With a second working 3d printer in the house, I needed an extra filament spindle box. It was easy enough to build the first one for my Makerbot, so why not build a second, improved one?
The most wanted improvement was a window.
It turns out, that it’s not only nice looking but sometimes also important to see what’s going on inside the box. So I changed the design slightly to sport a window on the front.
Since it turned out, that the second disk above the filament spool on the turntable isn’t really needed (the spindle’s construction is self-supporting and the box’s top keeps the filament on the spindle), I recycled the spare plywood disk in the second filament box: It got promoted to be the turntable. (If you don’t have an extra plywood disk at hand, see here how to cut the disk out of a rectangular sheet of plywood with a Dremel).
Needing even less wooden parts (no front side, no plywood for the turntable), the remaining material was even cheaper to get. Including the sheet of transparent plastic (“Hobby Glass”, a sheet of 2mm transparent LDPE, 25x50cm), the whole stuff cost me less than 5€ (!).
Here’s the updated part list for the box:
| Qty | Size (mm) | Material |
| 2 | 310 x 310 | MDF 10mm |
| 2 | 310 x 120 | MDF 10mm |
| 1 | 290 x 120 | MDF 10mm |
| 1 | 280 x 280 | Plywood 4mm |
| 1 | ~ 300 x 130 | Transparent plastic, acrylic, glass... |
There were some requests for detailed drawings, so here you go:
(These drawings are also available as PDF. I added them to thing 3640 on thingiverse.com.)
The change in design is, that -instead of a front wall- there’s a groove for a sheet of transparent plastic (or acrylic, or glass, or whatever).
If you got a circular saw, the grooves are quite easy to make: Adjust the circular saw blade’s height to about half the MDF thickness (i.e. if you use 10mm MDF, adjust the saw to 5mm). Then use the saw’s stop to saw the groove 10mm from the front side of the bottom, top, left and right parts (I hope I’ve got the technical terms about right in English…).
If you don’t have a circular saw at hand (I don’t!), you might use a Dremel to cut the grooves. That’s slightly more work and probably not as exact, but it’s good enough:
After cutting the grooves and drilling all holes, the assembly of the box is quite easy. I used some glue for additional stability.
Then I did measure the final width of the front window (including the depth of the grooves).
Cutting the LDPE sheet was very easy: After slightly slitting the sheet with a box cutter, the sheet can be broken at a table’s edge. It’s like cutting glass, only with a knife and without the cullets.
Now I was able to mark the final height of the window:
Another LDPE-cut later, the box was almost finished:
I didn’t change the inner construction of the box. So all printed parts, ball bearings and rods are the same as in the first box.
I added one last improvement to the box’s turntable: Since the filament roll tends to loosen up a little bit on the turntable, it can happen that some loose filament “falls” from the turntable. That’s usually not a big problem, but it could lead to a turntable-jam.
To avoid that, I used some paper (160g/m2) to build kind of a “cake setting ring” around the turntable (maybe one could actually use a real cake setting ring for this?).
The paper ring catches the loose filament windings, but it doesn’t interfere with the unwinding mechanism itself.
