REMIX: The Shark Filament Buffer and Drybox System (V6) in plywood box

The Buffer and filament holder

This is a remix of Martin_au's filament boxes and buffer. I decided that I would like to make them in a plywood box with front facing door through which you can see the filament rolls. It is not that air tight as his design but it works for my space layout and for me the humidity is not that bad. You can still add silica boxes inside and will keep the humidity pretty low. The modifications that I have done are:

• the buffer shape is changed and now slots in the plywood box.

• the base of the buffer has two holes for 4M heat inserts which are used with 2xM4 8mm bolts to connect to the baseframe_holding_bracket. You will need 14 of those as I use one extra spooler for wall\holder.

• modified the buffer base to use M10 pneumatic fittings. The original is great, but used the original Prusa filings for the 4mm PTFE tube, and they are hard to find and cost around $5 AUD. I need at least 14 buffers and that is 28 fittings. So I decided to modify it. If you plan to stack the buffers next to each other without spool holder in the middle - it will not work with this remix.

• the lever is extended with just a bit longer handle, I found the original is a bit short for me and is harder to use

• pulley-8mm-bearing is modified a bit - created a deeper channel for the filament. Not sure if that helps but the original Prusa buffer is like that.

• the spool holder base now is much smaller and lighter, the bed for the M10 pneumatic fitting(pass through) is now under 60 degree angle the original was with 45 degree angle and was bending the filament when was passing through

• when the buffer slots in the plywood channel it has a small gap at the back. I decided just to add baseframe_end_caps which holds in place when you screw the base. Technically I could of just added them to the baseframe part, but as I realised it later it didn't bother to edit it.

• acrylic door hinges are extended and they use 3mm heat inserts and 30mm M3 bolts

• Magnet holders use 3x6mm round magnets

• acrylic door Magnet_holder uses 3mm heat inserts and are screwed to the acrylic door with 2x6mm M3 bolt. Magnets are glued in the holder with CA glue, make sure the magnets alleging on both sides with the correct polarity.

• The magnets holders attached to the box are screwed with wood screws. Make sure you use short and small wood screws. The magnets on the box side are installed after the doors are attached to the box with the hinges and the magnets are installed on the acrylic door. Then close the door put on the inside the box magnet holder and screw it to the box in a such way they are aligned. This is done before the buffers are installed in the box, it is easier to screw the holders to the wooden box frame.

Update 03 Nov 2026:

• I have added the combined STLs for the baseframe parts baseframe_both_3mm-pin_short_v2.stl, baseframe_left_3mm-pin_short_v2.stl and baseframe_right_3mm-pin_short_v2.stl. It combines the baseframe with the end cap - baseframe_end_caps.stl so they can be printed together if you like.

The Plywood box

I made 3 variants for the plywood box:

• all side panels  made from 10mm or 9mm plywood

• all side panels made from 12mm plywood

• a mix where the back and the side panels are 12mm plywood and the rest are made from 10 or 9mm plywood panels

The size written in the SVG file name is the size of the internal dimensions of the box. So depending the plywood used the external size will be from +20mm to +25mm larger on each axis.

Once cut the panels have to be cleaned (vacuumed from dust) and glued with strong wood glue. I used Gorilla Wood Glue and very small\thin nails to hold it in place. After it dried the glue in a day, sanded to box from outside to make the joints smooth and painted the plywood with sealer. Then I waited to dry well for a day and painted it. Painting is not required but I like it to be more colourful :). 

The external box corners are not required. I added them and they are glued no screws.

There are SVG files uploaded and you will need laser cutter to do them. Also the front panels are made from 3mm acrylic panels and I have made the door holding magnets brackets (acrylic_door_Magnet_holder, box_top_door_Magnet_holder, box_bottom_door_Magnet_holder). They use 3x6mm round magnets and for both doors you will need 16 magnets in total.

As I do not have CO2 laser cutter and mine is diode laser cutter, I have done doors in two parts:

• front door part in 3mm black acrylic

• internal clear door screen which is glued with super glue on the internal side. I cut this manually as a rectangle with some overlap of around 10mm.

If you have a CO2 laser cutter you can just cut the whole thing in clear acrylic without the middle window.

Just be carful when you are importing the SVG into your laser cutter app. I use xTool Studio and noticed that depending on from each app I edited the SVG I got different results. As a reference the size written in the object has to match the object size, if that is not the case something has been scaled and you have to select the object and scale it to the correct size.