HHC 2024: HP-65 Restoration Chapter 1 and Trivia (Geoff Quickfall)

[@The.Doctor.Venkman]

Another great presentation and extremely interesting. Thanks, Geoff!

[@InssiAjaton]

I have an HP 67 whose roller got nasty gummy. I got most of it out after repeated sticking to my fingers and any tools that I tried. But i have yet to find any suitable hoses or materials to rebuild it. I even asked a polymer chemistry friend of mine for any hints, but he did not know either. Silicone?? I guess I need to try. On the other hand, I already have the emulation app on my iPad Mini. And then, I also have, and occasionally use my slide rule. It resides on top of my desk top computer. Mostly I do my calculations in my head, but sometimes I want just one more digit of resolution. Anyway, interesting presentation - Thanks!

[@geoffquickfall]

Silicon tubing: outer diameter 5.5mm; inner diameter 2.5mm O-Rings: outer diameter 6.5.0mm; inner diameter 3.0mm The reason for the difference is that the tubing will stretch to fit the pinch roller axle and take on the correct measurement. My silicone tubing is mil spec *the hole is in the exact centre” obtained from a RC hobby shop. If the pinch roller has gone then the dampening couple will go if it hasn’t already. Both repairs are covered in the talk. Cheers