I learned many years ago that the only economic way to make turned parts that have flats and cross-holes is with a swiss screw machine. I got quotes for a small part from CNC shops of $2-$3 each for 5,000 parts. One shop was kind enough to direct me to look for swiss screw machines. Their cost was $0.30 each. Re-chucking parts by hand is very time consuming and costly.
I remember them when all the slides/alternate ops were made by cams!
In my previous life, gas cooker jets were made on them - included a sapphire burnishing op as final bore sizing. Used to buy millions p/a - never had a problem once the sapphire size was established.
"I remember them when all the slides/alternate ops were made by cams"
They still are in some places. JJ Steuby is one screw machine shop that I think still runs them. If you can find the 75-year old machinists that can keep them running. One business owner called those machinists his "Swiss Gnomes" - they were semi-retired, and would come in to set up the machines when he needed them. I suggested that he should get them to train some young kids how to do it, but he was ready to retire himself and not interested in the hassle.
I love how the swiss machine manufacturers always demonstrate their products cutting brass. It looks impressive with the high cutting speeds, flying chips, no coolant, and shiny finished surface. I'd be more impressed with a demonstration machining something nasty like inconel or titanium.
