by 3DAndy, published

MiniExtruder by 3DAndy Jan 24, 2013
0 Share
Download All Files

Thing Apps Enabled

Order This Printed View All Apps



MiniExtruder by 3DAndy is licensed under the GNU - GPL license.

Liked By

View All

Give a Shout Out

If you print this Thing and display it in public proudly give attribution by printing and displaying this tag.

Print Thing Tag

Thing Statistics

15466Views 4187Downloads Found in 3D Printer Extruders


A very small extruder, ideal for multi-color or multi-material 3D-printers.
The design is derivated from the multi-material-extruder from RepRapPro.


The original design of this extruder comes from Adrian Bowyer (first seen on vimeo http://vimeo.com/54462325), I have just slightly modified it. The extruder body is modified to use a tongue to hold the bowden tube - so eMaker-Huxley and RepRapPro hot-ends should fit without problems (and without any adaptions). The second change to the original design is the screw hole for the idler (idler screw only can be removed, if the stepper motor is dismounted). And I have made a change to the grub hole in the small gear to make the nut retainer a little stronger. If you want to have a look to the original files please visit: github.com/reprappro/Mendel.

Update V2 (3 Feb 2013): assembly instruction added; V2-extruder-block added (moved filament-drive-axis 0.5mm for better fit of hobbed bolt; larger hole for idler screw); deeper hole for motor flange (better motor fitting if your printed bridges are not perfect).
Update (24 March 2013): OpenSCAD sources added (they are not really nice - but better than nothing)

Watch this extruder in action: YouTube ( http://www.youtube.com/user/3DAndyAustria ) - there you can find an assembly instruction video also.

Some pictures of the mounted extruder could be found on Flickr ( http://www.flickr.com/3d_andy ) - there you can see also the mounting kits for M8 or M6 threaded rods (and of course assembly pictures).

Needed parts to build one extruder-drive:

  • 1 of each: extruder-body.stl, small-gear.stl, large-gear.stl, tongue.stl
  • 1 M3x5 set screw
  • 1 M3x12 bolts
  • 2 M3x16 bolts
  • 2 M3x30 bolts
  • 4 M3 washers
  • 4 M3 nuts
  • 1 M3 nylock nut
  • 3 623ZZ bearings
  • 1 hobbed bolt (need one? Feel free to write a private message on thingiverse or an e-mail to 3d.andy(AT)gmx.net)

For mounting the extruder to the top of a Mendel/Prusa (with M8 rods) you will need:

  • 2 mendel-mount-front.stl
  • 1 mendel-mount-rear.stl
  • 3 M3 nuts
  • 1 M3x16 bolt
  • 2 M3x25 bolts

For mounting the extruder to M6 rods you will need:

  • 2 huxley-mount.stl
  • 2 M3 nuts
  • 2 M3x20 bolts

Good luck!

More from 3D Printer Extruders

view more

All Apps

Auto-magically prepare your 3D models for 3D printing. A cloud based 3D models Preparing and Healing solution for 3D Printing, MakePrintable provides features for model repairing, wall thickness...

App Info Launch App

Kiri:Moto is an integrated cloud-based slicer and tool-path generator for 3D Printing, CAM / CNC and Laser cutting. *** 3D printing mode provides model slicing and GCode output using built-in...

App Info Launch App
KiriMoto Thing App

With 3D Slash, you can edit 3d models like a stonecutter. A unique interface: as fun as a building game! The perfect tool for non-designers and children to create in 3D.

App Info Launch App

Print through a distributed network of 3D printing enthusiasts from across the US, at a fraction of the cost of the competitors. We want to change the world for the better through technology, an...

App Info Launch App

Quickly Scale, Mirror or Cut your 3D Models

App Info Launch App

Treatstock is an online platform that offers decentralized manufacturing services such as 3D printing and CNC machining for clients all over the world. We offer free and instant access to comparati...

App Info Launch App

3D print your favourite design with NinjaPrototype, a professional 3D manufacture with consistent quality and speed.

App Info Launch App

guys i need this extruder ( i have the original rpp) but i would like this for a nema17 stepper. I would really appreciate if someone could upload a nema17.

Maybe I still have the original stl-files for the Nema17 Extruder - drop a message to 3d.andy(AT)gmx.net and I will try to have a closer look to my old files ...

Nice design. Printing one now for testing. Any details on the "hobbed bolt" or where someone can purchase one? Dimensions of the hobbed bolt would be nice to add to the assembly manual...?

Hi, I think there should be a drawing of the hobbed insert somewhere in the Mendel-section of the reprappro github https://github.com/reprapprohttps://github.com/reprappro - my hobbed bolt has nearly the same dimensions (sorry can't find the drawing any more). If you would like to by one just take a look at my listings on emakershop http://www.emakershop.com/Seller=2273http://www.emakershop.com/Sell... - I have some more hobbed bolts for sale...

Anyone with a nema 17 version of this?

RepRapPro has a Nema17 version in use with the Mendel - should be available for download from their github-repository (https://github.com/reprappro/Extruder-drive/tree/master/Print-extruder-drive)https://github.com/reprappro/E....

Best wishes
3D Andy

Is this for 3mm filament? Is not, do you have a version for 3mm? Thanks a lot

Hi, sorry this extruder is designed for 1.75mm only - I don't know,if it is strong enough to handle 3mm filament :-(

Any particular instructions for printing this to get a nice usable finish?

No, not really. I printed my extruder drives with a 0.3mm nozzle and a layer height of 0.2mm. My parts work fine - without any special printing options or manual cleaning of the parts.

Hello, I've printed this (a few times now!) and I am finding that the gears don't quite mesh since they're a little too far apart. I'm wondering if I am loosing the ends of the gear teeth because I'm printing on a 0.5mm hot end. Should this be okay?

Hello, sorry for answering so late - I didn't see your comment (no e-mail from thingiverse?). I printed this extruder parts several times before and didn't have any problems with the gears. I use a 0.3mm nozzle, a layer hight of 0.2mm and PLA-filament. This print-setup works very fine.

I like it, but some notes about coding:

You know instead of making comments //This is thing you can just make a module and say translate(to_position) thing(); Also forcan save a dozen lines in some places. For instance where it says //XXX anders:

translate([0,-2.5,2.6/2]) for( y=[0,5,-5,10] )       /// XXX ANDERS!!!
    translate([0,y]) difference() {
        cube([20,3,2.6], center=true);       /// XXX ANDERS!!!
        cube([19.2,2,2.6], center=true);       /// XXX ANDERS!!!

That said, the code for the original you started from is far from perfect. (Not that i expect perfection :), neither are mine)

Oh, if happen to want it cleaned, I already have done it a bunch, I can post it somewhere if you wish. I want to make the E-motor easily removable and add the ability to configure it for the hobbled bolt. http://reprapworld.com/?products_details&products_id=353&cPath=1616_1651http://reprapworld.com/?produc...

Of course that'd lower the gear speed ratio, by about a factor two, if the servo is not ok with that.. hmm i have a problem. (maybe a need to start from scratch problem)

Thanks, if you wish I can publish your cleaned code here (I wrote you a PM).
The support thing is for the idler-bearing-hole (to create a nice rectangle to fit the idler bearing).

Thank you for posting this. The inner-toothed gear idea is fantastic, allowing for a higher gear ratio in a small space. I'm currently working on a NEMA 17 derivative.

ah thanks for having exported it ! I tried too but failed even with the missing library