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    Steps per mm keep changing

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    • akhilnexundefined
      akhilnex @theruttmeister
      last edited by

      @theruttmeister said in Steps per mm keep changing:

      You say that your axies are all running that same leadscrew... but your settings don't match that. Your Y and Z match what you say, your X is off.

      @theruttmeister you are right and I forgot to mention past evening that I installed a gear reducer (5:1) to run the heavy Y axis gantry.

      1 Reply Last reply Reply Quote 0
      • Vetiundefined
        Veti
        last edited by

        those are some beefy stepper motors. can you post the specs for them?

        akhilnexundefined 1 Reply Last reply Reply Quote 0
        • akhilnexundefined
          akhilnex @Veti
          last edited by

          @Veti

          NEMA 17: https://www.omc-stepperonline.com/nema-17-bipolar-1-8deg-65ncm-92oz-in-2-1a-3-36v-42x42x60mm-4-wires-it.html

          NEMA 23: https://www.omc-stepperonline.com/nema-23-bipolar-3nm-425oz-in-4-2a-57x57x114mm-4-wires-stepper-motor-cnc.html

          Specification table is on the second tab. I didn't find a torque curve or any performance graph though.

          Vetiundefined 1 Reply Last reply Reply Quote 0
          • Vetiundefined
            Veti @akhilnex
            last edited by

            @akhilnex

            you should aim for about 75% of the rated current.

            so around 3150 for the nema23.

            and stay with x16 with interpolation for now.
            going high puts unnecessary load on the cpu.

            akhilnexundefined 1 Reply Last reply Reply Quote 1
            • akhilnexundefined
              akhilnex @Veti
              last edited by

              @Veti I have made the changes to 16x and the deviation is still present. Although the amount of deviation is slightly different for requested [actual] readouts: 50 [ 48.5 mm], 100 [102 mm], 150 [155 mm], 200 [210 mm], 250 [265 mm], 300 [317.5]. It seems like the pattern changed but the amount exceeding follows a similar trend starting with low deviation and increasing at 2.5 mm increments as the the requested distance goes up.new reprap 16x.PNG config (1).g

              JoergS5undefined 1 Reply Last reply Reply Quote 0
              • JoergS5undefined
                JoergS5 @akhilnex
                last edited by JoergS5

                @akhilnex please be aware that 1:5 gears are often 1:5.18 gears (exactly 1: 5+2/11 = 1: 5.181818). The datasheet will tell you.

                akhilnexundefined 1 Reply Last reply Reply Quote 1
                • akhilnexundefined
                  akhilnex @JoergS5
                  last edited by akhilnex

                  @JoergS5 that's a good point and I think it is true 5:1 planetary reduction gearbox. Here is the link of what I got on Amazon: https://www.amazon.com/dp/B089R8CC1Z/ref=cm_sw_r_cp_apa_fabc_.-m6FbC0RS0XV

                  Seems like with the new settings the x,y,z axis are running quite accurate. However the NEMA 17 extruder steppers are the one causing trouble.

                  JoergS5undefined 1 Reply Last reply Reply Quote 0
                  • fcwiltundefined
                    fcwilt
                    last edited by

                    I used these for my belt driven Z axis conversion.

                    The 5-to-1 is a true 5-to-1.

                    They have a similar "economy" line product which is not.

                    Frederick

                    Printers: a E3D MS/TC setup and a RatRig Hybrid. Using Duet 3 hardware running 3.4.6

                    1 Reply Last reply Reply Quote 0
                    • JoergS5undefined
                      JoergS5
                      last edited by

                      yes, looks like a true 5:1

                      1 Reply Last reply Reply Quote 0
                      • JoergS5undefined
                        JoergS5 @akhilnex
                        last edited by

                        @akhilnex did you check M122 after running the steppers for some time? M122 reports several possible problems, please post the result. (one is hiccups, but also stepper problems, voltage problems etc.).

