Nubby - Hybrid A1 Nozzle Wiper for X1/P1

Latest Update - March 29, 2025

Latest Model Version - v1.11 (February 4, 2025) - Scroll to bottom for changelog

What is Nubby?

Nubby is a modification that adds an A1 wiper pad to augment the stock X1 / P1 wiping system.  This modification addresses the issue of residual material that is often left on the print nozzle by the stock wiping system.  

Nubby is easy to print, and installs in seconds without additional hardware.  Unlike most other A1-style modifications, Nubby allows for the stock wiper to remain in its stock position and function normally, and retains normal printhead parking, LiDAR and first-layer scan functionality without the need for hardware or G-code modifications.

Nubby is designed for use with the standard A1 wiper.  It is not compatible with A1 mini wipers.

Supplies

• Bambu A1 wiper - these come in packs of three, and since you are trimming 3x3 pieces, this will give you enough to make 12 
  • Heatbed Nozzle Wiper - A1 | Bambu Lab CA Store
     
• Sharp blade or scissors - used to cut the A1 wiper to size
   
• Cyanoacrylate ('super') glue
  • Anything will work, but I prefer using a gel formulation as it is easier to work with - I use Loctite Super Glue Ultra Gel Control
     

Printing

Nubby prints in around 15 minutes, and uses around 1g of filament (including supports).  The supports remove easily either by hand or with a small pair of pliers.

I recommend a filament that has reasonable heat tolerance due to the proximity of the print nozzle to the mount.  PETG would be a minimum, and I prefer using ASA.  Print profiles have been provided for:

• PETG
• PETG with PLA interface for easy support removal
  • Check your flushing volumes before printing - Bambu Studio will occasionally override the profile's flushing values and you may get layer adhesion issues (especially where the base meets the A1 wiper mount).  You should use the following flushing values:
    • PETG → PLA - 400

    • PLA → PETG - 800

      
      How to check / adjust your flushing volumes in Bambu Studio / Orca Slicer

      

       

• ASA / ABS

  • Please note that the provided ASA / ABS profile is scaled at 100% - this worked well for Polymaker ASA, but you may need to adjust the scaling or filament shrinkage value based on the behaviour of your specific filament.  Consider using the Nubby Sizer to properly determine your scaling value (see the Troubleshooting section for details regarding this).

     

Installation

1) Cut a 3x3 square of A1 wiper, and remove the backing exposing the adhesive.

2) Place a small drop of superglue / CA glue onto the wiper mount surface - make sure to not put too much as it will squish out.

3) Place the A1 wiper onto the mount surface - the wiper is properly aligned by pushing it towards the bottom right corner as indicated.  The wiper should sit square and flush with the entire mount (except the bottom right cutout).
 

4) Nubby should fit snugly on the bottom right corner of the purge chute (looking at the printer from above) - it should be virtually self aligning in the proper spot.
 

5) Press down on Nubby until it stops.  You're done!
 

Troubleshooting

Nubby fits too loose / too tight → use the Nubby Sizer to scale your base

Some users have reported that Nubby fits too loosely, causing it to get knocked loose.  There is variation in manufacturing tolerances of the purge chute, and/or due to variation in filament shrinkage.  To help address this, I've created a set of Nubby sizers (look for ‘Nubby Sizer’ under print profiles). 

The Nubby Sizer file will print a set of small chips that contain a number as well as a section of the Nubby mount.  The number indicates the scaling factor, and the mount attached to the chip is scaled by that specific factor.  Print the sizers using the same filament as what you want to print your final Nubby with.  The sizers are designed so that they print quickly without supports, and can be fit directly onto the corner of the chute for sizing.  You can either print the full set of sizers, or just select the ones that you want to try.  You can also adjust customize the sizers further by adjusting the scaling values of the ‘Corner Bracket’ object.  The base width between the mounting legs is 2.0mm, so a 2.5% increment will give you around 0.05 mm change in the mount size.

• Nubby mount is too loose → use scaling values <100%
• Nubby mount is too tight → use scaling values >100%

Once you have figured out the appropriate fit, you can adjust the Nubby model in your slicer to reflect the best fit.  To do so, please see the following images.  I recommend only changing X-Y scaling, and not Z scaling.

