smoothrod for clearance.



X-endstop: The switch supplied with mine was bigger so I re designed my own.


Belt Tensioner: the I3 X has a slight different approach to the "bending Z rod issue". They have 2 Locking collars to reduce this and as you can see in the pics I have retained them.

The only issue I had was the clearance of the belt and the idler bearings. The I3 X used 2 x 624ZZ bearings for the belt (4mm bore 13mm OD 5mm width) I had to find smaller bearings to make it work.


Just a few more pics:



Thanks for your comments! I'll make some adjustments and update the files.

Dec 16, 2015 - Modified Dec 16, 2015
ant0ny - in reply to MazaaFIN

No probs.

One thing with the X idler bearing I just realized you allowed 8mm for the bearings you use and these from my STD setup are 2 x 5mm so 10mm wide. I also noticed that the head of the screw if not fully counter sunk almost touches the Lead Screw.

So maybe look at sticking with a clearance for 8mm idler bearing space but give a little more room for a 12 to 13mm diameter bearing size plus the belt thickness.

I am using 2 tiny 2mm wide bearing with a 3mm hole then a 9mm printed sleeve but it's a little narrow about 12mm would be good size.

made most of the components, but also added 2 small knobs on the pins that go through the tensioner, to stop the belt
tensioner end from moving


M3 bolt nob

What kind of leads screws did you use for the project? And do you have the SolidWorks file for that and are willing to share these i might make some changes

The printer came with built-in THSL-300-8D leadscrews, 8mm pitch, exactly 400 E-steps / mm (1/16 microstepping).

Unfortunately I don't want to share Solidworks files as it would be too easy to publish remixes. I hope you understand. I can make the changes you need, just give me details.

Hi MazaaFIN, first of all well done.

If you modify a thing which was open source (right now I don't know if the license was CC-SA or MIT license or whatever), you have to release it opensource again.

Even tough I can't understand why you don't want to share the SolidWorks file, could you at least post plueprints or even step or IGES files? I could tell you what modifications to implement but then it would be complicated because I will print and test and then give feedback...

It's boring to do the reverse-engineering on the STLs I hope you could provide at least the plueprints

Hi there! I'll try to find time to update this thing in following few days, with detailed drawings.

thank you!

tried to print the 17 mm idler but only half of it printed, file is damaged

OK, inspected the G-code you sent. You use Pronterface so slicing with Slic3r I assume.

The G-code is ending on layer 105 = Z15.0mm when printing solid infill. The layer height seems to change between 0.1 and 0.2mm's many times. You used additional supports, that might be causing this? Brim is OK.

I suspect the slicer you use is really confused with the next layer's already included supports and outputs incomplete g-code.

Try to slice the part without additional supports. The small prebuilt supports are designed 0.5mm width so that can be set into slic3r's default extrusion width if the problem remains (nozzle diameter need's to be around 0.4mm).

I recommend previewing g-code to check it's complete. There's online viewer's too: http://www.3dgeni.us/gCodeViewer/index.html

Send me the new g-code with these parameters changed, if printing still fails.

The print goes:

  • from 0.00 mm to 120.73 mm in X and is 120.73 mm wide
  • from 0.00 mm to 190.00 mm in Y and is 190.00 mm deep
  • from 0.00 mm to 61.00 mm in Z and is 61.00 mm high
    Estimated duration: 202 layers, 1:28:57

I used Skeinforge in ponterface to slice it this time as slic3r output the height at 15mm even after I made the changes you suggested, are the size parameters correct now?

Part is sized 39.60mm x 34mm x 60mm. Values you gave may refer to part's placing on build plate but still abnormal.

Could you send me the G-Code-file you got from Slic3r/Skeinforge to see what has changed, though I'm not familiar with Skeinforge. I could check the slicing parameters - from Slic3r, choose File - Export Config (or Config Bundle). You can safely change outputted file's endfix to ".txt" if email you're using doesn't allow unusual attachments.

Nov 3, 2015 - Modified Nov 3, 2015
MazaaFIN - in reply to drummerman

Mesh looks OK in netfabb - 1 shell, no holes. What slicing software you used? Does the gcode preview look OK? If possible, send me the gcode-file you tried to print for investigation. I'll send my email address with private message.