Wednesday, June 8, 2011
Ideal Harmonic Transformer prototypes
These prototypes use #6 machine screws. I had reasoned that they are already designed, readily available, and quite strong, so no need to reinvent. However, I could not find any off-the-shelf hardware that let me do what I wanted with the arm pin and yoke pin. After spending too much time in front of the fasteners at Lowes and Home Depot, I decided maybe it was possible to make plastic screws after all.
Once I got the hang of it, I converted all of the screws to home-printed rather than OTS. This let me eliminate all the nuts, by "tapping" the holes, which made the whole design cleaner. It also let me decorate the heads to go with the overall look, not to mention saving me the frustration of sorting through the store's wares.
One limitation, at least with my printer, is that threads must be printed vertically in order to work. The down side is that a print is basically a bunch of laminated heat-welded layers. I think this gives a certain grain to the finished material, and is contributing to the failures I'm experiencing. Some of my bolts snap off at the head right as I'm taking them off of the machine. Others turn out fairly strong. Setting the Up! print settings to fill=solid and quality=fine helps, but does not eliminate, this problem.