Wall Mount Spool Holder with Bearings (Customizable)

A wall mount for spools that use the bearings and aluminum tubes from the MMU tray it replaced.

I came up with this Wall Mount for Prusa Multiple Materials 2S Filament Buffer solution because I couldn't fit five Prusa Trays on my desk behind the printer.

I needed pegs for the wall mount solution and wasn't happy with solid pegs so I figured out how to incorporate an axel from the trays into a wall mounted peg. It works great!

In response to a couple of comments I revisited this effort and created a customization macro for FreeCAD. For more information on how to create a customized bearing peg scroll to the bottom of Print Instructions.

• Single mount hole:

  • 'I' design elegant but tricky to mount
    
  • 'L' design is easy to mount
    

• Two mount holes:

  • 'Slim' design, minimal side tabs.
    
  • 'Sturdy' design, extended height side tabs.
    

• 'V4', the first design with very wide tabs because it was made to replace solid pegs that were already mounted.
  

• The design is minimalist so it prints much quicker than most wall mounted pegs.

• I made it possible to change the location of the bearings so one design covers all of my filament spools, even the ones too small for the Prusa trays.

• FreeCAD files can now be posted so I have included it here.

Print instructions

Files

• bearingpeg_75_40 = 'Slim'

• bearingpeg_75_40_10 = 'Sturdy'

• bearingpeg_oneholetop_75 = 'I'

• bearingpeg_oneholecenter_75 = 'L'

• bearingpegv4 = First design, very wide tabs

• bearingpeg_heavyduty = For 2.5 kg spools

Printer Settings -> Original Prusa MK3S

Print Settings -> 0.20mm - Speed MK3
Perimeters: 3
Solid layers - Top: 5 Bottom 4
Fill density: 15%
Fill pattern: Gyroid
Rafts: No
Supports: No
Filament Type -> Generic PET

Parts

You will need the following parts (or their equivalent) from the Prusa Filament Trays.

• 10x 608 Bearings
• 5x 8*120mm Aluminum Tubes

Here are links to parts as examples.

300mm 8mm Aluminum tubing - x3 = Cut your own

608 Bearings

Assembly

Select which slot to use for the outer bearing. The second one is good for 75mm spools.

• Push 608 bearing into wall mount but not all the way to the bottom.

• Optional: Slide two of the rubber grommets onto the axle. These have to be positioned to ride evenly on the inside hub or the spool may tilt a bit. Works fine without these.

• Slide the other bearing onto the 120mm tube

• Position the tube so it can be inserted into the wall mount bearing with the outer bearing positioned above its slot.

• Push the tube into the bearing until it clears the outside edge and can be pushed into place.

• Push on the rod near both bearings to press them into their place.

• Verify the axle turns freely.
  

Source File

FreeCAD: BearingPegV4_2019.FCSTD

Reinforced

Within the pegs (excluding the original V4) 'pins' are embedded that promotes a strong cross pattern with lines at the stress point in addition to beveling.

For a 0.20mm print:

• 5.0mm = Start of cross pattern
  
• 6.0mm = Long Lines
  
• 6.4mm = Long Lines cap
  
• 7.0mm = End of cross pattern
  

This is 2.0mm of reinforcement.

Customization

Download and install FreeCAD and load the 'bearingpegV2.fcstd' file.

• Click on the 'Settings' to view,
• Window - Tile to see both settings and model

Change settings (and click out of the changed cell) and instantly see what changes. Here is a video that demonstrates how to use this macro.