Jump to content
Ultimaker Community of 3D Printing Experts

UMO print starts in mid air???


Recommended Posts

Posted (edited) · UMO print starts in mid air???

[UPDATE]
"prehistoric" also refers to the state of the grease along the lead screw and the z nut. it was all caked up and dried and made the z stepper loose steps. removing it, a deep clean and some new high-quality oil solved the problem.

Amazing to see a decade old UM still working great.

 

------------------- 

 

My (ancient) UM2 heated bed just gave up yesterday (separate topic), and I am trying to reactivate my (prehistoric) UMO, which i haven't used since I got the UM2 in 2015. A lot of the finessing and how to tweak gcode knowledge has been lost since then.

 

Problem: i need to get something printed today...

 

I got the GMO to home and heat up, and theoretically print again. home (0) is set to paper sheet thickness under the nozzle. I think the FW is a marlin flavor from 2014, but if there is a newer one, I can flash it (open to suggestions). I would prefer to not change the FW, because I am sure I tweaked a lot of parameters (dim, accel, pid etc) to a T for productions prints between 2011 and 2013)

 

something is wrong in the starting gcode, and the UMO prints mid air (about 15mm above the print bed). I used the original start gcode I found in Cura5, and also tried to change it, but no luck. would appreciate some pointers how to fix the start and end gcode, as well as what settings/flavors i should change in cura5 (i.e. relative or absolute E? etc). it appears the line "G1 Z0 Y50 F9000 ;move the bed and the head" doesn't move the bed back to 0. Help please

 

Quote

;start g-code

G21 ;metric values

G90 ;absolute positioning

M82 ;set extruder to absolute mode

M107 ;start with the fan off

G28 X0 Y0 ;move X/Y to min endstops

G28 Z0 ;move Z to min endstops

G1 Z15.0 F9000 ;move the platform down 15mm

G92 E0 ;zero the extruded length

G1 F200 E6 ;extrude 6 mm of feed stock

G92 E0 ;zero the extruded length again

G1 Z0 Y50 F9000 ;move the bed and the head

;Put printing message on LCD screen

M117 Printing...

 

Quote

;end g-code

M104 S0 ;extruder heater off

G91 ;relative positioning

G1 E-1 F300 ;retract the filament a bit before lifting the nozzle, to release some of the pressure

G1 Z+5 E-5 X-20 Y-20 F9000 ;move Z up a bit and retract filament even more

G28 X0 Y0 ;move X/Y to min endstops, so the head is out of the way

M84 ;steppers off

G90 ;absolute positioning

 

Quote

;print starts here

G92 E0
G92 E0
G1 F1500 E-6.5
;LAYER_COUNT:298
;LAYER:0
M107
G0 F3600 X44.098 Y38.408 Z0.3
G0 X41.786 Y41.69
;TYPE:SKIRT
G1 F1500 E0
G1 F3000 X42.09 Y40.816 E0.02611

...

 

Edited by joergen
updated
  • Link to post
    Share on other sites

    Posted · UMO print starts in mid air???
    4 hours ago, joergen said:

    [UPDATE]
    "prehistoric" also refers to the state of the grease along the lead screw and the z nut. it was all caked up and dried and made the z stepper loose steps. removing it, a deep clean and some new high-quality oil solved the problem.

    Amazing to see a decade old UM still working great.

     

    ------------------- 

     

    My (ancient) UM2 heated bed just gave up yesterday (separate topic), and I am trying to reactivate my (prehistoric) UMO, which i haven't used since I got the UM2 in 2015. A lot of the finessing and how to tweak gcode knowledge has been lost since then.

     

    Problem: i need to get something printed today...

     

    I got the GMO to home and heat up, and theoretically print again. home (0) is set to paper sheet thickness under the nozzle. I think the FW is a marlin flavor from 2014, but if there is a newer one, I can flash it (open to suggestions). I would prefer to not change the FW, because I am sure I tweaked a lot of parameters (dim, accel, pid etc) to a T for productions prints between 2011 and 2013)

     

    something is wrong in the starting gcode, and the UMO prints mid air (about 15mm above the print bed). I used the original start gcode I found in Cura5, and also tried to change it, but no luck. would appreciate some pointers how to fix the start and end gcode, as well as what settings/flavors i should change in cura5 (i.e. relative or absolute E? etc). it appears the line "G1 Z0 Y50 F9000 ;move the bed and the head" doesn't move the bed back to 0. Help please

     

     

     

     

    Always share some amazing and informative information with us, Thank you for sharing the detail.

  • Link to post
    Share on other sites

    Posted · UMO print starts in mid air???

    The code looks fine.  I think your Z speed or your Z jerk or your Z acceleration is faulty.  Or too much friction on the Z.  Try moving the Z up and down by 10mm movements to see how it does.  You can do this from the menu system.

  • Link to post
    Share on other sites

    Posted · UMO print starts in mid air???
    41 minutes ago, gr5 said:

    The code looks fine.  I think your Z speed or your Z jerk or your Z acceleration is faulty.  Or too much friction on the Z.  Try moving the Z up and down by 10mm movements to see how it does.  You can do this from the menu system.

    yes, a sticky/dirty z axis was the problem

    • Like 1
    Link to post
    Share on other sites

    • gr5 locked this topic
    Guest
    This topic is now closed to further replies.
     Share

    • Our picks

      • Ultimaker showcase | April 2022 | 4pm CEST | 10am EDT
        I'm excited because I've personally produced this showcase event, so if you are curious what else I'm up to nowadays, come check it out and say hi in the chat! It would mean a lot! 
          • Thanks
          • Like
        • 4 replies
      • New here? Get ahead with a free onboarding course
        Hi,
         
        Often getting started is the most difficult part of any process. A good start sets you up for success and saves you time and energy that could be spent elsewhere. That is why we have a onboarding course ready for
        Ultimaker S5 Pro Bundle, Ultimaker S5, Ultimaker S3 Ultimaker 2+ Connect.   
        They're ready for you on the Ultimaker Academy platform. All you need to do to gain access is to register your product to gain free access. 
        Ready? Register your product here in just 60 seconds.
          • Like
        • 11 replies
    ×
    ×
    • Create New...