Step 1: Select ‘Objects’ under the Process menu (left hand side of the slicer)

Step 2: Select the ‘Corner Bracket’ object - make sure it is highlighted

Step 3: Click on the ‘Scale’ tool (shortcut key ‘S’)

Step 4: Make sure ‘uniform scale’ is unchecked, and then input the appropriate scaling size (based on your sizers) into the X and Y scale boxes

Nubby v1.0/v1.01 is interfering with the build plate tab / Z-axis homing → use Nubby v1.11

Public testing of the original Nubby revealed issues with the original mounting solution.  There is sufficient assembly variance in the mounting position of the heat bed which can result in extremely narrow clearance between the back of the heat bed and the purge chute.  This resulted in homing issues as well as the heatbed running into Nubby when the bed was raised.  

With the release of Nubby v1.1, the mount has been significantly revised such that the incidence of interference between the heat bed and chute should be significantly reduced, if not completely eliminated.  Previously, Nubby v1.01a (aka Stubby Nubby) existed to try to address this issue, but with the release of v1.1, there is no longer any need for Stubby Nubby, and thus the model has been depreciated.

Design Philosophy

BACKGROUND

While many of the existing X1 / P1 wiper modifications work well for reducing filament build up on the nozzle, I found that existing solutions did not fully meet my use case or wishlist for features.

Nubby was designed with the following in mind:

• The modification should augment, not replace the stock X1 / P1 wiper system.  
  • The stock wiper works well for bulk removal of material, as well as longer filament strands with its ‘flinging’ action.
  • The A1 wiper works well for removal of residual material from the nozzle as it provides a ‘wiping’ / ‘scrubbing’ action.
     
• The modification should retain stock behaviour and functionality of the X1 / P1 printer
  • Many users simply want the wiper to work better without changing the overall functionality of their printer
  • Users may not be comfortable or familiar with modifying G-code.
     
• Existing solutions integrating A1 wipers with the stock X1 / P1 system can interfere with filament purging or LiDAR scanning functionality.  
  • To allow for mounting of the A1 wiper, some designs will modify the position of the stock X1 wiper (either pushing it into a different position with a modified mount, or flipping the mounting direction of the stock wiper).  However, changing the position of the stock wiper can cause the following issues:
    • The nozzle can crash into the stock wiper if First Layer Inspection remains enabled, and can cause damage to either the wiper and/or printhead.
    • The printer may purge onto the wiper mount, causing purge material to not properly eject into the purge chute.  This can cause abnormal buildup of material in the chute and potentially lead to clogs / jams.
  • Wiper designs that cover a portion of the purge chute can result in purged filament jamming in the chute, or being deflected into other parts of the printer, and at worst, onto the build plate.
     
• The modification should be easy to install, but not compromise functionality or durability.
  • The screw hole for the wiper mount in the purge chute is plastic, and has a reputation for stripping out with repeated assembly / disassembly, or from overtightening of the mounting screw. 
  • Some wiper modifications utilize a bracket that secures to the printer using mounting screws located on either side of the purge chute.  However simple, users may not want to or have the ability to remove and replace mounting screws in their printer.
  • Wiper modifications that shift the location of the stock wiper, or flip the stock wiper often do not allow for sufficient deflection of the flinger arm, or alter the mounting height of the wiper.  This can cause issues with either premature wear / damage to the stock wiper, or premature wear / damage to the print nozzle.

HOW DOES NUBBY SET ITSELF APART?

1) Virtually eliminates the issue of residual filament / poop on the nozzle after wiping

Importantly, Nubby does exactly what it sets out to do, which is to virtually eliminate all issues with retained filament on the nozzle tip.  The reason I do not say always is that I cannot be certain there aren't some edge cases where there may be a small amount of residual poop on the nozzle; with this said, over the course of testing, Nubby has completely eliminated print issues caused by residual filament on the nozzle tip, especially with traditionally ‘sticky' filaments like PETG and TPU.  There can occasionally be a few strands of filament retained on the A1 wiper itself, but these do not stick to the nozzle and often self-clear on the next wiping cycle.  

2) Allows all stock functions of the printer to function normally

Nubby does not interfere with First Layer Inspection, LiDAR scanning, or stock wiping / purge behaviour.  It works without any G-code modifications. Since Nubby does not modify the location of the stock X1 / P1 wiper, it should not cause any premature wear to the stock wiper or print nozzle.  The height of the A1 wiper mount has been carefully designed to maximize wiping of the nozzle surface while ensuring that it does not sit too high to cause excessive stress on the nozzle, or cause excessive / early wear to the A1 wiper.  

