Loading ...
Sorry, an error occurred while loading the content.

Re: [taigtools] Y axis losing steps, stalling.

Expand Messages
  • Rob Ferber
    Hi, Let me preface what I m about to suggest with I m a newbie , that said, here are two thoughts: 1. Has the resistance (or inductance if you have a
    Message 1 of 12 , Apr 1, 2006
    • 0 Attachment
      Hi,

      Let me preface what I'm about to suggest with "I'm a newbie", that
      said, here are two thoughts:

      1. Has the resistance (or inductance if you have a micro-henry
      meter) of any of the windings on the stepper changed (are they all the
      same, nearly, or is one out of line)?

      2. If it involves motion in a specific sense, then perhaps this is
      an anisotropic chatter. If you epoxy a cheap microphone (piezo or
      electret) to a chunk of metal and then bolt that to the table, run a
      spectrum on the sound as you
      move the table. I found an anisotropic chatter in mine that way, though
      I still don't know what is causing it.

      These are just thoughts, I'm certain there are better ones that will
      come your way...

      -- Rob



      Chris Ghent wrote:

      >I've seen others asking about losing steps and thought to myself,
      >thankfully I don't have that problem. Seems like I now have.
      >
      >The steps are being lost in the y axis. I have dismantled and checked it
      >and it all seems smooth and not at all tight in any particular place. It
      >loses the steps no matter where I put the job, from mid left of the ways
      >to mid right. I have checked the acceleration and speed values and they
      >have not changed. The machine has performed well for a year with the
      >current PC so it is not port voltages. I have checked the push force in
      >the x axis when jogging and it is stronger than I am. It manually
      >handles easily and smoothly. I have checked through the archives for
      >similar problems and found no solutions.
      >
      >The steps are being lost in a rapid in which both x and y axes are
      >involved, moving diagonally right and foward. The x axis sometimes
      >stalls completely, at other times it just quietly does not go as far as
      >it should. At the moments at which it is stalled it responds to a flick
      >of the manual knob.
      >
      >I mention these things in the hope that someone who has been there
      >before might recognise some symptom and clue me in on what to look for.
      >I am currently thinking there might be some problem in the Y axis that
      >makes the x axis harder to move when the y axis is moving. Does this
      >strike a bell with anyone? It does not matter where on the y axis the
      >job is, it still happens. I should mention that when the two axes are
      >moving at the same time the machine makes more than twice the noise that
      >just one axis makes. It really groans. The machine has been working
      >extremely well for some time in the current configuration.
      >
      >If the problem has not solved itself overnight (what, that doesn't
      >happen?) I will pull it apart again tomorrow for another look. Any
      >suggestions welcome.
      >
      >I have checked:
      >x gibs
      >x backlash adjustment
      >x and y easy to move with manual knob
      >x and y easy and quiet to move by jogging (x quieter than y)
      >hard to hold back under jog
      >machine settings accel/speed
      >read archives and thought about all suggestions under "losing steps"
      >
      >best wishes
      >
      >Chris
      >
      >
      >
      >
      >To Post a message, send it to: taigtools@...
      >
      >To Unsubscribe, send a blank message to: taigtools-unsubscribe@...
      >
      >
      >
      >Let the chips fly!
      >
      >Yahoo! Groups Links
      >
      >
      >
      >
      >
      >
      >
      >
      >
      >
    • Nicholas Carter and Felice Luftschein
      What control and steppers (oz/in) are you using? If it only happens with combined x/y moves then I suspect it s an electrical issue - the steppers aren t
      Message 2 of 12 , Apr 1, 2006
      • 0 Attachment
        What control and steppers (oz/in) are you using? If it only happens with
        combined x/y moves then I suspect it's an electrical issue - the
        steppers aren't getting enough of what they need from the control.
        Have you run combined x/y moves before without the problem?

