BL Touch
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So then how do I do the independent leveling?
First, understand the difference between 'bed (plane) levelling' and 'Bed mesh compensation'. Levelling the bed plane to the nozzle is trying to get the bed square to the XY axis, and has to be done mechanically; using the independent levelling takes some of the hassle out of this, by doing it automatically. However, mesh bed compensation is NOT levelling; it's to account for anomalies in the bed, though it can be used to show that the bed (or X axis) is not level.
As you have a 'bed slinger', with bed moving in Y, and X mounted on Z (rather than any other layout eg CoreXY or Cartesian with bed moving in Z, eg Ultimaker), you actually need to do five things to get everything square:
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Build the machine square, so that XY, XZ and YZ linear rails are perpendicular with each other (three degrees of freedom - axis skew), and any dual linear rails (X, Y and Z) are parallel (three more degrees of freedom - rotation around axis). This, in itself, is so important and often overlooked. There are some good videos online.
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Level the X gantry to the frame: you need to do this at least once, so you can reference the bed from the frame.
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Mechanically level the bed to the nozzle: I expect your bed has levelling screws at the corners, so you have to do this manually. There is a method to do this with the Z probe, or you can do this manually by moving the nozzle to various points on the bed and adjusting the bed adjusters, like everybody did in the 'old' days.
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Create a bed mesh to account for anomalies in the bed.
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If printed parts are still not orthogonal (square), see M556, though you've probably not done step 1 right.
You can swap 2 and 3 around, and level the bed to the frame, then level the X axis to the bed, though it's generally more accurate to level the X gantry to the frame.
Steps 1, 2 and 3 should be your initial commissioning, and once done, shouldn't need redoing too often if you don't move the printer. Be aware you really want the printer on something flat, so it doesn't twist the frame. Steps 4 should only need redoing if you're using a different temperature, or you want to check the bed is still level. Step 5 would be if you moved the printer, and didn't want to go back to step 1 again!
Then, each time you turn the printer on:
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With the bed square to the frame, you can use the independent levelling of the X gantry each time you turn on the printer, to make sure it stays level with the bed.
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Load the saved bed mesh.
Well, that's the process I use anyway, though rarely even bother with the bed mesh as I have a small bed with 4mm glass on it.
Ian
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@droftarts I appreciate the in depth Exploration. All the axis are level and square. I'm simply trying to keep the x gantry level on the z axis in relation to the bed to make sure it is perfectly level to the bed. What more gcode would I have to incorporate into my config/home all/home z to make this apart of the homing process?
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@Gost101 is it that it’s not working? Any error message? My guess is that:
G31 P500 X37 Y0 Z2.150
Because of your probe X offfset...
M208 X0:500 Y0:500 Z0:500
And your bed limits...
G30 P0 X30 Y250 Z-505
X30 is not reachable by the probe. Try X40.
Ian
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@droftarts It's homing as normal. It goes to the x&y endstops then to the center of the bed to probe for z. It is not probing near X30 Y250, X470 Y250. It's only probing the center of the bed. No errors are given. I've tried replacing X30 with X40 as you instructed and no fuzzy dice.
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@Gost101 what are you running? Homeall.g? You need to run bed.g, with either G32 or M98 P”bed.g”
Ian
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M98 P"bed.g" is not working when called within homeall.g
If you want to call bed.g from anywhere you can just use G32.
Your bed.g file uses both M516 and G29 S2. According to dc42 M561 does the same as G29 S2 (which has an incorrect comment) so you don't need both.
Your homez.g uses the point 15,15 for G30 but homeall.g uses 250,250 - I would use 213,250 for both files - the 213 takes the X offset of the Z probe into account so the probe ends up and 250,250.
In your config.g file the G31 P parameter is 500 but as I recall for a BLTouch it should be 25.
Frederick
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We've reached 121 posts in this thread and I think the original issue is no longer present. Do you think you could start a new thread with a restatement of the current problem? Please include all of your config files in one post. That way we can take a fresh look at everything.
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@Phaedrux sure thing. I agree.
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@fcwilt I appreciate it, I will try that now.
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We've reached 121 posts in this thread and I think the original issue is no longer present. Do you think you could start a new thread with a restatement of the current problem? Please include all of your config files in one post. That way we can take a fresh look at everything.
Well that explains why I've had this feeling of answering the same question multiple times.
Frederick
