The revised X-Axis is fully compatible with stock Prusa frame (MK2/MK3), as well as with the Haribo/Zaribo/Bear frames.
The compatibility with different extruders comes from the X-carriages provided in this listing, stock ones will NOT work, unless explicitly stated otherwise in the compatibility list below / please check the compatible X-carriages in the description.
The design is intended as an upgrade to the stock one Prusa Research provides, adding features like:
Belt tensioner - A simple and sturdy system for fine adjusting the belt tension on the X axis while keeping the correct belt path. Replaces the stock design of rotating the X-motor which stresses the X-end printed part, in some cases, to the point of breaking.
Belt tensioner "puck" customization - Allows the use of different hardware (idlers) with the existing printed parts (whichever option you went with). You can pick the corresponding tensioner (puck) with the idler you have available, and even switch later on just by printing another version of the puck without the need of changing anything else in the system. The tensioner pucks are interchangeable.
Bearing clamps - Allows a lot more easier assembly of the X-ends, replacing the stock pressure fit design which can be inconsistent with different materials/printer settings. The clamps additionally allow some pre-tension on the bearings, but please do it with caution as you can cause the bearings to bind.
- Unified and customizable system, compatible with plenty of available extruders for the I3 and the clones alike (*with compatible X-carriages included in this listing, stock ones will NOT work, unless explicitly stated otherwise in the compatibility list below / please check the compatible X-carriages in the description).
Each feature of the 3D models was carefully checked and fine tuned. Optimized for FDM 0.2mm layer height printing, making sure the parts are accurate and easy to print.
For detailed instructions on how to fine tune your X-axis while assembling, please check out Bear Upgrade excellent guide here
STEP files are included for your modding pleasure and convenience. STL files were sliced and checked with Slic3r PE. Any constructive feedback is welcomed.
0.2mm (highly recommended)
I printed the parts from PETG, 0.4mm nozzle, 3 perimeters, 30% infill, 5 top/bottom layer which works quite fine for my prints. That being said, the model isn't strictly tied to those settings, feel free to adjust them to your liking.
I would say it safe to stay within these limits:
5-7 bottom/top layers
Perimeters affect the strength of the parts the most, but also add weight the most. I would balance the amount of infill according to how many perimeters you choose. The number of bottom and top layers shouldn't be much of a factor for most of the printed parts, and its safe to use 5 regardless of infill/perimeters.
One of the goals of this project was to unify under one system all the different X ends I have published, without the optional parts causing a cascade of changes within the system, warranting reprinting of compatible parts.
Each part is fully compatible with any of the other versions of the files posted in this listing (unless explicitly stated otherwise). You can cherry pick which version you want, without the worry of checking for compatibility with the other parts.
Please note that the belt path has changed with this version, so any previous versions of the X-Ends I have published will be not be compatible with this system
Another goal was to make the X-axis compatible with as many different extruders possible, with the X-carriage being the only part that changes in the system, while still keeping the flexibility of using whichever setup of the X-axis (optional parts) you end up using.
MK3 - Link
X-Motor compatible with MK3
- MK2.5 - Link
X-Motor compatible with MK2/MK2.5
- Adjustable X-Idler - Link
Uses screws to adjust the X-idler positioning (+/- 0.5mm).
Although this design has its own benefits, it might be finicky to set up properly and for relatively new users I'd recommend the "stock-like" version.
- Stock-like X-Idler - Link
Removes the two screws from the adjustable version, matching the design of the stock MK3 X-idler.
- for 16T or smooth equivalent - Generic 2GT 3mm ID - Link
-Idler sourced from Zaribo, or other 2GT idler suppliers available near you. Make sure the idler is with dual bearings, and ideally from a source that has reliable product quality.
-Compatible shaft is Ø2.9-2.99mm, 15-16mm in length. I used a gage pin and cut to size.
Also, you can cut a partially threaded M3 screw to extract the non threaded part.
The intention with the idler puck was to constrain the possible lateral motion of the idler pulley and I have tested it with my prints, however some prints might not turn out as precise as designed. In case the idler pulley doesn't fit the tensioner puck (width) there are corresponding versions with looser tolerances (more clearance) found in this zip file.
