Abstract: A split spool assembly for discharging filament to a three-dimensional printer is provided. The assembly includes a first spool part having a first reel collar angularly spaced from an axis and a first hub portion, which is disposed about the axis and angularly spaced from the first reel collar. The assembly further includes a second spool part having a second reel collar angularly spaced from the axis and a second hub portion, which is disposed about the axis and angularly spaced from the second reel collar. The first and second collars are spaced from one another for storing a predetermined amount of filament therebetween. The first and second hub portions are disposed about the axis and terminate at associated first and second ends, with the first and second ends being positioned adjacent to one another such that the first and second hub portions are arranged in series along the axis.

Abstract: A vibration resistant fastener comprising a pin and a collar. The pin is threaded or peripherally grooved. At a central location, the major diameter of the thread or groove is reduced to a diameter which is still larger than its minor diameter. A collar is threaded or swaged on to the pin and collar material is pressed into an open region that was formed by the reduction of the major diameter, to form a thread lock.