There is an updated version of this model. It's easier to use, easier to print, and more durable. The updated model can be found here: https://makerworld.com/en/models/485527#profileId-398011

I created this tippet holder to be used with my Fishpond chest pack. The crossbar pushes through both sides of the bracket and has a “knob” on the end that locks into the far side of the bracket when you twist the crossbar counterclockwise. It should hold up to 7 spools of tippet. In the attached photos I have on 6. I have included step files for the two separate parts and the fusion360 file I used to design it.

Printing Tips: The bracket should print just fine without a brim if your first layer adhesion is good. The crossbar I printed vertically with the knurled knob down. I needed to use a brim to get this to stay on the bed at the higher layer heights. 0.20mm layer heights should work but I printed at 0.16.