        Chris Ghent wrote:
        > I've seen others asking about losing steps and thought to myself,
        > thankfully I don't have that problem. Seems like I now have.
        >
        > The steps are being lost in the y axis. I have dismantled and checked it
        > and it all seems smooth and not at all tight in any particular place. It
        > loses the steps no matter where I put the job, from mid left of the ways
        > to mid right. I have checked the acceleration and speed values and they
        > have not changed. The machine has performed well for a year with the
        > current PC so it is not port voltages. I have checked the push force in
        > the x axis when jogging and it is stronger than I am. It manually
        > handles easily and smoothly. I have checked through the archives for
        > similar problems and found no solutions.
        >
        > The steps are being lost in a rapid in which both x and y axes are
        > involved, moving diagonally right and foward. The x axis sometimes
        > stalls completely, at other times it just quietly does not go as far as
        > it should. At the moments at which it is stalled it responds to a flick
        > of the manual knob.
        >
        > I mention these things in the hope that someone who has been there
        > before might recognise some symptom and clue me in on what to look for.
        > I am currently thinking there might be some problem in the Y axis that
        > makes the x axis harder to move when the y axis is moving. Does this
        > strike a bell with anyone? It does not matter where on the y axis the
        > job is, it still happens. I should mention that when the two axes are
        > moving at the same time the machine makes more than twice the noise that
        > just one axis makes. It really groans. The machine has been working
        > extremely well for some time in the current configuration.
        >
        > If the problem has not solved itself overnight (what, that doesn't
        > happen?) I will pull it apart again tomorrow for another look. Any
        > suggestions welcome.
        >
        > I have checked:
        > x gibs
        > x backlash adjustment
        > x and y easy to move with manual knob
        > x and y easy and quiet to move by jogging (x quieter than y)
        > hard to hold back under jog
        > machine settings accel/speed
        > read archives and thought about all suggestions under "losing steps"
        >
        > best wishes
        >
        > Chris
        >
        >
        >
        >
        > To Post a message, send it to: taigtools@...
        >
        > To Unsubscribe, send a blank message to: taigtools-unsubscribe@...
        >
        >
        >
        > Let the chips fly!
        >
        > Yahoo! Groups Links
        >
        >
        >
        >
        >
        >
        >
        >

        --
        felice@... is Nicholas Carter and Felice Luftschein. See our
        homepage at www.cartertools.com/nfhome.html
      • Steve Blackmore
        ... Hi Nick - got to agree with you here. Mach3 often shows this until the motor tuning is set correctly. You can jog any one axis at a particular speed and
        Message 3 of 12 , Apr 2, 2006
        • 0 Attachment
          On Sat, 01 Apr 2006 21:33:11 -0800, you wrote:

          >What control and steppers (oz/in) are you using? If it only happens with
          >combined x/y moves then I suspect it's an electrical issue - the
          >steppers aren't getting enough of what they need from the control.
          >Have you run combined x/y moves before without the problem?

          Hi Nick - got to agree with you here. Mach3 often shows this until the
          motor tuning is set correctly. You can jog any one axis at a particular
          speed and all seems well until combined moves, then one or more axis
          will stall.

          Usually just a simple fix, reduce acceleration rate and max velocity
          slightly.

          The only other two common reasons are, insufficient power available and
          noise.

          Power supply should be able to supply 2/3rds of the rated amperage per
          axis, so three 4A motors need an 8A supply.

          Noise - Stepper cables should be screened and grounded at control box
          end only and not bundled with any power cables.

          Steve Blackmore
          --
        • Chris Ghent
          I ve seen others asking about losing steps and thought to myself, thankfully I don t have that problem. Seems like I now have. The steps are being lost in the
          Message 4 of 12 , Apr 2, 2006
          • 0 Attachment
            I've seen others asking about losing steps and thought to myself,
            thankfully I don't have that problem. Seems like I now have.

            The steps are being lost in the y axis. I have dismantled and checked it
            and it all seems smooth and not at all tight in any particular place. It
            loses the steps no matter where I put the job, from mid left of the ways
            to mid right. I have checked the acceleration and speed values and they
            have not changed. The machine has performed well for a year with the
            current PC so it is not port voltages. I have checked the push force in
            the x axis when jogging and it is stronger than I am. It manually
            handles easily and smoothly. I have checked through the archives for
            similar problems and found no solutions.

            The steps are being lost in a rapid in which both x and y axes are
            involved, moving diagonally right and foward. The x axis sometimes
            stalls completely, at other times it just quietly does not go as far as
            it should. At the moments at which it is stalled it responds to a flick
            of the manual knob.

            I mention these things in the hope that someone who has been there
            before might recognise some symptom and clue me in on what to look for.
            I am currently thinking there might be some problem in the Y axis that
            makes the x axis harder to move when the y axis is moving. Does this
            strike a bell with anyone? It does not matter where on the y axis the
            job is, it still happens. I should mention that when the two axes are
            moving at the same time the machine makes more than twice the noise that
            just one axis makes. It really groans. The machine has been working
            extremely well for some time in the current configuration.

