I remember it, and I don’t think this is it, but here’s a link anyway!
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Finally have Pi4 → Octopus v1.1 → EBB36 successfully communicating via Klipper/CanBoot over CANBus. Learnt a bunch about CANBus, 'bit trial by fire, had to buy a 2nd EBB36… Still waiting for a board killer badge 
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That’s a great step forward!
Can you document the final setup you have?
I can’t wait to see your printer running with that setup.
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Will do, when ‘done’ enough to claim a serial number.
For now, have started uploading backup/snapshots of my (inprogress) Klipper printer.cfg to github.
23-05-26 Edit: Bought BIQU EBB36 incorrectly thinking that the version with Max31865 onboard provides more accurate, reliable, stable thermostat readings. Sounds great right?
I was wrong, ended up burning time on config/setup because Max31865 isn’t compatible/needed for the NTC based thermistor inside the BIQU H2 V2S Revo’s hotend. Full details in…
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Worked through misc CANBus and Klipper setup/wiring issues. Belted, powered up and zipping around…
Intentionally leaving nozzle and PEI plate off until I understand z_tilt and mesh calibration settings better.
Still figuring out Klipper z_tilt settings and behavior. Tilt adjustment ends up making things worse, maybe I need to negate/flip direction a setting somewhere. Suggestions appreciated!
[z_tilt] #AZA doc @ https://www.klipper3d.org/Config_Reference.html?h=pixel#z_tilt
z_positions: # Pivot Points
-20,27
135, 303
292, 27
#center_Y186
points:
35, 35
135, 245
245, 35
speed: 100
horizontal_move_z: 10
retries: 10
retry_tolerance: 0.005
Technically, think I can claim a serial number as soon as it squirts hot plastic?
Edit: Chris Riley “Klipper - PID Tune - Dial In Your Printer - Chris’s Basement - 2022” helped me tune the Heater_Bed and PID based Extruder/HeaterBed temperature control settings.
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That’s what Ryan said in the serial number post LOL. Printer is looking good! Hopefully I can get past all my self inflicted issues soon LOL
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I have no idea about klipper but marlin has a sort of PID style gain for it’s leveling estimates, or you can do the coordinates of the mount points. We use the gains and if you are a bit too high it gets worse with each level. So I would say either your mount coordinates are off (using the screw locations for the mount plate, not the rail correct?), or your gains are too high.
I hope that helps at all?
I have some klipper stuff ready to go plug in but have not done much but look at it running and glanced at a config.
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Missing space?
-20, 27
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@gpagnozzi @probrwr and any other MP3DP v3/V4 folks using Klipper.
Are you using z_tilt and/or Bed Mesh to probe/level/calibrate your beds before printing?
Curious if z_tilt works for others. Currently digging thru klipper code tracing/debugging z_tilt, so feels like I must be missing something simple. Cheers!
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Z-Tilt on every print.
And call the saved “ Default “ bed mesh.
Once you do the initial setup, z-tilt and save the bed mesh, you don’t need to do bed mesh before every print. Just the z-tilt.
I’m not home to post my current print.cfg but if you look at the one I posted couple months back you can see that start print section call for the z-tilt and the saved bed mesh.
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Nice! Thanks for the info @gpagnozzi, really appreciate confirmation that [z_tilt] is expected to work.
Your post helped me take another look at my setup and wiring again… Turns out I’d messed up the wiring and plugged one of the steppers into motor2_2 
, instead of skipping, similar to what we do for SKR1.2 Pro.
Fixed and finally have z_tilt working now Here’s the stepper wiring that’s working for me…
Seems to take z-tilt 6 attempts to satisfy the retry_tolerance: 0.005 value. Am double checking distances/dimensions of my pivot points to see if that helps. Also moving probe positions as close as possible to pivot points should help.
Even so, I (a Klipper Noob) don’t understand why 0.005 tolerance is needed given the 0.645mm variance observed for my Alu plate. Measured at room temp, no PEI/magnetic layer yet, bought from amzn. Probably not Cast Alu, which I learned would have been more stable during hot-cold cycles. I may also have warped the plate further when cutting down to size with angle grinder. Am still learning what mesh variance most people find acceptable?
Looking at ways to speed up since z-tilt is needed before each print. e.g. Sleep intervals between probe readings seem unnecessarily long (~1s), looking into that too…
Am loosening retry_tolerance: to 0.04 for now until I learn better, and/or someone informs me? Tolerance of 0.04 is helping z-tilt process complete faster with just ~2 attempts.
Cheers!
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Z2 port should have jumpers it is wired in series. It should not work without them.
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0.04mm across a 250mm bed is very good in my opinion. Make sure to let the bed heat soak for a few minutes to stabilize beofre leveling, make sure it has a bit of room to grow and shrink.
