Manual Mesh Bed Leveling no z endstop July 03, 2017 11:19AM |
Registered: 7 years ago Posts: 4 |
Re: Manual Mesh Bed Leveling no z endstop September 26, 2017 12:33PM |
Registered: 6 years ago Posts: 26 |
Re: Manual Mesh Bed Leveling no z endstop September 26, 2017 01:23PM |
Registered: 6 years ago Posts: 262 |
Re: Manual Mesh Bed Leveling no z endstop September 26, 2017 02:21PM |
Registered: 6 years ago Posts: 26 |
+<-- Endstop | | | Bed -------------Z^
Re: Manual Mesh Bed Leveling no z endstop September 26, 2017 05:39PM |
Registered: 6 years ago Posts: 262 |
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RepMike
To me, it was contradictory to have a Z endstop and to do Manual (Mesh) Bed Leveling, but this guide speaks of a metal arm (seek for those two words on that page) and THAT little travel distance of the metal arm is the +/- area of adjustment, so in the end it worked for me. I think I will replace that with an opto endstop, that will allow me better adjustment, I think. So that's my experience so far with this. And true, @JustSumGuy, how in the world would Marlin have an opportunity to sense the bed without an Endstop?
Other idea: Would manual bed leveling also work by placing the Z axis' only endstop on the high end of the Z axis and then go negative from there in order to find the bed at a defined distance?
+<-- Endstop | | | Bed -------------Z^
Re: Manual Mesh Bed Leveling no z endstop September 26, 2017 07:53PM |
Registered: 9 years ago Posts: 978 |
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JustSumGuy
I would avoid that, in case of a skipped step or some other malfunction you could drive your head into the bed
Re: Manual Mesh Bed Leveling no z endstop September 27, 2017 11:15AM |
Registered: 6 years ago Posts: 262 |
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frankvdh
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JustSumGuy
I would avoid that, in case of a skipped step or some other malfunction you could drive your head into the bed
Practically every 3D printer runs on the assumption that it won't skip steps. Once printing starts, the endstops aren't checked again. So if you can't assume that every step will work correctly, you can't reliably print at all. In which case, it doesn't matter if the endstop is at the top or bottom. Typically, Delta printers have endstops at the top of each tower (plus perhaps a bed-detection probe).
Mesh bed leveling really isn't "manual"... it uses the Z end-stop (which must be triggered when the nozzle touches the bed) to probe the bed around a grid. If you use the G29 command without a probe, the nozzle will crash into the bed.
You *can* print without using a Z endstop. The printer assumes that at power-on, it is at Z=0. So use a piece of paper to set the Z height, then turn the printer on and you're good to go. But if you use Z homing (X & Y are OK) or bed levelling, the nozzle will crash into the bed.
What I do is to have the Z endstop always on. This way, an accidental home won't crash into the bed. When I want to set the Z height, I do a Z home, then manually wind the head down to grip a piece of paper.