On 7/19/2013 5:33 AM, Gregg Eshelman wrote: > On Thu, 7/18/13, John Kasunich <[email protected]> wrote: > > Subject: Re: [Emc-users] query: how long was your longes G-Code program > ever? > To: [email protected] > Date: Thursday, July 18, 2013, 7:48 PM > > > > On Thu, Jul 18, 2013, at 02:04 PM, Stuart Stevenson wrote: > > I had a handful of mylar dots from a tape punch. Andy P called them > antibits. 1/2 million lines would be a large pile of it - :) > > And Mike Payson wrote: > > Like others have said, gcode files for 3d printers van get BIG. > > I export all my gcode to a single directory > > > > I checked, and the largest file there is 1,708,605 lines and 51,650,578 > characters long. > > > > Geek that I am, I just had to do the math: > > If that file was punched onto paper tape, the tape would be 81 miles long. > > The pile of anti-bits would weigh about 25 lbs. > > If you wound the tape onto a single spool, it would be 13 feet in diameter > and weigh about 700 lbs. > > "Hey Stuart, we have a new program to load into the Haas. Bring that > forklift over here!" > --------------- > > How many hours would it take to load? > >
Obviously you guys never had to depend on punched paper tape. I ran through roughly a shipping pallet of blank tape---both rolled oiled tape and folded dry tape varieties--- when I was using minicomputers to gather experimental data in the early 1970s on the way to my PhD. With just that small amount of tape processed, I had several times to field strip and repair the mechanical punch and reader mechanisms on my Teletype ASR33 (10 cps read/punch) and the mechanical punch mechanism on my DEC high Speed Paper Tape Reader/Punch (300 cps read, 50 cps punch). 1. The "high" speed unit would take ca 277 hours to punch this job and ca 48 hours to read it running continuously at full speed. Later mylar-tape versions might have reduced these times by as much as 50 percent(?). 2. The chance of reading 51 million characters without error is small, but the chance of punching them all cleanly is zero. Incomplete punches (remember the famous swinging chad?) were the least of my problems. Mispunches and missing punches were a constant threat. Teletype provided a hand punch/block for "repairing" bad punches, which meant punching out all the holes in a row to make it a delete/rubout character. This brute-force solution may have been adequate for Western Union, but it's a nonstarter for a data system. Mylar tape was a much better medium than paper tape but not an ideal medium either. There would still be errors. Regards, Kent ------------------------------------------------------------------------------ See everything from the browser to the database with AppDynamics Get end-to-end visibility with application monitoring from AppDynamics Isolate bottlenecks and diagnose root cause in seconds. Start your free trial of AppDynamics Pro today! http://pubads.g.doubleclick.net/gampad/clk?id=48808831&iu=/4140/ostg.clktrk _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