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Thanks Ryan, currently heating the bed 60C for ~10mins. Will then z-tilt and mesh calibrate again. Curious to see how much warp occurs…
Update: Getting similar result with or without heat. Don’t know what kind of tolerances others are working to? Guessing high/low spots are due to mix of Alu plate, gantry, surrounding frame, other factors…
Ideally, within reason, I wouldn’t care about the cause, providing the cause and result were consistent, and could be compensated for… Maybe pouring/printing a very thin leveling layer between the Alu and the PEI’s adhesive magnetic layer would help smooth out. “Bed shim generator”, bad idea, or been done already? Briefly thought about using my LR3 to surface Alu plate, but doubtful on accuracy, also, Alu plate may not be most significant cause.
Update #2: Dug around, looks like most people would be happy with measured variance of ~0.3mm or smaller. Some notes and links to things people explored :
- Ryan bed map, ~0.2mm, 200x200, 5x5pts Repeat V2? - #50 by vicious1
- SupraGuy bed map, ~0.25mm, 200x200, 5x5pts MP3DP V4 build PLOG - #68 by SupraGuy
- MattMed bed maps
- v3 ~1.05mm, 200x200, 5x5pts Matt's MP3DP Repeat Build - #132 by MattMed
- v4 ~1.93mm, 200x200, 5x5pts Matt's MP3DP Repeat Build - #244 by MattMed
- Jonathjon bed map, ~2mm, 300x300m, 5x5pts MP3DP V4 Build - #597 by Jonathjon
Update #3: Tried adjusting rails/gantry, getting pivot points close to 0 variance, but the rear loose corners are way off (rear left corner low, rear right corner high). Getting overall Meh variance of ~0.6mm.
Will be using calibrated mesh profiles during prints to reduce impact of bed variance. However… Will probably try out Ryan’s/someone’s suggestion to reduce variance using Blue Tape and/or Kapton Tape as shims. Will add patch work of tape on magnetic layer, under the PEI coated spring metal.
Update #4: Tried z-tilt with 4 corner probe points instead of 3 near the pivot points. Relaxed tolerance as well. Goal was to ensure twisted Alu plate corners are considered by z-tilt, and split the difference finding an orientation that results mesh calibration finding least overall variance. Doing this ended up better variance of ~0.37mm instead Meh ~0.645. Seems good enough to me. Suggestions appreciated, but planning to move onto next step…
Was using [z_tilt] with 3 probe points near Z post pivots…
points: 25, 55
150, 240
245, 55
Changing to 4 probe points with lower z-tilt tolerance resulted in better overall variance.
[z_tilt] #AZA https://www.klipper3d.org/Config_Reference.html?h=pixel#z_tilt
z_positions: -20, 27
135, 303
292, 27
points: 25, 55
25, 240
245, 240
245, 55
speed: 150
horizontal_move_z: 10
retries: 10
retry_tolerance: 0.1 # was 0.04, default 0.005
Pending…
Cheers!
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While trying to minimize bed variance… Made a simple shim to help keep linear rails parallel to extrusion. Assuming extrusion is straight and framed accurately… My thinking was this’d help (marginally) limit variance from being contributed by avoiding skewed linear rails.
shim-lip-4mm.zip (19.7 KB)
Spent some time adjusting the belt tension to try and square the gantry, still doesn’t look/feel right to me, will keep tinkering…
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I have a rail aligner piece in the file stack. What isn’t feeling right?
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This is what I used when i put mine together and it worked well.
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Was curious about impact of PEI on height variance while reading Jonathan’s topic. So, jankily temporarily taped PEI and magnetic layer to Alu plate…
Used 4 point probing for z-tilt (instead of 3, details provided in earlier post), to help split the difference in my minor twisted setup…
Not seeing much difference relative to previous mesh calibrations.
Measured extrusion diagonals between corners, looked the same to me using a regular mm based tape measure. Double checked extrusion is straight too. All looks good enough to me, leaving things as is and moving on. Hope this info helps someone.
Longer term, after seeing Prusa XL at RMRRF, am curious whether linear rails on top of the extrusion would enable easier shimming/adjustments of linear rails to easily compensate for skewed/twisted frame cuts/assembly inaccuracies? Could gain additional X width too, but maybe that approach would introduce other motion challenges?
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That just moves the adjustments to a different plane.
Going to the top moves everything related to XY, that also drags the Z up as well. From messing with it I did not see any advantages, unless I built a mostly metal version.
I am not really sure how I feel about the printers. For the number of builds out there, there seem to be a lot of struggles. It takes me a while to get mine dialed in but I am shooting for pretty extreme accuracy.
I am wondering if my version is fit for a wide release like this. I have nothing to compare it to, but the feedback seems to be 50/50 right now.
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