Cad Cam

Boswell, both sides require some creativity depending on the part and experience of the user in machining. That is not a cad/cam exclusive. I do have experience with cad/cam starting in the early 90's with ez-mill and shop floor programming. My opinion is you either waste time with calculator or waste time drawing the part. It's very generalized I know but that is how I feel when I talk about it. Neither is really exciting now days.

I do like the moon reference. My old man started me out on a manual mill when I was young. So much for child labor laws:)
 
Boswell, you commented that 'we sent people to moon without using CNC', I honestly don't think that's the case, in the aircraft industry in particular, NC, the predecessor of CNC was widely used particularly for 'skin mills' and other complex surfaces starting in the mid 50's. Other than that, I agree, CADCAM takes a lot of the manual calculations out of programming and for complex surfaces, just simply makes them possible.
 
L98fiero said:
Boswell, you commented that 'we sent people to moon without using CNC', I honestly don't think that's the case, in the aircraft industry in particular, NC, the predecessor of CNC was widely used particularly for 'skin mills' and other complex surfaces starting in the mid 50's. Other than that, I agree, CADCAM takes a lot of the manual calculations out of programming and for complex surfaces, just simply makes them possible.
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I recall reading about some guy who did NC the hard way when making airfoil templates for NACA in the forties. He did all the calculations, tabulated the numbers, put a machinist on each axis of the mill, and then read off numbers to them.
 
I had subroutines built for that. Spiraling in to depth, pulling out and doing it again with .003 more on the OD. That and many other routines. Ten years of running two different machines, one a vertical with a 30 by 40 in table, and a horizontal. I had a 12 by 12 angle plate mounted on the table for the horizontal, used it like a vertical.
 
Thanks for the correction on NASA and CNC. I personally did not know and only was repeating what someone else has posted once that had the "ring of truth" After all, if you read it on the internet, it must be true :)

Ok, I did some research and learned a bunch about the early days of NC and then CNC.
Wikipedia credits John T. Parsons with developing the concept of NC control using the system that John mentions above with multiple operators. He did this for Sikorsky to make rotor blades sometime around 1946. it was called "By-the-numbers method" and later used some punched cards.
In 1950 MIT took a Cincinnati "Hydro-Tel" mill and fitted it thre refrigerator sizzed cabinests to control X, Y and Z.
Parsons recieved a patent for "Motor Controlled apparatus for positioning machine tool in May of 1952 and then MIT filed a patent for Numerical Control Servo-System in August of 1952

So it seems clear that NASA would have had access to CNC type machines for the Apollo program but it is not clear how much they were used.
The Wikipedia article is quite interesting
http://en.wikipedia.org/wiki/History_of_numerical_control
 
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