AutoBim is a simple bed tramming utility for OctoPrint using ABL. Tramming is the process of making sure your bed is as parallel to your printer's X axis as possible. Or, put simply:
Tilted Bed + Tramming = Parallel Bed
The plugin adds a single button to OctoPrint's navbar, because that's all it needs. When the button is clicked, a
combination of GCodes G0
, G28
, G30
, M117
and a bit of message parsing is used to create something like
this (link to YouTube). Jump to 3:10 if it didn't already.
This functionality seems to be part of bugfix-2.0.x
branch at the time of writing, i.e. see
here
So you may want to check out that before using this plugin.
Yes, but it really shouldn't. Imho ABL should be used for correcting irregularities in bed surface (warps, bumps, etc.) and for having the same distance to the bed on every print (think different beds, different bed temps, etc.). Tilted beds should be dealt with in hardware, not in software.
Sure, but where is the fun in that?
I think that depends on the method, and even more on how good you are at your method. It may, it may not.
- OctoPrint (duh)
- ABL probe, such as BLTouch
- Marlin firmware with support for
G30
- Single Z-Probe- Send
G30 X30 Y30
over OctoPrints Terminal. Make sure to home the printer before you do.
- Send
M117
- Set LCD Message- Send
M117 Hello World
over OctoPrints Terminal and look forHello World
on the printer's screen
- Send
Install via the bundled Plugin Manager or manually using this URL:
https://github.com/j-be/AutoBim/archive/master.zip
Hint: Keep your hands away from the printer whenever possible. This not only reduces the risk of your hand colliding with the knob (and thus putting it out of level again) because the printer suddenly moves. It also seems to increase measurement accuracy, at least of my BL Touch. So: wait, adjust, hands off, wait, adjust, hands off, ...
Marlin needs to know where your probe is relative to the nozzle. This position is known as XYZ Probe Offset. While pretty much everybody will have Z offset calibrated, X and Y are sometimes neglected. They shouldn't though, they are important, too.
To check, send the following commands to the printer (e.g. via OctoPrint's Terminal) or do it any other way you are comfortable doing it:
G28
; Home the printerG0 Z20
; Move the nozzle up so it is a safe distance from the bed. I consider 20mm to be safe, feel free to use a different value.G0 X30 Y30
; Probe X=30, Y=30- Mark the exact spot below the nozzle. This can e.g. be done be putting a piece of paper on the bed and marking the spot there. If you have a glass bed and a marker you know you can remove without residue, use that. Feel free to lower the nozzle a little bit if that makes it easier.
G30 X30 Y30
; Probe the point. The printer should now move the probe to the point we marked in the step above.
If it probed the point your printer is correctly set up. If not, check out M851 in Marlin documentation for further information on the topic.
Defaults are for an Ender 3 sized printer and a BLTouch. You can configure:
- Invert arrows on display, e.g. for inverse screw threads on the adjustment screws
- Default:
Off
- Default:
- Enable/Disable multi-pass (i.e. go on until a full round measures ok)
- Default:
On
- Default:
- Accuracy threshold
- Default:
0.01
- Default:
- Unified Bed Leveling - Enable this if your firmware was compiled with UBL
- Default:
False
- Default:
- Delay between corners - Wait the given amount of seconds before moving to next corner
- Default:
0.0
- Default:
- Points to probe
- Default:
(30, 30), (200, 30), (200, 200), (30, 200)
(Ender 3) - Note: These coordinates refer to probe position, while most other coordinates (e.g. what is displayed on screen)
refer to nozzle position. Try to use the points exactly above the set screws if that is possible (see Works fine
on the first corner, display says
ok. moving to next
but nothing happens below) or get as close as possible.
- Default:
- Show button in Navbar
- Default:
True
- Default:
Planned are (ordered by assumed priority):
- Allow for a different amount of probe points
- Pattern for
G30
response parsing
Since there are quite some unknowns in the process, here a list of what should happen when you click the button in the navbar:
Step | You | Message on Display | |
---|---|---|---|
1 | Home | wait... |
|
2 | Raise to Z=20 | wait... |
|
3 | Go to corner point and probe | wait... |
|
4 | Display difference and direction to rotate the knob | Turn the leveling wheel/knob/lever | e.g. 0.16 >>> (adjust) for 0.16mm to high, turn right (i.e. counter-clockwise) to correct |
5 | Printer goes on probing until the difference is within threshold | Turn the leveling wheel/knob/lever | e.g. -0.01 <<< (adjust) for 0.01mm to low, turn left (i.e. clockwise) to correct |
6 | Measurement is within threshold | ok. moving to next |
|
6.5 | If "Delay before moving to next corner" is set, wait for that amount | ok. moving to next |
|
7 | If full round completed without a difference, we are done | done. |
|
Else, go to Step 3 for the next corner | ok. moving to next |
If that is not what happens look at Troubleshooting below. If that doesn't help consider opening an issue detailing where it goes wrong, how, and (if you have a suspicion) why.
Works fine on the first (or first and second corner), display says ok. moving to next
but nothing happens
Most likely that means the printer cannot reach the point set in Points to probe because it would need move beyond what it considers to be its moving range. This is a feature known as "software endstops" in Marlin.