Nubby is also designed to provide clearance for the build plate tab, and does not cause issues with Z axis homing.  While not tested, there should be sufficient clearance for third-party build plates provided the dimensions do not radically differ from Bambu plates.  At this time, the following build plates have been tested for use with Nubby:

• Bambu Textured PEI Plate | Bambu Lab CA Store
   

Nubby allows for proper printhead parking during First Layer Inspection

Nubby allows for proper build plate tab clearance

3) Prints quickly and easily, and installs quickly and securely without any additional hardware or tools

Nubby prints in around 15 minutes, and uses around 1g of filament (including supports).  Nubby is self-aligning and installs in seconds without need for additional tools or hardware.

Changelog

March 29, 2025

• Minor edits and revisions to text content.

March 25, 2025

• Nubby v1.11 has now been released for long enough, and with enough positive feedback that I feel comfortable depreciating older versions (v1.1 and v1.01) to avoid issues with users printing older versions.  There should be virtually no use cases where older versions would provide an advantage over the most recent v1.11.
  • v1.0 and v1.1 can still be downloaded (under ‘Download STL/CAD Files’), but the profiles will be hidden.

February 4, 2025

• Nubby v1.11 model and profiles published
  • This model will supercede the v1.1 profiles as based on initial testing, there is a straight improvement across the board in terms of fitment and print performance without compromising functionality.
    • The v1.1 3mf can still be accessed in the STL/CAD repository but will no longer show on the print profiles page.
  • Changes:
    • The geometry of the mounting bracket has been cleaned up and should reflect the contour of the purge chute more accurately.  Practically speaking, this means that the mounting solution should ultimately be more stable and secure in the long run. 
    • The geometry of the wiper mount relative to the base has been refined.  
      • This has also had the effect of simplifying the printing orientation, which makes supports substantially simpler to print and remove.
      • This change has slightly decreased filament usage and print times in the ASA and PETG profiles by around 1-5%.
      • This change has substantially decreased filament usage and print times in the PETG w/ PLA support profile by 50%.
    • The height geometry of the wiper base has been slightly adjusted to reflect the change in the mounting geometry to maintain nozzle wiping performance.
    • All print profiles have been updated to use snug grid supports.
      • Testing has shown that snug grid supports outperformed organic supports for this model in terms of filament usage, print time, and ease of removal.
      • PETG top support offset increased from the default 0.2mm to 0.25mm to improve ease of support removal.
• Nubby Sizer for v1.11 published
  • The mount geometry for Nubby v1.11 is slightly different to v1.1, so a new set of Nubby Sizers was created to reflect the updated mount.
  • For the same reasons as previously mentioned, the v1.11 sizers will supercede the v1.1 sizers in print profiles, but the v1.1 sizers will remain accessible as a 3mf download.
• STL/CAD Download Repository updated
  • 3mf of current version of Nubby and Nubby Sizers is available in the root folder.
  • Older versions of Nubby and Nubby Sizers are available in a ‘Old Versions’ subfolder.

January 18, 2025

• Minor content edits

January 11, 2025

• Corrected an issue with the v1.1 PETG profile.
  • Between testing and uploading the profile, the top Z distance and interface spacing was erroneously set to 0, causing unnecessarily difficult removal of supports and scarring.
  • Top Z interface and interface spacing has now been reset to Bambu Studio defaults.

January 10, 2025

• All Nubby v1.1 profiles updated.
  • No geometry changes.
  • In the process of revising the CAD file from 1.0→1.1, I actually partially broke the ability to independently scale the bracket (leg) portion.  While scaling to <100% worked fine, scaling >100% was not working correctly.  Fortunately, I have found that most users are scaling down, which means that this ‘bug’ should have affected very few users.  This is now fixed.

January 9, 2025

• Cover photo and model name updated for clarity.
• Revised Troubleshooting section on scaling to be clearer on how to adjust scaling for too loose / too tight mount fitment.
• Nubby v1.1 sizers revised
  • The model itself has not changed, but the chips now differ by 4% scaling increments instead of 2%.  4% increments result in just under 0.1mm of size change, which makes more sense, and users can opt to scale models by 2% if they feel like they are ‘between sizes’.
  • New sizers offer scaling values of 108%, 104%, 100%, 96%, 92% , and 90%.  This should accommodate users where the 100% scale prints a Nubby that is too tight (and thus >100% scaling is needed). 