            If the problem has not solved itself overnight (what, that doesn't
            happen?) I will pull it apart again tomorrow for another look. Any
            suggestions welcome.

            I have checked:
            x gibs
            x backlash adjustment
            x and y easy to move with manual knob
            x and y easy and quiet to move by jogging (x quieter than y)
            hard to hold back under jog
            machine settings accel/speed
            read archives and thought about all suggestions under "losing steps"

            best wishes

            Chris
          • chrisghentone
            Nick Yes, I have run many many similar moves before without any sign of a problem... Chris ... with
            Message 5 of 12 , Apr 2, 2006
            • 0 Attachment
              Nick

              Yes, I have run many many similar moves before without any sign of a
              problem...

              Chris

              --- In taigtools@yahoogroups.com, Nicholas Carter and Felice
              Luftschein <felice@...> wrote:
              >
              > What control and steppers (oz/in) are you using? If it only happens
              with
              > combined x/y moves then I suspect it's an electrical issue - the
              > steppers aren't getting enough of what they need from the control.
              > Have you run combined x/y moves before without the problem?
              >
            • chrisghentone
              Sorry, forgot to say, I am using the standard Taig 200oz setup... Chris ... with
              Message 6 of 12 , Apr 2, 2006
              • 0 Attachment
                Sorry, forgot to say, I am using the standard Taig 200oz setup...

                Chris

                --- In taigtools@yahoogroups.com, Nicholas Carter and Felice
                Luftschein <felice@...> wrote:
                >
                > What control and steppers (oz/in) are you using? If it only happens
                with
                > combined x/y moves then I suspect it's an electrical issue - the
                > steppers aren't getting enough of what they need from the control.
                > Have you run combined x/y moves before without the problem?
                >
              • Nicholas Carter and Felice Luftschein
                Does it only stall in one direction, or if you do a similar move in the other direction does it bind as well? (this would tell if it might be a gib/racking
                Message 7 of 12 , Apr 2, 2006
                • 0 Attachment
                  Does it only stall in one direction, or if you do a similar move in the
                  other direction does it bind as well?
                  (this would tell if it might be a gib/racking issue)

                  Otherwise I don't know, if the electronics are working fine otherwise
                  and it's done it in the past it does point to a mechanical issue or an
                  electrical one above my pay grade.

                  chrisghentone wrote:
                  > Nick
                  >
                  > Yes, I have run many many similar moves before without any sign of a
                  > problem...
                  >
                  > Chris
                  >
                  > --- In taigtools@yahoogroups.com, Nicholas Carter and Felice
                  > Luftschein <felice@...> wrote:
                  >> What control and steppers (oz/in) are you using? If it only happens
                  > with
                  >> combined x/y moves then I suspect it's an electrical issue - the
                  >> steppers aren't getting enough of what they need from the control.
                  >> Have you run combined x/y moves before without the problem?
                  >>
                  >
                  >
                  >
                  >
                  >
                  >
                  > To Post a message, send it to: taigtools@...
                  >
                  > To Unsubscribe, send a blank message to: taigtools-unsubscribe@...
                  >
                  >
                  >
                  > Let the chips fly!
                  >
                  > Yahoo! Groups Links
                  >
                  >
                  >
                  >
                  >
                  >
                  >
                  >

                  --
                  felice@... is Nicholas Carter and Felice Luftschein. See our
                  homepage at www.cartertools.com/nfhome.html
                • Scott A. Stephens
                  Just to ask, what happens if you swap the motors with a good axis??? Does the problem stay the same, or does it move to another axis??
                  Message 8 of 12 , Apr 2, 2006
                  • 0 Attachment
                    Just to ask, what happens if you swap the motors with a good
                    axis??? Does the problem stay the same, or does it move to another axis??

