Messages

451

SmoothStepper USB / Re: PMDX-126 and SS K1 relay (spindle power) control

« on: January 31, 2011, 06:17:51 PM »

I'm not sure I follow. If you have the SS externally powered and turn off the external power supply it will of course shut off and the PC won't see it any more. If you have the SS powered by the USB cable it should always show up.

452

SmoothStepper USB / Re: PMDX-126 and SS K1 relay (spindle power) control

« on: January 31, 2011, 10:16:14 AM »

You just need to tell Mach to let you back off the limit switch (in configuration). Or, better yet get the Soft Limits set up and you'll never have to worry about hitting a limit.

453

SmoothStepper USB / Re: PMDX-126 and SS K1 relay (spindle power) control

« on: January 31, 2011, 07:01:27 AM »

Take a look at the 'Installation Tips' document in the SmoothStepper section here:

http://www.soigeneris.com/Documentation-content.aspx

. Typically the problem with loosing communication is related to how Windows is set up.

454

SmoothStepper USB / Re: PMDX-126 and SS K1 relay (spindle power) control

« on: January 30, 2011, 09:44:43 PM »

Attempting to get the motor control relay that is on the PMDX-126 to work.  I configure the ports/pins to use port 1, pin 2, for step and port 1, pin 14 for direction for relay K1 and K2 respectivly.

Huh? Why are you trying to turn a relay on with a step/direction signal? What you need to do is look in the 'Spindle Setup' tab in Ports&Pins under 'Relay Control'. Set the Output number to the logical output you want triggered when the spindle is told to turn on in the forward and reverse direction. For example set M3 to Output #1, and M4 to Output #2. Now go to the 'Outputs' tab and set 'Output #1' and 'Output #2' to the proper port and pin numbers.

455

SmoothStepper USB / Re: New CNC member – – Mach3 crashes/unstable

« on: January 21, 2011, 07:48:15 AM »

I sent home another controller and it worked fine. I'm still not sure what the issue with the first one was. I bought one of the same PCs he was using (the Shuttle) and hope to have it set up this weekend (maybe Sunday as I'm leaving to help out with the FIRST Tech Challenge today.) I'll post what I find in case it is useful to other folks.

456

General Mach Discussion / Re: Mach under Windows 7 64 bit- XP Emulation-Again-Help

« on: January 19, 2011, 07:15:16 AM »

A stepper motor would make a lousy spindle, the faster it spins the less torque it has. Besides that you can do threading with a regular old spindle motor. You just need to add an index sensor to it (one pulse per revolution). This will let Mach sync its movements to the spindle.

457

General Mach Discussion / Re: Why is there no effort for the true closed loop control on the mach3 level

« on: January 14, 2011, 04:17:28 PM »

Sam, I'm not trying to give you a hard time. Nor am I saying that what EMC does is not great. There is just a lot of mysticism related to 'closed loop back to the control'. All I want to do is get the facts out and let everyone decide what type of control they want/need.

step servos or steppers machines don't do that.  Emc or Mach blindly sends out pulses that relate to how the control wants the motion to go.  Yes - you can setup the step servos so that if they loose position - the machine will estop (rogersmachine interface gets you at least position - if I understand it right)...  but I don't consider that 'true close loop' as the control doesn't know its position at that point and isn't reading back and constantly correcting while moving.

You have the general idea, but you don't quite right. EVERY servo system knows exactly where it is, that is what the encoder tells it. EVERY servo system is never exactly where you tell it to go, there is always a bit of error. If the error is too great you get an error signal. Simple servo drives keep all the encoder information to themselves but will tell the controller if the error is too great. The important part is that they go where they are told or an error is generated, the controller that is telling them where to go knows exactly where they are unless an error occurs. If an error occurs than your part/fixturing is likely scrap so it does not matter either way.

More complex servo controllers can share the encoder position with the control logic and the control logic can 'sync' multiple axis movements together. So, if one axis is lagging behind everything can slow down and you might be able to avoid an error. For 99.99% of cases this ability to 'sync' axis' together dynamically is superfluous. Why? Well if what you are doing is bogging down an axis to the point of tripping an error then you have most likely ruined the part and/or tool anyhow. For some operations like threading it is important to synchronize the axis' movement with the spindle. This really only requires an index pulse from the spindle for single point threading. For more complex operations you need more synchronization, but again that is outside what is really needed for the vast majority of cases.

