3DPN Shelf Spool Holder - Brien Allison

myminifactory

My entry for the 3D Printing Nerd Shelf Spool Holder design contest is now submitted. When designing this spool holder, my goal was to maximize strength and simplicity within the specified design constraints of the competition. I was particularly concerned that if I attached the spool holder only to the front timber, while it would easily handle vertical loads, the twisting moment from the spool holder could cause damage to the shelf brackets, especially when many were attached to the same timber. For this reason, I chose a levered design where the bending moment from the spool is held in place with vertical forces on both the front and back timbers. To reduce stress concentrations at the corners, I used large fillets and undercuts, and adjusted the thickness based on the bending moment along the beam. This design provides excellent security when holding a spool but can be easily removed by unhooking it from the front. It can be positioned anywhere on the shelves without interfering with or requiring the relocation of stowed filament spools. This prints all in one piece, without any support material, in an orientation that maximizes strength. However, this does mean it is relatively long (about 320mm) and won't fit on my standard 200mmx200mm print bed; the printed example is at 80% scale. I've also included the Fusion 360 file for making minor adjustments if needed. Update: I've made changes to the model's text to make it larger and easier to print overall.