Content deleted Content added
Hydrargyrum (talk | contribs) Added Gerber Scientific to historical notes |
Hydrargyrum (talk | contribs) m →Historical notes: ANSI --> EIA |
||
Line 18:
Record/playback is different than numerical control in that the program is produced by the machinist in the process of making the first part. The Air Force wanted numerical control and not record/playback because 1} the latter put the machinists who were union members in charge of program production, thus union strikes could result in unacceptable delays in military production, and 2) numerical control demonstrated the capability of producing complex parts that were not possible by the conventional manual methods used in the record/playback technique. The Air Force used its deep pockets to get its way and while American manufacturing may have been better served by the simpler Parsons concept or by record/playback, today this is a moot issue.
The electronic files used to control NC and CNC machines are often in a format called [[G-code]], after [[http://www.gerberscientific.com Gerber Scientific Instruments]], a manufacturer of photoplotters and developer of the file format. The X-Y two-dimensional motion of photoplotters was extended to include the third Z axis, and along with special codes, allows milling machines to be steered in more than three axes. Many of the lines of text in the control files start with the [[ASCII]] letter G, thus the name; however, there are other commands that start with the letter D and M, as well as X and Y for coordinates. The file format became so widely used that it has been embodied in an [[
==Today==
| |||