                    At 11:32 AM 4/2/2006, you wrote:
                    >Does it only stall in one direction, or if you do a similar move in the
                    >other direction does it bind as well?
                    >(this would tell if it might be a gib/racking issue)
                    >
                    >Otherwise I don't know, if the electronics are working fine otherwise
                    >and it's done it in the past it does point to a mechanical issue or an
                    >electrical one above my pay grade.
                    >
                    >chrisghentone wrote:
                    > > Nick
                    > >
                    > > Yes, I have run many many similar moves before without any sign of a
                    > > problem...
                    > >
                    > > Chris
                    > >
                    > > --- In taigtools@yahoogroups.com, Nicholas Carter and Felice
                    > > Luftschein <felice@...> wrote:
                    > >> What control and steppers (oz/in) are you using? If it only happens
                    > > with
                    > >> combined x/y moves then I suspect it's an electrical issue - the
                    > >> steppers aren't getting enough of what they need from the control.
                    > >> Have you run combined x/y moves before without the problem?
                    > >>
                    > >
                    > >
                    > >
                    > >
                    > >
                    > >
                    > > To Post a message, send it to: taigtools@...
                    > >
                    > > To Unsubscribe, send a blank message to: taigtools-unsubscribe@...
                    > >
                    > >
                    > >
                    > > Let the chips fly!
                    > >
                    > > Yahoo! Groups Links
                    > >
                    > >
                    > >
                    > >
                    > >
                    > >
                    > >
                    > >
                    >
                    >--
                    >felice@... is Nicholas Carter and Felice Luftschein. See our
                    >homepage at www.cartertools.com/nfhome.html
                    >
                    >
                    >
                    >To Post a message, send it to: taigtools@...
                    >
                    >To Unsubscribe, send a blank message to: taigtools-unsubscribe@...
                    >
                    >
                    >
                    >Let the chips fly!
                    >
                    >Yahoo! Groups Links
                    >
                    >
                    >
                    >
                  • Nicholas Carter and Felice Luftschein
                    Yeah, it could be anything then...are they working on the power lines? Someone started the dishwasher? Some windows process started running that you didn t
                    Message 9 of 12 , Apr 2, 2006
                    • 0 Attachment
                      Yeah, it could be anything then...are they working on the power lines?
                      Someone started the dishwasher? Some windows process started running
                      that you didn't think existed?

                      Chris Ghent wrote:

                      > I hate intermittent problems.


                      --
                      felice@... is Nicholas Carter and Felice Luftschein. See our
                      homepage at www.cartertools.com/nfhome.html
                    • Rob Ferber
                      Chris, Apologies for the vocabulary - I hate jargon, and try to only use it when it s actually concise rather than merely obfuscation. The resistance of the
                      Message 10 of 12 , Apr 2, 2006
                      • 0 Attachment
                        Chris,

                        Apologies for the vocabulary - I hate jargon, and try to only use it
                        when it's actually concise rather than merely obfuscation.

                        The resistance of the stepper is a funny thing - but most ohm meters
                        can read in the milliohm to ohm range, and all you're really doing is
                        seeing if one winding (the motor has a group of windings, which can be
                        paired up in various ways or addressed individually - the motor will
                        come generally with four, six, or eight leads meaning it's set up for
                        bipolar, unipolar, or any, stepper driver).

                        The stock 200in-oz motors MicroProto ships standard these days came
                        from Lin Engineering, and the wiring chart for them is here:

                        http://www.linengineering.com/site/products/wiringcon.html

                        Even though the 5718-10D motor is a custom winding set (I presume,
                        since it isn't on their standard data sheet), the wiring shouldn't be
                        different in basic layout or you'd need a custom stepper driver to make
                        it go.

                        To test the resistance, just pick the wire pairs - it's safe to
                        probe the end of the cable that plugs into the driver box. Put a test
                        lead in one pin/hole, then measure all the others. You should get
                        infinite (or at least a mega-ohm or so) resistance to some wires, and a
                        single range of values for anything that isn't in that megohm range. For
                        mine, I'm getting 8-10 ohms for a winding, and 5 to 10 Megohms for the
                        others (that would be the resistance of my hand holding the probe, most
                        likely). There are six wires.

                        Sound - this is a great reality check when I'm not certain something
                        is really there, or if it's a physical realm problem or a software
                        problem. If there is a physical cause, then there should be sound
                        differences. Your ear may or may not pick up the changes, but basically
                        you are looking for a spectral line (audio) that appears and disappears
                        with the problem. If there is one way that the problem is easily
                        reproduced, that spectrum should be different from the "normal" ones.
                        This is also a great trick to identify which tire is out of balance or
                        otherwise needs help when driving... put four cheap mikes on the
                        suspension and go for a drive with some cheap recording devices.

