Tippy

Tippy is done! In the end I found out the switch had a very definite cut-off at 3mm, so I was able to thread the switch in until it contacted the ball, back it out two turns to get 2mm of clearance, and 1mm of translation of the ball would break the circuit. I cut the headspace down to 5mm, leaving a good healthy margin for error, and was able to re-draw the part using 2" diameter bar stock. It wound up being about half the volume of the original design.

The other big change is that I went from four M4 socket head cap screws to four M3 socket head flat head screws. It makes for a cleaner look, in my opinion. The mounting holes were also changed from M6 to M5, leaving more threads engaged albeit in a smaller diameter screw. (A single M6 screw could easily hold my car off the ground without breaking... the whole switch assembly weighs less than a pound... c'mon!)

Tippy triggers pretty consistently at 20 degrees plus or minus a small bit. The spec is 20 +/- 1, so I think we make it with room to spare. All that's left is to package the power supply and optoisolator, which is just drilling holes in a Bud or a Hammond box. Done!

That's always the real thrill with making something you designed from scratch: having it look better than your 3D renderings of the CAD model. This one came out AOK.

Tom