                        akhilnexundefined 1 Reply Last reply Reply Quote 1
                        • akhilnexundefined
                          akhilnex @JoergS5
                          last edited by

                          @JoergS5 M122
                          === Diagnostics ===
                          RepRapFirmware for Duet 3 MB6HC version 3.1.1 running on Duet 3 MB6HC v1.01 or later (standalone mode)
                          Board ID: 08DJM-956L2-G43S8-6J9D0-3S46Q-9U2GD
                          Used output buffers: 3 of 40 (40 max)
                          === RTOS ===
                          Static ram: 154604
                          Dynamic ram: 162740 of which 20 recycled
                          Exception stack ram used: 376
                          Never used ram: 75476
                          Tasks: NETWORK(ready,356) ETHERNET(blocked,436) HEAT(blocked,1200) CanReceiv(suspended,3820) CanSender(suspended,1488) CanClock(blocked,1424) TMC(blocked,60) MAIN(running,4512) IDLE(ready,76)
                          Owned mutexes:
                          === Platform ===
                          Last reset 00:31:39 ago, cause: software
                          Last software reset at 2020-12-27 10:43, reason: User, spinning module GCodes, available RAM 75476 bytes (slot 3)
                          Software reset code 0x0003 HFSR 0x00000000 CFSR 0x00000000 ICSR 0x0444a000 BFAR 0x00000000 SP 0xffffffff Task MAIN
                          Error status: 4
                          MCU temperature: min 40.6, current 41.1, max 41.5
                          Supply voltage: min 24.0, current 24.1, max 24.2, under voltage events: 0, over voltage events: 0, power good: yes
                          12V rail voltage: min 12.1, current 12.1, max 12.2, under voltage events: 0
                          Driver 0: standstill, reads 20644, writes 14 timeouts 0, SG min/max 0/0
                          Driver 1: standstill, reads 20632, writes 27 timeouts 0, SG min/max 0/81
                          Driver 2: standstill, reads 20645, writes 14 timeouts 0, SG min/max 0/0
                          Driver 3: standstill, reads 20646, writes 14 timeouts 0, SG min/max 0/0
                          Driver 4: standstill, reads 20646, writes 14 timeouts 0, SG min/max 0/0
                          Driver 5: standstill, reads 20634, writes 27 timeouts 0, SG min/max 0/431
                          Date/time: 1970-01-01 00:00:00
                          Slowest loop: 999.77ms; fastest: 0.13ms
                          === Storage ===
                          Free file entries: 10
                          SD card 0 detected, interface speed: 25.0MBytes/sec
                          SD card longest read time 2.8ms, write time 29.6ms, max retries 0
                          === Move ===
                          Hiccups: 0(0), FreeDm: 375, MinFreeDm: 373, MaxWait: 1347113ms
                          Bed compensation in use: none, comp offset 0.000
                          === MainDDARing ===
                          Scheduled moves: 12, completed moves: 12, StepErrors: 0, LaErrors: 0, Underruns: 0, 0 CDDA state: -1
                          === AuxDDARing ===
                          Scheduled moves: 0, completed moves: 0, StepErrors: 0, LaErrors: 0, Underruns: 0, 0 CDDA state: -1
                          === Heat ===
                          Bed heaters = 0 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1, chamberHeaters = -1 -1 -1 -1
                          === GCodes ===
                          Segments left: 0
                          Movement lock held by null
                          HTTP is idle in state(s) 0
                          Telnet is idle in state(s) 0
                          File is idle in state(s) 0
                          USB is idle in state(s) 0
                          Aux is idle in state(s) 0
                          Trigger is idle in state(s) 0
                          Queue is idle in state(s) 0
                          LCD is idle in state(s) 0
                          SBC is idle in state(s) 0
                          Daemon is idle in state(s) 0
                          Aux2 is idle in state(s) 0
                          Autopause is idle in state(s) 0
                          Code queue is empty.
                          === Network ===
                          Slowest loop: 57.01ms; fastest: 0.03ms
                          Responder states: HTTP(0) HTTP(0) HTTP(0) HTTP(0) HTTP(0) HTTP(0) FTP(0) Telnet(0), 0 sessions Telnet(0), 0 sessions
                          HTTP sessions: 1 of 8

                          • Ethernet -
                            State: active
                            Error counts: 0 0 0 0 0
                            Socket states: 5 2 2 2 2 0 0 0
                            === CAN ===
                            Messages sent 7600, longest wait 0ms for type 0
                            === Linux interface ===
                            State: 0, failed transfers: 0
                            Last transfer: 1899941ms ago
                            RX/TX seq numbers: 0/1
                            SPI underruns 0, overruns 0
                            Number of disconnects: 0
                            Buffer RX/TX: 0/0-0
                          JoergS5undefined 1 Reply Last reply Reply Quote 0
                          • akhilnexundefined
                            akhilnex
                            last edited by akhilnex

                            Since X,Y and Z gantries are working fine, I am wondering if the NEMA 17 motors on E0,1,2 that I purchased from stepperonline are faulty. I am thinking about ordering atleast one different brand NEMA 17 and a regular extruder hob gear to check and see if it works any better.

