Originally Posted by Carl@Semroc

That is a lot of questions!

To listen to Vern (and Gleda) describe the original Mabel was very exciting for me. It was so different from our machine. Vern was a master of fluid logic design. The original and probably its siblings used no electricity at all. It was all hydralic rams and valves. Even the switches were valves.

We started with hydralic and quickly moved to air. The red hydralic stains were a real nuisance, but the real problem was with speed. Air moves much faster than hydralic fluid. When I asked Vern how he moved the ram so fast (to complete one cycle in 5.5 seconds), he almost matter-of-fact said he moved it down until it hit resistance with a high volume, low pressure supply, then switched it over to a low volume, high pressure supply to do the final pack. Once it hit the pre-set pressure, it switched back over to a high volume, low pressure to move the ram back out of the way. THAT is something that I did not think of. Vern was a genius!

I am not sure what the level of interest in actual engine machine design is.