On
1 August 2024 at 13:52 MikeK Said:
Interesting. But I bet it was just cheaper to employ humans. That machine is very complicated and getting those stop blocks set to the correct distance would have been a pain.
Mike
I’d take that bet, except it’s unethical to take sweeties away from baby! We know what happened to machine tools after 1951.
Production is not like general-purpose work! Manufacturers introduced various simple forms of automatic in the 19th century, particularly in the US where labour was expensive and skilled labour hard to find. Production demands cheapest possible output, meaning fast methods and low error rates. People are slow, error-prone and expensive. They go sick, fail to turn up, jump ship, steal, start fights, make mistakes, cause accidents, and want more money, better conditions, reduced hours, more holidays, and big pensions.
In contrast, any significant production job that can be done on an automatic will cheaper than the same job done by humans. Plenty of exceptions such as prototyping, repair, and low volume production, but manual production has been in decline since about 1930. When to switch to an automatic is usually only obvious to an accountant; it’s a cost-benefit decision, nothing to do with shop-floor skills.
Automatics started with cam driven machines, then hydraulics, and then electro-mechanical. Electronics rule today, almost everything is computer controlled.
Cam driven automatics are a major pain to reconfigure, and can only perform a small number of operations. Quite specialised, and only paid if hundreds of thousands of identical parts were needed. Hydraulics and electro-mechanical automatics opened the door to being programmable, reducing the size of the minimum economic production but still many tens of thousands.
As can be seen on the Burnett machine, electro-mechanical technology severely limits the number of operations a program can do. I doubt many Man-Au-Trol machines were sold, because electronic controllers were on the horizon, and these are more capable. And the Man-Au-Trol was competing with tape-controlled machines too.
Modern CNC is a different world : enclosed machines with up to 12 axes, a tool-change autoloader, and maybe a conveyor belt to remove the few tons of swarf it makes per day. Parts are modelled in 3D-CAD, from which g-code is generated, and loaded straight into the CNC machine. The operator isn’t a conventionally trained machinist and he’s probably responsible for several machines: skilled work, but not as a 1948 Myford owner might understand it!
Over the years prices have dropped, making CNC as an on-line service viable even for amateur one-offs. Ten years ago, far too expensive. Still expensive by my standards, but much closer to my budget. Worth keeping an eye on!
Dave