This clip snaps snugly around a standard sewing bobbin, preventing the thread from unraveling.
This is a great accessory to the Modular Sewing Spool Holder (shameless plug) - clipped bobbins fit on top of the spools.
Monoprice Maker Select v2.1
Works great with the flexibility of PETG - have not tried it in other materials.
I designed this for FDM printers with 0.4mm nozzles. The thinnest parts (at 0.8mm) should slice to two shells thick. There is one negative angle overhang (45 degree chamfer) which should print fine without supports.
Your slicer shouldn't need to generate any infill for this print - it should be all shells. You may need to increase the number of shells to achieve this, depending on your default settings.
I was able to print a plate full of these in PETG without brims on a PEI print bed - but don't hesitate to use a brim if needed.
I took inspiration from a commercial bobbin clip with a similar design, which I measured with a caliper to get the basic dimensions.
I wanted a design that would stand up on end, not roll away, grip and remove easily, and have small protrusions at the opening to help guide the bobbin into the clip.
This was designed from scratch using DesignSpark Mechanical. I also spent waaaaaay too long getting the chamfers and rounds to work the way I wanted in DSM. :-)