Shelf-mount hanging spool holder by Cova

Last crawled date: 3 years ago

A filament spool hanger designed to mount on the edge of a shelf - it can be used just to store your filament, or if the shelf is close by you can feed your printer directly from the spools where they hang. I wanted to keep it simple, flexible, and 100% printable - no metal parts are required (bearings, rods, etc.). But if you want to combine some metal parts into your implementation these hangers will work with that too. The STLs included here are sized to fit the shelf above my printer, but the design is fully parametric so you can use the Thingiverse Customizer to fit them to whatever size shelf and spools you happen to have, within the limits of your printer of course.
There are 5 separate components all potentially generated from the single design - I recommend letting the customizer generate all of the ones you need together to ensure they are all compatible, and then using your slicing software to separate them for making multiple copies of some, or printing different parts with different settings.
If you would like to see additional mount options for the top part of the hanger, please leave me a comment describing it. I'm currently considering doing options for screwing it to a horizontal or vertial surface, or to clamp around a piece of extrusion.
I've left it tagged as a work in progess for now, although at least for my needs I consider it finished. But I haven't tested every combination of odd parameters that people might want to use and its possible that some combination will cause a bug. Once I've seen a bunch of other customized versions go through and have more confidence I will remove the tag.
List of included parts
The Clamp
The clamp is the main part, designed to slide over the edge of a shelf and hang down with a hook at the bottom - you will need at least two of them (one on each end of a rod). The hook at the bottom is sized to grab a rod of the configured diameter, but in my testing these clamps are strong enough that if you used a longer non-printed rod (say a metal threaded rod) you could easily hang 10+ spools from just a single pair of hangers. Regardless of what kind of rod you plan to use - entering the correct dimension in the customizer will ensure that the hooks get a good grip on it. For my use, I printed the clamps in PETG, at 0.2mm layers, 3 perimiters, and 20% infill - and I can pull with all my strength and cannot break them with pulling force alone.
The Screw
The screw part is designed to thread through the bottom of the clamp, and clamp it against the shelf. Not much else to say about it. I had a few minor issues with snapping them, and so printed them at 90% infill, but otherwize the same settings as the clamps. For a better grip on the shelf, I also printed mine with a filament-change 3 layers before the top, doing the top three layers in a flexible filament to be squeezed against the shelf.
The Rod
The rod again is very simple - just a rod. The default diameter of 16mm matches the size of the studs on the stock Prusa Original i3 MK2 spool holders, and also the size of the cups on my modified MK2 spool holders, so I kept that size here too so that I could re-use my existing rods. I print them at 0.35mm thick layers and with a 10mm brim, keeping the 3 perimiters and 20% infill as the clamp. I recommend making these as tall as your printer is capable of printing. Or as an option use a metal or wood rod to go even longer - just remember to still set the customizer for the correct diameter as it is also used in the hook on the clamp part.
Optional: The Gasket
The gasket is a single-layer-thick (0.2mm) square of material sized to fit inside the clamp - its purpose it to help give the clamp better grip on the shelf. I print these out of flexible material and then superglue it under the top of the clamp, so that the weight presses it down onto the shelf. If you find your clamps slide too easily on your shelves you can use these, or can use any other high-friction material to stuff in there - I've also used paper-towel folded over a few times which is also quite effective.
Optional: The Test
The test object is just a threaded nut, where the threads have exactly the same parameters as the threads in the bottom of the clamp. If you are customizing the screw and want to test if your threads will work without having to print an entire clamp, you can save some time and plastic by printing the test object. It has no other purpose and is not designed to be used in the final assembled clamp. For accurate testing, print it with the same settings you intend to use for your clamp, and leave it oriented as it is. The clamp threads will be printed at that orientation where the overhang/bridging at the top can cause issues with the threads, which is the primary thing that needs to be caught in testing.