Robert, thank you for your response and the time you've put into this. I've been thinking about this and wonder what the ultimate solution for my situation could be. It likely will involve variable feed rates, however I've been wondering how I could tie the feed rate to the motor load. I'll try to get my head around this as I move forward on my project.
I don't remember what I shared before about my application and history. In early 2010 I did some experimenting with EMC2 and a single axis linear actuator for creep-feed grinding, and rapidly gained the confidence to put together a 4 axis machine, basically configured as a mill with a rotary indexer. I was doing all this on my own nickel to develop a process for making a family of parts for a customer. This was put together using Gecko drives and steppers with then current version of Ubuntu and EMC2. The machine came together beautifully with the mechanical aspects (ball screw installations, motor hardware, limit switches, etc.) and with the configuration of EMC2. I had hired a friend who was electrically and computer savvy to help me and we had a great time overcoming every obstacle in our path. And the results still work great! The customer's orders for the product have fluctuated in the years since, and we have been able to use this machine to good effect, except that last fall they finally gained some market traction and the production needs took a jump (Yay!). Back when I finished the first machine, I had an opportunity to pick up another donor machine for what I envisioned as rev 2 for this project. It is a Harig Slicer with a larger enclosure, higher HP spindle, already outfitted with motor mounts and a ball screw on one axis. I have worked on this slowly in the interim, primarily replacing the hydraulic longitudinal axis drive with ball screw. With the uptick in orders, I have accellerated my attention on this project, trying to apply our learnings from Grinder #1. G1 had been placed in a subcontractor's shop these past couple years and I have recently brought it back to my place (the subs could no longer keep up on their part time basis) and I'm able to keep it running two shifts per day. So now I am working to get the Harig (G2) into production, although it has taken a back seat to my attention on reinstalling G1 and resuming production. G2 has the latest software releases and I have gotten as far as powering the drives and motors but have not done any final calibrations. I may have a limit switch or two to hook up. I've also got an MPG to work. Driver settings. I've got some numbers that allow it to move, but I read right here that I should be sure of these numbers! ;-) I couldn't find the KL-8082H on: http://wiki.linuxcnc.org/cgi-bin/wiki.pl?Stepper_Drive_Timing So I will be happy to share what I learn. There is some information on this document: http://www.automationtechnologiesinc.com/wp-content/uploads/downloads/2012/06/KL-8082H.pdf But in my ignorance I lack confidence in my interpretations. Maybe some of you know something about these drivers? (Shouldn't have bought them, maybe?) They are closed-loop steppers, and I bought them from Automation Technology Inc but the guy basically pleads ignorance with LinuxCNC and says most of his stuff is going to the Mach/Windows users. I wished I'd fleshed this out on this list before I bought 'em... These drivers are supposed handle the encoder feedback and do any necessary travel corrections. As I understand, LinuxCNC has the capability to use the encoders, so maybe I would be better off with Geckos and wiring the encoders back to EMC2? Thanks, Andy E ------------------------------------------------------------------------------ Rapidly troubleshoot problems before they affect your business. Most IT organizations don't have a clear picture of how application performance affects their revenue. With AppDynamics, you get 100% visibility into your Java,.NET, & PHP application. Start your 15-day FREE TRIAL of AppDynamics Pro! http://pubads.g.doubleclick.net/gampad/clk?id=84349831&iu=/4140/ostg.clktrk _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
