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« on: October 27, 2006, 03:50:44 PM »
Backlash is a problem, period. I personally think art should just remove it. It is very rare that a system can use it. It isn't art's fault. when you really sit down and think about what backlash correction is doing the problems become obvious. 95% of stepper systems are going to choke on backlash compensation. I have tried it on two servo systems and also have problems with it.
When I first started with my first cnc retro it took me forever to figure out why my motors were locking up. Then I traced it down to backlash and I like others felt that mach had a bug. After working out what was happening I realized the inherent limitations of backlash compensation.
OK so where does this leave us? The best thing to do about backlash is get rid of it in the machine. No amount of software is going to fix it. When you are cutting the bit will pull the work into it because of the mechanical backlash and this is something that the computer cannot fix.
Backlash will absolutely not work in constant velocity, it HAS to be run in exact stop mode.
Wawatobi, I think the problem you are having is related to you feed back from the steppers and using back lash. From what i can gather if your stepper feed back realizes that you aren't where you should be it triggers an estop. When using backlash with steppers it is usually described as steppers stalling ( a common occurrence with back lash ) with your stepper position monitoring system it is bound to trigger an error and halt your code.
It is no ones fault, it just is what it is.
Chad