                            theruttmeisterundefined 1 Reply Last reply Reply Quote 0
                            • akhilnexundefined
                              akhilnex
                              last edited by akhilnex

                              Can an issue arise from having NEMA 23 and NEMA 17 running on the same board? Should they all be the same 23s or 17s?

                              A Former User? 1 Reply Last reply Reply Quote 0
                              • A Former User?
                                A Former User @akhilnex
                                last edited by

                                @akhilnex said in Steps per mm keep changing:

                                Can an issue arise from having NEMA 23 and NEMA 17 running on the same board? Should they all be the same 23s or 17s?

                                as long as the individual motors are suited for the drivers then you can mix and match whatever you like. (you'd probably want to have the same specs motor if you run multiple motors in parallel or serial on a single driver)

                                the nema number has more to do with physical dimensions than electrical parameters, so not directly relevant even though physically larger motors usually have lower impedance and higher current ratings.

                                1 Reply Last reply Reply Quote 1
                                • JoergS5undefined
                                  JoergS5 @akhilnex
                                  last edited by JoergS5

                                  @akhilnex M122 looks ok, but only a part of the drivers were used. You can repeat M122 after a longer test again. The short test didn't show problems.

                                  I thought about that maybe your multi extruder causes the difference. Depending on pressure and temperature, the speed could vary.

                                  akhilnexundefined 1 Reply Last reply Reply Quote 1
                                  • akhilnexundefined
                                    akhilnex @JoergS5
                                    last edited by

                                    @JoergS5 I haven't even gotten to the multi extruder yet. Just trying to get the extruder steppers to run correctly.

                                    Once I get accurate reading on the filament movement, my next step will be to pass it through the heated multi-extruder. I guess that's the fun of building random design from scratch as every new step brings a brand new set of challenge! 🙃

                                    JoergS5undefined 1 Reply Last reply Reply Quote 0
                                    • JoergS5undefined
                                      JoergS5 @akhilnex
                                      last edited by JoergS5

                                      @akhilnex If the extruder speed is still wrong, you could try separating the problem into it's possible single problems. The problem could be the stepper speed, the hob nut, hob nut slipping, filament slipping, different diameters of the filament.

                                      I would use the stepper with a normal pulley first and measure the speed and verify that it has the expected speed. You could use a belt and measure the distance. When it's ok, the problem is behind the stepper shaft. If it's wrong, it can be a configuration, electronics with wiring, stepper, shaft problem.

                                      Developing something new is without question an exciting journey for you!

                                      akhilnexundefined 1 Reply Last reply Reply Quote 0
                                      • akhilnexundefined
                                        akhilnex @JoergS5
                                        last edited by

                                        @JoergS5 you are right. I will decouple the motor and test everything separately. I am not sure if slippage is an issue as its running over (+10% approx.) rather then under after calibrating for one distance setting.

                                        1 Reply Last reply Reply Quote 0
                                        • akhilnexundefined
                                          akhilnex
                                          last edited by

                                          Still unsolved: Error stays (2.5mm increase in distance traveled for every 50mm movement) for all steppers on my board:

                                          1. Tried to erase and write firmware and new reprap code files.
                                          2. Tried different steppers, extrusion hob drivers( with and without).
                                          3. Played with speed, current, microsteps (with and without interpolation)

                                          f3ab8f3d-0f66-47a9-a445-90c14b4617a4-image.png

                                          JoergS5undefined 2 Replies Last reply Reply Quote 0
                                          • JoergS5undefined
                                            JoergS5 @akhilnex
                                            last edited by JoergS5

                                            This post is deleted!
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