Z-Axis Resolution May 01, 2021 02:45AM |
Registered: 3 years ago Posts: 5 |
Re: Z-Axis Resolution May 01, 2021 04:30AM |
Registered: 3 years ago Posts: 92 |
Re: Z-Axis Resolution May 01, 2021 09:29AM |
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Re: Z-Axis Resolution May 03, 2021 01:33PM |
Registered: 3 years ago Posts: 5 |
That makes a lot of sense, and is the kind of design principles I was expecting to find when I dug in. I like your analysis of "how we got where we are", mostly because it sounds pretty much the same as my line of thinking.Quote
dekutree64
Personally I prefer T8x2 leadscrews because you get 0.01mm full steps, which gives full torque to the target position, fast movement, no risk of backdriving, and no numerical problems.
That is precisely my goal. I've spent a buncha hours now reading over various builds/designs/blogs, and I'm in awe of the work and thought you've put into your machines and, just as importantly, the blog posts you've written and published that document your design concepts and builds. Thank you for doing that - there'll be a lot of your DNA in whatever I end up putting together.Quote
the_digital_dentist
When you build the new printer, it is possible to build it so that it won't need any tuning and tweaking before you print
I fully agree, but isn't that only true if you've homed the bed at a whole-step point on the Z-axis stepper? I mean, if I home my Anet A6 and the Z stepper ends up at e.g. microstep 11, every layer I advance still ends up with the stepper at a microstep 11. dekutree64's example points out that if your design only allows full step positions, and those full steps are sufficiently small, the microstep 11 problem simply vanishes and you get full advantage of always being at a full step along with plenty of resolution for whatever needs doing.Quote
the_digital_dentist
for maximum print quality, you usually want the layer thickness to be a multiple of the Z axis whole-step resolution.
Re: Z-Axis Resolution May 03, 2021 02:59PM |
Registered: 11 years ago Posts: 5,780 |
Re: Z-Axis Resolution May 03, 2021 04:20PM |
Registered: 3 years ago Posts: 5 |
Quote
the_digital_dentist
Have you heard a motor slewing the Z axis in full steps? Let's just say it has low spousal acceptance factor.
Re: Z-Axis Resolution May 03, 2021 05:22PM |
Registered: 3 years ago Posts: 92 |
Re: Z-Axis Resolution May 03, 2021 10:55PM |
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Re: Z-Axis Resolution May 04, 2021 12:42AM |
Registered: 3 years ago Posts: 92 |
Right, of course the print should be removed from the bed before running the Z0 program. That's why it needs to be a separate file on the SD card rather than simply included at the end of every gcode file. The point is that once the printer has been homed and printed something, it knows where home is so you can safely move back at high speed. The usual homing operation is waiting for the endstop signal, so it has to move slow and careful since it can't decelerate in advance.Quote
the_digital_dentist
Motors are only quiet if you use microstepping, Trinamic drivers will be as noisy as any other if you're driving the motor in full steps.
Homing the Z axis at the end of a print is potentially disastrous. You might want to home X and Y to get the print away from the extruder, but leave Z where it is until after the print is removed from the bed. There's no need for a separate gcode file to home Z. Just select homing from the LCD panel, web control, or Pronterface console, etc., depending on how you control your printer.
Re: Z-Axis Resolution May 04, 2021 02:05AM |
Registered: 3 years ago Posts: 5 |
Quote
dekutree64
I'm not sure if there's any way for the firmware to know whether it's on a full step position or not.
Re: Z-Axis Resolution May 04, 2021 08:13AM |
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Re: Z-Axis Resolution May 04, 2021 03:35PM |
Registered: 3 years ago Posts: 92 |
Re: Z-Axis Resolution May 04, 2021 05:41PM |
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Re: Z-Axis Resolution May 04, 2021 07:00PM |
Registered: 3 years ago Posts: 92 |