                        A free trialware spectrum package is available for Windows at:

                        http://www.visualizationsoftware.com

                        There are many more, this is just one that works well for what I'm
                        doing.

                        NOTE - I have no commercial involvement with either of these
                        companies. These links are provided for information only.

                        Hope this helps. Good luck!

                        -- Rob Ferber
                        rferber@...



                        Chris Ghent wrote:

                        >Rob,
                        >
                        >well, you certainly sent me to the dictionary. I'm looking for a chance
                        >to drop anisotropic and henry into a conversation. Seriously, how would
                        >I check the resistance of a stepper..?
                        >
                        >I'm a fair way yet from checking the sound spectrum, but if it gets to
                        >that what would you be looking for in the spectrum..?
                        >
                        >Chris
                        >
                        >
                        >
                        >> From: Rob Ferber <rferber@...>
                        >>
                        >> 1. Has the resistance (or inductance if you have a micro-henry
                        >>meter) of any of the windings on the stepper changed (are they all the
                        >>same, nearly, or is one out of line)?
                        >>
                        >> 2. If it involves motion in a specific sense, then perhaps this is
                        >>an anisotropic chatter. If you epoxy a cheap microphone (piezo or
                        >>electret) to a chunk of metal and then bolt that to the table, run a
                        >>spectrum on the sound as you
                        >>move the table. I found an anisotropic chatter in mine that way, though
                        >>I still don't know what is causing it.
                        >>
                        >>
                        >>
                      • Chris Ghent
                        Rob, well, you certainly sent me to the dictionary. I m looking for a chance to drop anisotropic and henry into a conversation. Seriously, how would I check
                        Message 11 of 12 , Apr 3, 2006
                        • 0 Attachment
                          Rob,

                          well, you certainly sent me to the dictionary. I'm looking for a chance
                          to drop anisotropic and henry into a conversation. Seriously, how would
                          I check the resistance of a stepper..?

                          I'm a fair way yet from checking the sound spectrum, but if it gets to
                          that what would you be looking for in the spectrum..?

                          Chris

                          > From: Rob Ferber <rferber@...>
                          >
                          > 1. Has the resistance (or inductance if you have a micro-henry
                          >meter) of any of the windings on the stepper changed (are they all the
                          >same, nearly, or is one out of line)?
                          >
                          > 2. If it involves motion in a specific sense, then perhaps this is
                          >an anisotropic chatter. If you epoxy a cheap microphone (piezo or
                          >electret) to a chunk of metal and then bolt that to the table, run a
                          >spectrum on the sound as you
                          >move the table. I found an anisotropic chatter in mine that way, though
                          >I still don't know what is causing it.
                          >
                          >
                        • Chris Ghent
                          ... Steve thanks, the tuning, such as is possible in MPS2003, is conservatively set and has not changed in a year. I will experiment. ... Its the turnkey Taig
                          Message 12 of 12 , Apr 3, 2006
                          • 0 Attachment
                            > From: Steve Blackmore <steve@...>
                            >
                            >Hi Nick - got to agree with you here. Mach3 often shows this until the
                            >motor tuning is set correctly. You can jog any one axis at a particular
                            >speed and all seems well until combined moves, then one or more axis
                            >will stall.
                            >
                            >

                            Steve

                            thanks, the tuning, such as is possible in MPS2003, is conservatively
                            set and has not changed in a year. I will experiment.

                            >Usually just a simple fix, reduce acceleration rate and max velocity
                            >slightly.
                            >
                            >The only other two common reasons are, insufficient power available and
                            >noise.
                            >
                            >Power supply should be able to supply 2/3rds of the rated amperage per
                            >axis, so three 4A motors need an 8A supply.
                            >
                            >
                            Its the turnkey Taig power setup. Not to say it hasn't developed a fault
                            I suppose.

                            >Noise - Stepper cables should be screened and grounded at control box
                            >end only and not bundled with any power cables.
                            >
                            I will check for cables lying close and parallel. This is one thing that
                            could easily have changed recently.

                            To make things more difficult the problem seems to be intermittent. I
                            changed the cutting paths on the job it initially showed up on to omit
                            the move where it happened and it ran OK, even though there are plenty
                            of other moves in roughly the same direction. I need to re-run it with
                            the old paths and with the test hexagon I created to see if it happens
                            again. I'll do that today.

                            I hate intermittent problems.

                            Chris
                          Your message has been successfully submitted and would be delivered to recipients shortly.