G29 deploys before raising
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I just switched my z probe for one that is much longer and now I noticed a problem that was not noticeable before.
I'm using Firmware: RepRapFirmware for Duet 2 WiFi/Ethernet 2.05.1 (2020-02-09b1)
When running G29 S0, it will both deploy the probe for me, and also take into consideration the height needed for the probe to trigger (i.e. it moves to the first probe point while adjusting Z to my z-probe-offset + nozzle-dive-height).
The problem is that it deploys the probe BEFORE moving Z to the right level, and when the nozzle is too close to the bed at the moment I run G29 S0, it will deploy the probe, the probe will touch the bed while deploying and then be dragged over while adjusting Z and moving to the first point.
This is not a problem if you have a probe with a very small deploy travel distance, or if you are already high enough before deploying, or if you have a non-deployable probe like a inductive one. But it will be a problem if you have a probe with a very long travel (my current one has 10mm travel + 3mm dive) and it is below that height when G29 is run.
I cannot try to lift Z in my probe deploy macro because it will also be ran when running G28 and Z is not homed yet so it will not work. And I don't have mesh.g yet in the version I'm running (I'm planning to upgrade soon).
I think the order of DEPLOY and MOVE-Z should be reversed. Thoughts?
Thank you
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Actually i could move Z in deployprobe.g using G91 + G1 H2 + G90 like I do in homeall.g macro, but that would probably another lift on top of the homing lift, it would be better to just do things in the right order.
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Z should be homed before running G28S0 ?
You should also do a single G30 probe, eg. in the centre of the bed, to set the Z zero absolutely.
The heightmap values are then relative to the Z zero position.
From the calibration documents:
Before you probe the bed using G29 S0, you must establish a Z=0 datum using the Z probe.
Have a look through the whole thing:
https://duet3d.dozuki.com/Wiki/Using_mesh_bed_compensation -
@rjenkinsgb ok, maybe I was not too specific. Here is more details:
- G30 works ok, and is not related to this problem.
- Yes, the printer needs to be homed when running G29 (this means running G28 if needed). I am doing this.
The problem is still there. If the printer is homed, is near Z=0 (for whatever reason) and G29 is run, it will not lift before deploying the probe. It should (proof is that it will do it, just the order is reversed).
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In your mesh.g file just put a G1 Zn command to raise the probe to a suitable starting height.
Frederick
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@fcwilt and @dc42 Thank you for the response. I thought fw 2.x did not have mesh.g support (I checked documentation and code, even tried it, but I could be wrong).
As I commented on OP I intend to upgrade soon, but anyway, it seems this problem would occour even on 3.x if issuing a G29 S0 directly, which is still something to consider.
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@token47 said in G29 deploys before raising:
@fcwilt and @dc42 Thank you for the response. I thought fw 2.x did not have mesh.g support (I checked documentation and code, even tried it, but I could be wrong).
As I commented on OP I intend to upgrade soon, but anyway, it seems this problem would occour even on 3.x if issuing a G29 S0 directly, which is still something to consider.
Yes you will need to upgrade to v3.
When you do, remember that you have to first upgrade to v3.0 and then upgrade to the desired v3.x - I use v3.3 as I am not in the mood to deal with beta version issues.
There are, of course, changes that need to be made to your config.g file. Those changes caused me to put off upgrading for quite a while. But once I actually looked into the changes I found they were not that big of a deal I went forward with upgrading to v3.3 and am very glad I did.
Frederick
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If you still have access to DWC. Upload these 3 zip files, one at a time in the system tab. Don't extract them first. Reboot after each. Use M115 in the gcode console to verify the firmware has been applied.
https://github.com/Duet3D/RepRapFirmware/releases/download/2.05.1/Duet2Firmware-2.05.1.zip
https://github.com/Duet3D/RepRapFirmware/releases/download/3.0/Duet2and3Firmware-3.0.zip
https://github.com/Duet3D/RepRapFirmware/releases/download/3.3/Duet2and3Firmware-3.3.zip
That will get your firmware and DWC up to date.You can see the change logs here:
https://github.com/Duet3D/RepRapFirmware/wiki/Changelog-RRF-3.xFor your config, might be a good idea to run through the configurator tool and generate a fresh set for RRF3.
https://configtool.reprapfirmware.org/StartBackup your existing config files in the sys folder in case you want to switch back to RRF2. It’s easy to switch back and forth, just upload the zip file for the version you want and then upload your config files.
These documents will come in handy during the conversion.
https://duet3d.dozuki.com/Wiki/RepRapFirmware_3_overview
https://duet3d.dozuki.com/Wiki/Gcode -
By the way, what kind of probe is it?
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@phaedrux Thank you for the procedural steps. I'm reading about the upgrade and finding courage to do the upgrade, this will help. The reason for the delay is that my setup is complex, I have a ton of macros and some advanced configs, so I keep delaying it.
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@phaedrux It's a probe I designed myself. A crashprobe. It sits behind the HEVO carriage and is deployed by pushing it down from above (releasing a magnet). It can be easily deployed by hand (the printer will beep and wait for it) or go to the corner and press against another part. Still testing, but already much better than the older one which was driving me nuts. It has about 10mm of Z offset to the nozzle and another 6-7mm above the nozzle when retracted (I wanted a very long travel on both ways to avoid problems I was having before).
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Take it slow and cautiously. Reduce motor currents. Have a hand near the kill switch.
Send M98 P"config.g" to check for syntax errors.
We're always here to help.