For your X axis, the most likely issue is X_MAX_POS
set in the firmware. For most builds this will default to
X_BED_SIZE
, but on most printers it should be possible to raise this a little bit, e.g. on my Ender 3 Pro this can be
set to 245 as it can easily move the nozzle 10mm left of the bed. It won't ever print there - that's what X_BED_SIZE
is for - but moving there temporarily, e.g. for probing, is fine. The same applies to Y
, i.e. on an Ender 3 Pro you
can set it to 240.
Another reason could be, that PROBING_MARGIN
in your firmware is set to something, that makes no sense. E.g. I heard
Ender 6 stock firmware seems to set Y_BED_SIZE
to 260, the bed is 290 in depth, and Creality - in there infinite
wisdom - still seems to have decided to apply an additional PROBING_MARGIN
of 30. This effectively makes 230 the
maximum usable Y coordinate for probing.
As to why the plugin doesn't react to this condition: At least on my machine there is no indication on the log, that the
printer can't do what it was told. I get an ok
, which I find misleading at least. If you have an idea on how to catch
this error, which doesn't involve timing the response time on a G30
, feel free to open an issue for that.
I found the following sequence in OctoPrint's Terminal to work well. Assuming you'd like to find the maximum Y
value:
G28
; Home the printerG0 Z20
; Raise hotend to Z=20 to avoid collisions while movingG30 X30 Y195
; Tell printer to probe X=30 Y=195- If printer doesn't move try
G30 X30 Y190
- If printer moves try
G30 X30 Y192
- If printer doesn't move try
- ... and so on, until you found the maximum Y value
- Take that value and use it as the upper Y value in Points to probe
Also, please check out if #2 sounds like a good solution to the problem, and
give it a thumbs up or thumbs down respectively. Please don't comment to +1
, I'd appreciate it.
As a last resort and if you have no other possibility you may consider temporarily disabling endstops in Marlin
using the M121
command. Doing that could cause serious damage to your bed or printer, so once you did that always
have your hand on the power switch - just in case. When you are done, be sure to reenable the endstops using
M120
. You have been warned!
This most probably means that your printer returns the measured coordinates in a format different than mine does. To
check this, please go to OctoPrint's Terminal and enter a G30
(make sure you homed before and raised your hotend a
little bit to avoid collisions). I'd recommend the following sequence:
G28
; Home the printerG0 Z20
; Move the nozzle up so it is a safe distance from the bed. I consider 20mm to be safe, feel free to use a different value.G30 X30 Y30
; Probe X=30, Y=30
On my printer I see the following (irrelevant stuff and Recv: echo:busy: processing
removed for brevity):
Send: G28
[...]
Recv: X:159.00 Y:122.00 Z:12.03 E:0.00 Count X:12720 Y:9760 Z:4812
Recv: ok
[...]
Send: G0 Z20
Recv: ok
[...]
Send: G30 X30 Y30
[...]
Recv: Bed X: 30.00 Y: 30.00 Z: 0.00
Recv: X:72.00 Y:35.00 Z:12.03 E:0.00 Count X:5760 Y:2800 Z:4812
Recv: ok
I am most interested in if there is a line like the Recv: Bed X: 30.00 Y: 30.00 Z: 0.00
above. If yours contains the
same information, but looks different, let me know, I'm happy to add that as a setting.
I can't seem to get a full round complete - there is always one point, that is +/-0.01 off. Is something broken?
Most probably not. By using 0.01mm as threshold we are close to the BLTouch's tolerance, which means that there is
already a little luck involved, too. It can take some 5, 6 rounds (and more) with only some corners off by +/-0.01 until
a full run completes. If you don't care that much, you can always raise Accuracy threshold in the settings. Note, that
Marlin (at least my build does this) reports only 2 decimal digits, so a setting of 0.011
will have the same effect as
0.02
. At the time of writing, Marlin's presumably equivalent LEVEL_CORNERS_USE_PROBE
feature uses 0.1
as tolernace
by default (see here.
Additionally, keep in mind that changing one of the corners may affect other corners as well - which is why the plugin does the multi-pass in the first place. The closer your probe points are to the set screws, the less the influence. So you may want to spend a little time getting those right.
This means your firmware was compiled with Unified Bed Leveling.
Open the plugin settings and check the UBL (Unified Bed Leveling)
checkbox.
Unfortunately, all parameters referring to probing seem to be hardcoded in Marlin and are not readable via GCode. It
seems, for example, the plugin is not able to override the amount the hotend is raised after probing (I think that
should be LEVEL_CORNERS_Z_HOP
, but I'm not even sure on that), which would be great to save some time.
Also, there seems to be no way to read stuff like TRAMMING_POINT_XY
and TRAMMING_SCREW_THREAD
, so I need to add them
as settings.
That said: I am far from being an expert on Marlin. If you know a way to set them via G-Code, please open an issue detailing on how one can do that and I will definitely have a look at it.
This plugin is meant to help with bed tramming. I am from Vienna, and trams in
Vienna are called "Bim" (like "bin" as in "trash bin", just with an m
instead of the n
).
Credit goes to the following projects for being there and letting me look at and copy their code:
- https://github.com/jneilliii/OctoPrint-BedLevelVisualizer
- https://github.com/marian42/octoprint-preheat
Make sure to check them out, and don't forget:
"Toss a coin to your developers, o valley of plenty, o valley of plenty..."