458

General Mach Discussion / Re: Why is there no effort for the true closed loop control on the mach3 level

« on: January 14, 2011, 10:08:21 AM »

closed loop

Closed loop is closed loop, there is to 'real' or 'fake' about it. The implementation may differ from system to system but that does not make one implementation more 'real' than another.

I can estop the machine without rehoming.
while the servo drives are disabled I can move the machine around without it loosing its position.
The machine will go into estop if my following error is greater than the amount I have set.
The dro is displaying actual machine position - not what it thinks the position is.

You can do all of these things in Mach as well. EMC approaches things a bit different than Mach and does a few nifty things itself that Mach does not. But, motion control done on a PC (real time OS or not) will always be inferior to motion control done via a motion controller in dedicated HW. This is not because EMC or Mach is deficient, it is a limitation of the PC hardware.

459

General Mach Discussion / Re: Windows Project (;-)

« on: January 13, 2011, 03:01:09 PM »

so if you're judging based on a SS system that might not be true for a PP system.

As I said I have run this machine both ways and I have installed Mach on many other machines and I have done support on many more than that. I have a pretty good base form which to form my opinions.

460

General Mach Discussion / Re: Windows Project (;-)

« on: January 13, 2011, 12:31:48 PM »

BTW, Jeff, isn't it with the Smooth Stepper?

Isn't what with the SmoothStepper? I do use the SmoothStepper 99.99% of the time. The PC I mentioned also has a parallel port and I have used it, at 25mHz, also. With the SmoothStepper I can have CamBam open and be using it while cutting but not with the parallel port. Removing a bunch of stuff that is not being used, Internet Explorer, etc, etc is not going to make it work any better.

I can tell that stripping all the unused features of XP using the XPlite software made the PC (which is far not the best out there nor a new) boot VERY fast. 23 seconds to fully load Windows! About 20 seconds faster than before I stripped it. Not that it runs Mach3 better this way, I just like it being loading fast.

Right, booting faster does not make any difference in how Mach runs but it is nicer.

Yes Jeff the idea is to get the BLOAT out of the install AND free up resources AND free up CPU time/interuptions.

It certainly does not mean you have to give up networking BUT for those that do not require it why not. If you feel it is not for you then please do not feel obligated to participate.

The point I'm trying to get across is that you need to be sure there is a problem before going to a lot of work to fix it You have assumed that a regular Windows install is full of bloat (because everyone says so) and that there is all this stuff you can remove that will make Mach work better. That makes sense when you think about it but there is plenty of evidence to suggest otherwise so what is the truth?

Judging by all the computers I have set up with Mach and all the conversations I have had with customers the most beneficial thing to do is to start with a fresh install of Windows, turn off the power savings stuff, and don't install a bunch of stuff on the computer. Most 'bloat' comes from installing a bunch of software. Most software nowadays wants to install/run some bloody service to check for updates. So you have all of these programs running all of these services to check and see if there is an update. I-Tunes is a classic example of this, in normal computer use you would never notice this but when running Mach it can make Mach hiccup. There was a thread on the Mach Yahoo group recently about a recent Adobe reader update that caused similar problems.

My

much faster dual core PC with 3 years of programs installed takes well over a minute to boot, and uses over 400MB of RAM.

That is exactly what I'm talking about.

I know OEMs that use Mach and have a Windows XP Embedded build that they use. They have gone through and chosen what to include in the build based on what their machine needs. Since XP Embedded has a longer supported life, and the install is vendor specific, and you can possibly control what a user can do / not do to the underlying operating system and screw things up it makes a lot of sense.

For the average Mach user I'm not sure that a 'striped' down version of XP will make any difference. Dedicating a PC for the CNC control and not using it as a general purpose PC is a much more beneficial move for most folks. Another big down side of stripping things out of a standard Windows install is that you may find your missing an important part if you change a piece of hardware. We use a stripped down version of both XP and Win7 at the university that will boot off a CD or small thumbdrive for installation and troubleshooting purposes. To get Windows in that kind of space you have to be very specific about what HW it will run on (all drivers have to be included on the CD.)

In short I'm not saying it is a bad idea, and it is very interesting from the standpoint that it would be a fun exercise, I'm just saying that it may not be a big advantage like you might hope.