Please note if you go the gage pin route, that the 2.99mm or 4.99mm ones (depending on idler version) are quite the snug fit with the idler's bearings. Although I don't expect it to be a problem (it rotates just fine, but it does have very slight tension), you might want to consider ordering a bit smaller diameter ones (maybe 2.97-2.98mm / 4.97-4.98mm)
The tensioner puck now has a bit more room to work with and adjust to slightly different idler pulleys. Please feel free to contact me if none of the tensioner pucks fits your current hardware, I should be able to make a compatible version, or even better, if you make one I will make sure to add it to this list.
X-carriages compatible with the Revised X-axis
Please follow the link to download the files for the compatible X-carriages
These X-Ends are ONLY compatible with the X-carriages linked below. Stock carriages will NOT be compatible unless clearly stated otherwise
Bondtech Prusa Extruder
Prusa Stock Extruder
- Bear extruder - directly compatible*
*If you plan on using a 16T idler, the belt will have very small clearance with the carriage and it might be an issue. A small edit of the carriage should fix that, and its in the queue.
The compatible carriages list is work in progress. Carriages for different extruders or extruder versions are planned. Please message me if you have a specific extruder carriage that is not on the list, I will see what I can do. If you like to make your own compatible carriage with these X-ends, feel free to contact me, I will add it to this list.
The holes for the smooth rods must be slightly expanded by drilling with a 8mm drill bit until the smooth rods can be easily inserted. Considering the small amount of material that is removed, you can do the process by hand (gloves help a lot), but in case you use a power tool, make sure you use short bursts/low RPM to do the drilling.
Reason for this post processing is because, in addition to the print orientation issue, designing the tolerances for the smooth rods holes for each different print material, printer settings (etc) in one version, is impractical and leads to inconsistent results. Lightly drilling off the excess material ensures the smooth rods fit properly regardless of the print material and any possible printing artifacts (stringing, blobs etc).
The smooth rods should be a snug fit with the X-ends, do not over do it with the drilling. I suggest using the drill only if the rods need excessive force to be inserted into the X-ends
Slightly expand the holes with an 8mm drill bit on both X-ends.
Depending on the severity of the elephant's foot on the tensioner puck, some scraping might be needed to ensure proper fit.
Scrape off the elephant's foot if its too severe.
The hole for the idler shaft is designed with 2.9-2.99mm (4.9-4.99mm) tolerances in mind. Depending on which route you take (diameter), you might want to very lightly drill the hole with a 3mm (5mm) drill bit IF the pin is hard to insert.
Lightly drill the hole if you end up using a shaft with tight tolerances (~2.99/4.99mm). Only if you have problems inserting it into the tensioner puck
Before applying any tension to the belt, make sure the tensioner puck is level or slightly protruding outside (~1mm) of the X-Idler. The end position of the tensioner puck (desired belt tension) should always be inside the X-idler, to allow the full intended length of the X-axis (even more important for MK3 users).
I case you end up with the desired belt tension but the tensioner puck is still protruding outside, don't try to insert the tensioner puck inside the X-Idler at the cost of adding extra tension to the belt, instead, remove the belt from the X-Carriage and re-seat it a bit closer to the X-Idler.
-(16/04/2019) I mistakenly uploaded some older versions of the X-motor (both versions). Replaced them with the new ones, if you already downloaded the older files, it might be worth downloading them again. That being said, the only change is the slightly more belt clearance, so you wont have problem even with the older file.
-(17/04/2019) Added MK2.5 compatible X-carriage for the Bondtech Prusa Extruder
-(14/05/2019) Added versions of the tensioner pucks with looser tolerances for the idler pulley (width).
-(26/05/2019) Edited the MK2.5 X-Motor so the M2x12mm bolts aren't so difficult to insert. Increased the diameter of the holes and added a bit more depth for clearance.
In no particular order I would like to mention the sources of the designs I got inspired from, or people who helped me in one way or another with the design. Thank you all.