Here is a 2 piece case for keeping the pairs of bobbin and thread together. No more searching the box for the compliment color. Once closed, you can shake the case and all stays put. case will also stay closed by itself. I printed this with a 10% infill and 3 shells at .3 mm layer with a .4 mm nozzle.
HungryHam asked for a larger version of this..
"The thread spools I'm using are 72mm tall and have a diameter of 34mm. I love this design. It is just what my wife the quilter needs."