ellensp
commented
1 year ago Cannot be in firmware. Cannot tell that if the Z height is printing layer N or just jumped to layer N with something like a Z,hop.
Then there is non planer slicing, Where the moves are in x,y and z a lot. (not just Z on layers)
In-fact I think whom ever suggested this should be firmware is pulling your leg. Or has no idea what they are talking about.
This needs to be done at slicing time.
In reality if your losing steps, this is nothing but a nasty kludge. You need to fix the cause of the lost steps
thisiskeithb
lunartester
github-actions[bot]
Is your feature request related to a problem? Please describe.
Homing X,Y and resetting Absolute Coordinates on X,Y,Z
Are you looking for hardware support?
Creality 32-bit board or any other 32-bit board that supports Marlin and has 5V power for 3-wire optical end stop set up.
Describe the feature you want
Markforged does not use encoders or any error correction nor any closed loop systems in their desktop series, they use optical end stops and their printers home to X,Y every few printing layers. Stratasys does the same thing even with encoders and closed loop systems. I suspect they do a some type of reset on error accumulation with that home X,Y.
It's unclear if they use Absolute or Relative on X,Y,Z....... but that feature is the one that produces consistent results in compensation for any backlash or worn out gantry parts over long haul. Markforged layer seam is fixed position, the end user cannot change it in their slicer, so they know the exact distance from start of each layer to the X,Y,Z end stops, or at least they can reset it every time it homes.
Homing will require a separate wipe as last move before it homes and second retraction tied up to that specific procedure, so even if wipe is not selected in slicer there must be a wipe option for the end user and ability to set wipe distance and ability to set differnt retraction for that homing reset.
What is unclear to me is what is the exact algorithm they use there on error correction, is it just a reset, or something more complex. They use 64-bit beagelbone running on Linux, I want to use Creality 32-bit board.
I was told by Prusa dev team member implementing it in Slicer via gcode or script is not optimal and needs to be done in firmware.
So the main question is, how trivial is it to add this to Marlin. I know it Marlin does a reset on Extruder with each layer change, can we expand this to X,Y,Z with homing and retraction/ wipe option for that homing or at elast the wipe and retraction setting can be changed via Gcode?
The end user must have an option how often or after how many layers they want to reset it with homing.
Cheers.
Additional context
No response