On Mon, 13 May 2013 17:56:20 -0500, you wrote:
>A program wouldn't have to give up it's ability to understand G code to >understand additional instructions. For example a canned routine for >drilling doesn't mean the control no longer understands milling >instructions. I never said it did. >My Anilam control only had 1000 instructions program memory >but by using loops it could execute much more than 1000 instructions per >press of the start button. As an example, one part I made was cut out in a >sheet of Delrin, the size of piece that fit in my vise allowed me to machine >3 rows and 7 columns, 21 pieces. By using nested loops I was able to >machine all 21 parts using the code for 1 part repeated in 3 rows and 7 >columns. You missed my point - the loop didn't make the machine move faster or produce a better product. Loops were essential with old controls with limited program memory and are still commonly used, as are canned cycles, but they have their downside too. No feed hold in cycles is a classic. If it's a $5 part - it doesn't matter if you trash it. If it's a $5000 part you need to be able to pause ASAP and try and fix what went wrong before too much damage is caused. An extreme example of unusual code is used by a company I know that makes a wing part for Airbus. Job starts with a huge block of Al, 20 hours later over 80% of it is swarf. The whole program consists of G0 commands - No G1's or cycles anywhere! The machine runs flat out all the time! Crazy, but it was the biggest gantry style CNC machine with the fastest spindle they could get quickly when they got the contract. It works profitably for them so they haven't bothered to upgrade the machine. They replaced it with an identical machine when they wore the first one out! (Same company also bought a big new CNC milling machine that only just fit under the flat roof of the factory and then discovered there wasn't enough clearance above the machine to service it. Simple fix - they cut a hole in the concrete roof, then screwed an 8ftx4ft garden shed down over the hole :) >So continuing the same idea, if the program understood it, I could define >one part, a turbine blade maybe, and repeat the part multiple times rotated >to different positions. When you have so much memory and hard drive space >it hardly seems worth writing efficient code, but if you can correct one >blade it could correct every blade, versus having to edit the same problem >for every different blade. Agreed - but in that case I'd just redo that step in CAM and re post process. >I wish LinuxCNC understood G code plus something like C++ or Basic language. Only a programmer would wish that :) Steve Blackmore -- ------------------------------------------------------------------------------ AlienVault Unified Security Management (USM) platform delivers complete security visibility with the essential security capabilities. Easily and efficiently configure, manage, and operate all of your security controls from a single console and one unified framework. Download a free trial. http://p.sf.net/sfu/alienvault_d2d _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
