Delta Rostock mini G2s Extruder drives Axial motors

[brent_jackson]

On my system I have completed initial build and calibration but have yet to be able to print anything.

What I observe is that, using the Repetier-Host interface, manual commands to advance extruders will occasionally cause X/Y/Z axial stepper motors to activate, driving upwards. If the system is in home position, the end stop signals are ignored and I have to do an emergency stop.

Repeatability is not 100%, but here are steps I have used:

1. Connect
2. Select Manual Control Tab...
3. Home system
4. Click Heat Extruder
5. Select Extruder 2
6. Click Heat Extruder
7. Wait for extruders to heat to 200C
8. Select Extruder 1
9. Click down arrow by Extrude
10. Select Extruder 2
11. Click down arrow by Extrude
12. observe axial motors driving up with shaking click
13. Click Emergency Stop

Using G2S firmware downloaded 15aug2015. Internal file dates are 16jul2015.

[Mark]

If your wires were correct connected, might it be the firmware's problem?

[JHill42]

Hello Brent,

I had a similar problem - it seems to behave badly shaking its way to the top and ignoring the endstops. I purchased another GT2560 and replacement A4988 (stepper motor boards), but the problem remained. It didn't do it all the time, but it sometimes took 10-20 power cycles to get it working OK - after it was OK, it could run for many hours without troubles.

I finally narrowed it down to a couple of G-code command that seem to cause issues. The commands are G1 Z15 Fxxxx (where xxxx is a travel rate) and G92 E0. When using the GeeeTech version of Repetier (an older version from the instructions), I would run the slicer and edit the G-codes to remove the problem commands. I also found that adding a G28 (home) right before printing helped with positioning. Using the newer versions of Repetier - I've switched to the Curra slicer and just comment out the G1 Z15 Fxxxx line in the G-code setup. I also found that I needed to add a conditional tool select (T0 or T1), to select the extruder - this also goes in the startup G-codes section.

I think there must be some bug in the firmware that causes this, but I haven't looked into it.

I hope this helps,

Jeff

[brent_jackson]

Thank you both Mark and Jeff for your responses.

I imagine that if the motors were incorrectly connected, then I would not be able to home the system and extrusion would not sometimes work.

I have since updated to the August 24 version of the firmware with no perceivable difference in behavior.

I might have to try power cycling to see if that fixes the issue.

I am using the Geetech Repetier Host app V0.90D... from what Jeff writes, perhaps that is not the best choice. I'm open to suggestions.

With respect to the G-code commands that seem to cause issues, it seems pretty daunting if I have to manually edit the code for each sliced object. At this point I'm only trying to manually extrude and have not yet attempted to print a single piece. When I click the button to manually extrude 10mm on Extruder 1, I see the following commands sent to the printer:
G91 *53
G1 E10 F1000 *62
G90 *54

None of these seem to be the G-codes you have identified, but perhaps it is a similar problem.

As I write this, extruder 1 now seems starting to behave as desired, but I expect the wrong behavior to return after reboot.

Just FYI, I also have issues with auto leveling similar to the Autolevelling destruction G2S thread.

[Mark]

I know this one behavior: print with extruder 1 is OK, and if you manually control extruder 2 then the other axis will move up and extruder 2 have no response.
This is a bug and we'll fix it asap!

[JHill42]

Hello Brent,

I'm pretty sure my problem was not wiring, but a firmware issue. I jammed up the first extruder pretty good (was able to unclog later) and started using the second one. With multiple versions of Repetier I ran into the problem - so I don't think it has anything to do with the version used. It just seems to be certain codes that cause problems. I used the G-code editor to comment out lines until it worked OK. I now use the newer version of Repetier and the Curra - this has a default job G-code section which I edited to remove the G1 Z15 Fxxxx line and added the conditional tool select (T0 or T1) - you won't need to do this each time. There may be other codes that cause issues, but I haven't run into them. For what it is worth, my manual extrudes do work, but I think I set to a lower feed rate (something like 50 or 25).

Mark - when you get a fix, please let me know - I'd love to give it a try...

Thanks,

Jeff

[flamtap]

I know this one behavior: print with extruder 1 is OK, and if you manually control extruder 2 then the other axis will move up and extruder 2 have no response.
This is a bug and we'll fix it asap!

I have been printing with one extruder successfully for a few weeks. Tonight I started working on getting the 2nd extruder running, and I am seeing this exact problem.

When I go to manually extrude using repetier, all 3 axes start moving upward. Please provide a fix ASAP!

flamtap

[Mark]

We are testing the latest firmware now, it won't take long to fix the problem, plz wait with patience, tks!

[rickr]

HI Flamtap,

Are you saying that after you "#defined 2 extruders" in your firmware, then you started having the problems we have all experienced?

Cheers, Rick

[flamtap]

Rick,

Yes, but defining 2 extruders does not seem to trigger the problem. It only seems to happen when the 2nd extruder is told to actually extrude something.

I can still print "normally" using just the first extruder, even with 2 defined.

flamtap