January 8, 2025

• Nubby v1.1 model and profiles published
  • Thank you to @jweaver999 and @andwtn for their invaluable feedback that guided these revisions.
  • Nubby v1.1 represents a significant revision of the original Nubby design.  
  • Raw model has been rebuilt to clean up the workflow, which allows future revisions and changes to be made more easily.
  • Changes:

    • Significantly shortened mounting solution without compromising stability or self-aligning feature.  This change should virtually eliminate issues with heatbed clearance.  When Nubby v1.0 was published, it became apparent that there was manufacturing variance in the heatbed position, with some users having extremely narrow clearance between the bed and the purge chute.  This led to homing errors / Nubby being knocked loose for a small number of users.  The revised mount avoids placing anything between the heatbed and the purge chute, and should address this issue. 
       

      

       

    • Model modified to appropriately chamfer / fillet edges to avoid stress risers between elements of the model, especially between the mounting bracket and wiper holder.
       

      

       

    • Height of the wiper mount was raised slightly in order to increase the surface area of the nozzle cleaned by the A1 wiper.  
       

      

       

• Nubby Sizer for v1.1 published
  • The mount for Nubby v1.1 is different, so a new set of Nubby Sizers was created to reflect the altered mount.
• Nubby 1.0 and 1.01 profiles updated
  • These changes mitigate issues that users had with the legs breaking while removing supports or mounting Nubby.  
  • Changes:
    • Default orientation of the model in the provided profiles is changed to alter the Z-axis of the print.
    • Supports changed from snug grid to organic (trees) - less filament used, quicker to print, and much easier to remove.
• Stubby Nubby (v1.01a) profiles removed
  • There is no longer any reason to use Stubby Nubby (v1.01a) with the release of Nubby v1.1.  To simplify the print profiles available, and avoid confusion, I have elected to completely remove the Stubby Nubby profiles.
• MakerWorld cover photo updated to better reflect Nubby features as well as the appearance of Nubby v1.1.

January 6, 2025

• Formatting changes
  • Troubleshooting subheading created - this cleans up the Printing section and should make reference easier
• Correction to incorrect subheading titles
• Changed the recommended alternative print orientation - this change in orientation retains the strength advantage of the altered z-axis but saves a bit of filament and printing time, and also should make support removal slightly easier

January 4, 2025

• Nubby sizer model and profiles published.
• Additions to printing section for troubleshooting a loose Nubby fit.

January 1, 2025

• Added version nomenclature to files and print profiles.
• Revisions to model page for clarity.
• Additions to printing section regarding model orientation for printing.
• Additions to printing section regarding the ‘Stubby Nubby’ model variant.
• Clarifications made on print profiles for PETG w/ PLA supports as Bambu Studio will sometimes change the profile's flushing values and cause issues with layer adhesion.
• V1.00 profiles updated.
  • PETG and PETG/PLA print profiles were incorrectly set to 2 walls while the description stated 3 walls.  Profiles corrected in Bambu Studio to correctly print with 3 walls.
• Nubby v1.01 model and profiles published
  • Changes – 
    • Further chamfered the base mounting portion to increase clearance for stock wiper deflection to reduce the likelihood of interference and excessive noise. 
    • Altered the angle of chamfer to the leading (left) edge of the A1 wiper mount base to increase clearance for stock wiper deflection.

    • Shortened the left front side of the base mount (looking from the top of the printer) by 1mm to provide additional clearance for the stock wiper deflection.  On testing this does not change the ability for Nubby to self-align

      
      
       

  • Notes:
    • Thank you to @RedRover for the feedback that prompted these adjustments.
    • It is unlikely that I will be able to modify the model to add any further clearance for the stock wiper deflection as it will compromise the strength of the model and affect the self-aligning nature / stability of Nubby.  Shortening or further chamfering the A1 wiper mounting base will be unlikely to provide further benefit as we are limited by the length of the 3x3 section of A1 wiper.  Nevertheless, please let me know if you have any issues and I will see what can be done.
• Nubby v1.01a ('Stubby Nubby') model and profiles published
  • Based off of Nubby v1.01.
  • Designed for a user who has manufacturing variance in their printer that results in extremely narrow clearance between the heatbed and front of the poop chute.
    • Significantly shortens the mounting base avoiding interference with the back portion of the build plate with the front of the poop chute.
    • Uncertain if this will affect long term stability of the mount, so I would still recommend most users print the standard Nubby unless you are running into build plate clearance issues.
       

December 30, 2024

• Clarified amount of filament used in PETG w/ PLA support profile.
   

December 28, 2024

• Initial design published (v1.00).