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

A couple of Noob questions - Spindle speed/ M50 plus X/Y location errors.

Expand Messages
  • milton_d1
    1) I hooked up a spindle disc & optical sensor via a C3 board from CNC4PC through pin 10 and all seems to be functioning properly. After an earlier quick scan
    Message 1 of 4 , May 3, 2011
    • 0 Attachment
      1) I hooked up a spindle disc & optical sensor via a C3 board from CNC4PC through pin 10 and all seems to be functioning properly. After an earlier quick scan of the manual, I was thinking I would be able to use it to read spindle speed and display it like a tach in TCNC via an M50 command in the MDI screen but it looks like I was wrong.

      I eventually want to install a Homann DigiSpeed XL to control the spindle speed but recent hobby-budget cutbacks won't allow it for quite some time. Is there any thing else I can use the speed sensor for using TCNC? I'd like to be able to accurately read and adjust the spindle speed manually before starting a cut. Forgive my noob-ness; I am somewhat trainable.:)

      2) When I tyoe in simple G01 commands just playing around in X or Y, (G01X.1F5 or G01Y.1F5 ) TCNC displays .099997 on Y and .099984 on X. If I return to zero by typing G01X0, it displays zero OK but consistently shows the odd numbers after commanding it to go to an even number location. Obviously that tiny error doesn't make any difference in a real world part but I was curious if I've set something up wrong.

      Thanks for looking!
    • milton_d1
      ... Update: Well, I said I was a noob didn t I? I found a few minutes tonight to play with it some more and found that I hadn t Enabled pin 10 as the
      Message 2 of 4 , May 9, 2011
      • 0 Attachment
        --- In turbocnc@yahoogroups.com, "milton_d1" <mdickey@...> wrote:
        >
        > 1) I hooked up a spindle disc & optical sensor via a C3 board from CNC4PC through pin 10 and all seems to be functioning properly. After an earlier quick scan of the manual, I was thinking I would be able to use it to read spindle speed and display it like a tach in TCNC via an M50 command in the MDI screen but it looks like I was wrong.
        >
        > I eventually want to install a Homann DigiSpeed XL to control the spindle speed but recent hobby-budget cutbacks won't allow it for quite some time. Is there any thing else I can use the speed sensor for using TCNC? I'd like to be able to accurately read and adjust the spindle speed manually before starting a cut. Forgive my noob-ness; I am somewhat trainable.:)
        >
        > 2) When I tyoe in simple G01 commands just playing around in X or Y, (G01X.1F5 or G01Y.1F5 ) TCNC displays .099997 on Y and .099984 on X. If I return to zero by typing G01X0, it displays zero OK but consistently shows the odd numbers after commanding it to go to an even number location. Obviously that tiny error doesn't make any difference in a real world part but I was curious if I've set something up wrong.
        >
        > Thanks for looking!
        >

        Update: Well, I said I was a noob didn't I? I found a few minutes tonight to play with it some more and found that I hadn't "Enabled" pin 10 as the spindle encoder input. DUHH! M50 now works perfectly and gives a very accurate speed readout...after an M03 of course. Now onward to the next noobie challange.:)
      • dkowalcz2000
        Milton: I meant to post on this the other day - the most likely reason for this is that the step size doesn t allow reaching the commanded position exactly.
        Message 3 of 4 , May 11, 2011
        • 0 Attachment
          Milton:

          I meant to post on this the other day - the most likely reason for this is that the step size doesn't allow reaching the commanded position exactly.

          Internally, the commanded and "actual machine" positions are stored separately so that incremental moves and commands that depend on current position (i.e., circles) are executed correctly while ensuring that no error accumulates. The display shows actual rather than commanded.

          I guess I should eventually make that configurable - there are some folks that have condemned the software over what is essentially a misunderstanding.

          Good luck with your projects!

          Yours,
          Dave Kowalczyk
          Author, TurboCNC
          http://www.dakeng.com

          --- In turbocnc@yahoogroups.com, "milton_d1" <mdickey@...> wrote:
          >
          > > 2) When I tyoe in simple G01 commands just playing around in X or Y, (G01X.1F5 or G01Y.1F5 ) TCNC displays .099997 on Y and .099984 on X. If I return to zero by typing G01X0, it displays zero OK but consistently shows the odd numbers after commanding it to go to an even number location. Obviously that tiny error doesn't make any difference in a real world part but I was curious if I've set something up wrong.
          > >
          > > Thanks for looking!
          > >
        • milton_d1
          ... Thanks Dave, much appreciated!
          Message 4 of 4 , May 11, 2011
          • 0 Attachment
            --- In turbocnc@yahoogroups.com, "dkowalcz2000" <dkowalcz@...> wrote:
            >
            > Milton:
            >
            > I meant to post on this the other day - the most likely reason for this is that the step size doesn't allow reaching the commanded position exactly.
            >
            > Internally, the commanded and "actual machine" positions are stored separately so that incremental moves and commands that depend on current position (i.e., circles) are executed correctly while ensuring that no error accumulates. The display shows actual rather than commanded.
            >
            > I guess I should eventually make that configurable - there are some folks that have condemned the software over what is essentially a misunderstanding.
            >
            > Good luck with your projects!
            >
            > Yours,
            > Dave Kowalczyk
            > Author, TurboCNC
            > http://www.dakeng.com
            >
            Thanks Dave, much appreciated!
          Your message has been successfully submitted and would be delivered to recipients shortly.