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SmoothStepper USB / Re: Welcome to SmoothStepper forum.
« on: July 14, 2008, 08:04:13 AM »
Hi Perfo,
You would think that the spell checker on a CNC forum would be set up for that acronym!
Anyway, I have assembled and tested several machines with Mach, and it works pretty good most of the time, but every now and then I will have a "fussy" machine. These are stepper machines with no feedback encoder - completely open loop. I have tried several things to attempt to fix the problem (grounding, shielding, settings, mechanical changes, etc.) to no avail. The problem seems to be the Windows operating system. The reason I say this is because we have seen an improvement in our machines by changing Windows XP to standard PC mode, and making other changes that seemed to improve the consistency in operation of the CNC equipment. Even though we use the same PC model from the same manufacturer, and everything is set up exactly the same from one machine to the next, we will still have an occasional issue with some of the CNC's missing pulses. The point I am making here is that Mach (via the 25 pin parallel port) does work nicely most of the time, but every now and then you will get a fussy PC or Windows system that will not cooperate properly.
The Smooth Stepper takes the "Windows" issues out of the equation when sending pulses to your motor drives. When you use Mach with the parallel port, it essentially turns your PC's processor into a pulsing engine, sending the pulses out to your machine to control motion. This creates a major load on your processor, and other things on your PC. This is why you should designate a PC with Mach only, when using it to run a machine. When you use the Smooth Stepper, Mach sends "trajectory information" to the Smooth Stepper, which then generates the pulses and sends them to the machine through its own processor (in a nutshell). This eliminates any Windows issues when running Mach, but still lets you use Mach's nice interface to control your machine.
I am testing a Smooth Stepper now, and working on tweaking it in. So far, I am impressed with the smoothness, compared to coming out of the parallel port. The homing sequence is a little different, and there are some timing delays for program pause, etc. but consistency is most important to me. You can also run a G-code program, and actually do things in Windows, and the machine will keep running! If you used Mach before, you would understand what a positive change that is. I will keep posting on my results.
You would think that the spell checker on a CNC forum would be set up for that acronym!
Anyway, I have assembled and tested several machines with Mach, and it works pretty good most of the time, but every now and then I will have a "fussy" machine. These are stepper machines with no feedback encoder - completely open loop. I have tried several things to attempt to fix the problem (grounding, shielding, settings, mechanical changes, etc.) to no avail. The problem seems to be the Windows operating system. The reason I say this is because we have seen an improvement in our machines by changing Windows XP to standard PC mode, and making other changes that seemed to improve the consistency in operation of the CNC equipment. Even though we use the same PC model from the same manufacturer, and everything is set up exactly the same from one machine to the next, we will still have an occasional issue with some of the CNC's missing pulses. The point I am making here is that Mach (via the 25 pin parallel port) does work nicely most of the time, but every now and then you will get a fussy PC or Windows system that will not cooperate properly.
The Smooth Stepper takes the "Windows" issues out of the equation when sending pulses to your motor drives. When you use Mach with the parallel port, it essentially turns your PC's processor into a pulsing engine, sending the pulses out to your machine to control motion. This creates a major load on your processor, and other things on your PC. This is why you should designate a PC with Mach only, when using it to run a machine. When you use the Smooth Stepper, Mach sends "trajectory information" to the Smooth Stepper, which then generates the pulses and sends them to the machine through its own processor (in a nutshell). This eliminates any Windows issues when running Mach, but still lets you use Mach's nice interface to control your machine.
I am testing a Smooth Stepper now, and working on tweaking it in. So far, I am impressed with the smoothness, compared to coming out of the parallel port. The homing sequence is a little different, and there are some timing delays for program pause, etc. but consistency is most important to me. You can also run a G-code program, and actually do things in Windows, and the machine will keep running! If you used Mach before, you would understand what a positive change that is. I will keep posting on my results.