This thing will hold your spool of thread in a horizontal position while you sew. This is helpful when sewing some of the plastic metallic threads, because it reduces the amount of twisting that takes place as the thread is pulled from the spool.

I have included both the complete thing as well as one that is split, to facilitate printing without supports. I printed mine in ABS and glued together with ABS juice (ABS filament mixed with acetone).

UPDATE: Added a nib to the end of the rod to keep the spool from slipping off. Also made the mounting hole triangular for a better friction fit.