Shelf Mounted Spool Holder

I needed to relocate my spool because it was a pain to reach around the printer on the shelf it sitting on, so I came up with this mount that clamps to the rack itself.  The exact shelf I have I got years ago and I don't remember where but I have a link to one that is very similar to it. 

In theory it will clamp to anything that is 25mm in diameter. If yours is a little smaller then doing a loop of electrical tape will help it grip. It does not lock into the grooves as I wanted it to be universal if you wanted to mount it to something else. The pressure from the two screws are enough to keep it in place, but still let it swivel if you need to adjust it. 

I designed it to using #10-24 x 1.5 nuts and bolts. For you metric folks a M5 x 40mm should work too. 

I have included a stubby version that holds the spool a little closer to the rack so it takes up less space. 

https://www.amazon.com/Amazon-Basics-Adjustable-Shelving-Organizer/dp/B018YLFJX4