CMC Choke Ferrite Slug Form

To get the most effectiveness from any inductor it's important to have consistent spacing of the conductors, and not to cross over the same layer wraps, otherwise they cancel. I've found it very challenging to hand wrap my common mode chokes (AKA Line isolators) and have the coax stay in place and tight to the inner walls of the ferrite, which is why I created this very simple 3D print. This slug is inserted into the center of a ½" I.D. ferrite bead, and for HF frequencies mix 31 gives the broadest coverage. The slug permits nine wraps of RG-316 coax, which will use approximately 3 ⅓ feet of coax, and provides approx. -40 to approx. -26 dB from 3.5 to 30 MHz of common mode attenuation, for much less that the typical US$75 factory chokes on the market. Constructive feedback is welcomed.