Filament Buffer for 350mm Vorons

Inspired by the remix from Drakka01, completely rebuilt using the parts from Karkovski.

I was having trouble with finding a buffer for my 350mm Voron V2.4r2 that was large enough to deal with the over 100cm of filament. I wanted something reliable, added as little resistance to the filament path as possible and took up as little room as possible. There are quite a few other very good and popular buffers out there but I always had issues with one of those requirements until I tried the remix posted by Drakka01.

Unfortunately that remix has quite a few small issues I did not like and found troublesome when building a larger array. I ended up correcting all of these issues myself using the files from Karkovski's post with Drakka01's version as a guide. This can be installed on any side of the 350mm BOM built Voron 2 and Voron Trident.

(Warning! Some Voron kits have a taller Z axis, this will not fit as is for those.)

Overall Redesign

I removed the need for supports for any part I modified following the design philosophy of the Voron Team. All M3 holes facing the bed have built in bridges, no need for supports or cleaning holes when done. The ECAS hole is shaped to deal with the drooping filament at the top but I could not properly reshape the filament hole by remixing the STL file of the original, you may still need to clear this hole during assembly.

I tried to keep all fasteners to what would be found in the Voron V2 BOM as most will have these available or able to readily source more after their printer build.

All hex nuts were removed in favor of the Voron spec M3 heatset inserts. This allows the holes to be closer together and leave more material in the part for strength.

The single large M5 hole for mounting was too cumbersome when stacking four units together. It required a nearly impossible to find length bolt and using threaded rod was even more difficult. The bottom set of holes also kept binding on the longer screw and making the whole install process a nightmare. This was changed to shorter M3 screws that will secure a single buffer to the one under it, modularly stacking them all together without needing a large screw.

Base

Rebuilt for better fitment of ECAS fittings, I found the other versions were too tight and split too easily.

The heatsets can be installed from either side, I recommend from the top (side away from the print surface) to allow for shorter fasteners.

Slide

Added the corresponding holes for the Base.

Built the Panel Brace pieces directly into the slide to help reduce the part count.

Panels

Resized for a more uniform assembly, the front and back now have matching thicknesses and top and bottom lengths. This leads to a better look, reduces bowing and adds strength.

A pin was added between the top and bottom halves for strength and better alignment.

New Parts

I created a piece that will bolt to the frame that'll stay in place for installing the buffers.

A new spacer for the bottom mounting hole used between each buffer.

Required Hardware

Buffer Assembly (each):

• Slide to Base (Heatsets installed from Top): 4x M3 x 8mm SHCS OR Slide to Base (Heatsets installed from Bottom): 4x  M3 x 20 SHCS
• Buffer Panels: 6x M3 x 12mm SHCS
• Roller Assembly to Panel Assembly: 4x M3 x 16mm SHCS
• PTFE Fittings: 2x ECAS04
• Heatset Inserts: 18x M3 x 5 OD x 4 L (Includes 4x for buffer to buffer mounting)
• Roller Bearing: 605 (5mm ID x 14mm OD x 5mm Thick)
• Bearing Fastener: M5 x 12mm (MINIMUM! Original was 12mm, I found this too short. I recommend 14 or 16mm)

Mounting:

• Standoff to Frame: 4x M3 x 12mm SHCS, M3 T-Nut, M3 Heatset 
• Buffer to Standoff - Top: 2x  M3 x 25 to 30mm SHCS
• Buffer to Standoff - Bottom: 2x  M3 x 16 to 20mm SHCS
• Buffer to Buffer - Top: 2x M3 x 30 to 40mm SHCS (40mm for Heatsets from Bottom)
• Buffer to Buffer - Bottom: 2x M3 x 35 to 40mm SHCS

(Minimum to maximum, most holes are through holes and allow for longer screws)

Print Settings:

I printed mine in SuperSlicer with the following settings, PrusaSlicer may differ.

0.2mm layer height

24 perimeters (gets rid of infill between perimeters on 0.4mm lines)

0 top and bottom layers

110% first layer width (gets rid of the first layer coming too far into the first layer infill)

150% infill width (to strengthen it)

10% Honeycomb infill pattern.

Assembly:

Similar to the other models with one key difference. The two M3 holes that replaced the M5 will need staggered inserts. As an example if you are stacking three buffer assembles you will need one to have 4 insert in the top holes, another in the bottom holes and the outer most buffer does not need any. For my set up of 8 buffers I kept it simple and installed 4 with top inserts and 4 with bottom, I can mix them as needed. (I will take a better picture of this shortly)

To-Do:

• Redesign the spacer between buffers to be easier to handle
• Design a new frame mount for easier removal of the entire buffer stack
• Redesign the bearing retainer to remove the need for supports
• Add “Load” to both sides of the slide
• Design slide caps for filament labeling

Changes:

2023-03-19: Added CAD of the files I edited per request.