Jump to content
UltiMaker Community of 3D Printing Experts

Extruder G Code hack for more torque


schafe
 Share

Recommended Posts

Posted · Extruder G Code hack for more torque

I have one of the original UM2 printers - 6-7 years old.  Several of these printers, like mine, had/have issues with the extruder skipping when the torque threshold is exceeded.  I seem to remember there was a g code hack to set the torque limits higher. 

 

I think it's just cut and paste to modify the code, but I've never done it, so baby instructions please.  Is there a "way too high" value?  How about a plugin that will make this change so I don't have to remember.

 

I typically print at .2mm height, .4mm dia, and 40mm/sec.  I think that's 3.2 mm3/sec.  For faberdashery PLA I set the temp at 240C.  The extruder will skip some at lower temps - usually at the worst location.

 

This leads to another question - how fast should I expect?  I know the answer is "it depends," but this rate seems low for objects where the final quality isn't critical.

 

Thanks

  • Link to post
    Share on other sites

    Posted · Extruder G Code hack for more torque

    I don't recommend it but you can mess with the current.  Generally higher current means higher torque but not if the stepper driver gets too hot in which case higher current then means lower torque.

     

    So M907 sets the current for all the axes.  This is the default, sets E axis (extruder) to 1250ma.

    M907 E1250

     

    So you can (for example) up it to 1300 ma with M907 E1300.  Or lower it to 900ma with M907 E900.  You can insert this in the gcode wherever you want the current to change.  The current will be remembered at the new level until you power off the machine.  If you want to save it more permanently add M500 which saves this setting to longer term memory on your printer.

     

    But why do you want to up the torque?  It's skipping a lot - well have you changed the teflon part in the last few years?  You should be changing the teflon part every 500 hours or so - check your printing hours in the menu system on the printer.  As that teflon gets old the extruder has to work harder and harder until it starts skipping.

     

    Or maybe you are just printing too fast for your extruder.

     

    Or you could upgrade to the "plus" to make yours a UM2+ printer.

     

    Or you could do the meduza upgrade (I sell a $19 kit but only if you are in USA).  The meduza upgrade and also the "plus" upgrade increase the feeder torque by 2X and it's a great upgrade.  The "plus" upgrade costs around $400 USD but you get some other nice bonuses.

  • Link to post
    Share on other sites

    Posted · Extruder G Code hack for more torque

    Why does everything have to be so hard . . .

     

    In the pic you see a recently failed print.  The lower levels were nearly perfect.  There is a section with a skip below the t on the build plate.  When the print got to the upper layers, the ones with more retractions for nozzle jumps, there are way, way more extruder skips to the point where I terminated the print.  When I discovered the skips I slowed the speed to 50%, so it was at 1.6 mm3/sec.  I did have the "retraction prime extra amount" set at 3mm3 to compensate for the blob that oozes from the nozzle during a retraction move.  If I can make the temp about 220C, that blob more or less goes away.  I will retry with the value set to 0.

     

    I have not replaced the teflon part in a long time and have used a 1/8" dia drill bit to reshape the hole.

     

    I've been printing for 6 years now, m/l.  At this point, it still feels like every print is an experiment.

     

    Here's hoping you have plenty of TP.  If not, I can box up some corn cobs from Iowa to send your way.

     

    IMG_4979.thumb.JPG.54d51a45f1a48682a05df52b34e9b71e.JPG

  • Link to post
    Share on other sites

    Posted · Extruder G Code hack for more torque

    Definitely replace the ptfe part.  I'm sure you've done more than 500 hours in the last 6 years or so.  People who use their printers every day replace them typically every 3 months.  Drilling it out while under pressure (while in the head) and very carefully, is a good way to extend the life long enough while waiting for your shipment to arrive.

  • Link to post
    Share on other sites

    Posted · Extruder G Code hack for more torque

    After changing the "retraction prime extra amount" to 0, the next print turned out perfect.  I did have to set the flow to around 2.5mm3/sec and the temp to 240C, but it worked.

  • Link to post
    Share on other sites

    Posted · Extruder G Code hack for more torque

    You have massive underextrusion in the photo.

     

    Yeah it's the flow, not the extra prime.  Well you shouldn't be doing extra prime - I suppose that could cause the extruder to skip a bit.  I just tested an original UM2 with original feeder (but new bowden and new teflon) and it was able to do 10 mm^3/sec with no underextrusion.  It could do 16 mm^3/sec with slight underextrusion (about 10% - very thin cracks between infill lines).

     

    Change the ptfe.  It will change your life, lol.  Oh wait - I think you just ordered one from my store.  I think you will be pleased.

     

  • Link to post
    Share on other sites

    Posted · Extruder G Code hack for more torque

    Thanks for the help. 

     

    Right now I am printing the 3 parts for the extruder upgrade.  I changed the setting "optimize walls," (or something like that,) to on.  It eliminated a lingering question I have always had, "why does Cura jump to a circle and print one wall section, then retract and jump to another circle and print one wall section, then jump to the outside wall and print one section, etc, etc."  After turning that on, it will print all sections of a wall, then go to another location and print those walls.  This saves a lot of retraction/jump moves and seems to make it all run better.

     

    I also turned combing to "all" vs "none."  With these changes I get awesome results and can print way faster.

     

    I still don't understand combing.

  • Link to post
    Share on other sites

    Posted · Extruder G Code hack for more torque

    On a side note, I work in the maintenance dept for a major food manufacturer.  They trust me with their multi-million dollar cereal packaging equipment, some of which is extremely technical.  I am frustrated by the help features offered by the manufacturer.  The description of the functions were written by the engineers who designed and programmed the machines - they totally understand how it works.  I wish they hired a farmer to write the descriptions - dumb it down a little.

     

    I wish the folks who write the Cura help descriptions did the same thing.  Maybe add a pic to describe what a feature does.

  • Link to post
    Share on other sites

    Create an account or sign in to comment

    You need to be a member in order to leave a comment

    Create an account

    Sign up for a new account in our community. It's easy!

    Register a new account

    Sign in

    Already have an account? Sign in here.

    Sign In Now
     Share

    • Our picks

      • Here it is. The new UltiMaker S7
        The UltiMaker S7 is built on the success of the UltiMaker S5 and its design decisions were heavily based on feedback from customers.
         
         
        So what’s new?
        The obvious change is the S7’s height. It now includes an integrated Air Manager. This filters the exhaust air of every print and also improves build temperature stability. To further enclose the build chamber the S7 only has one magnetically latched door.
         
        The build stack has also been completely redesigned. A PEI-coated flexible steel build plate makes a big difference to productivity. Not only do you not need tools to pop a printed part off. But we also don’t recommend using or adhesion structures for UltiMaker materials (except PC, because...it’s PC). Along with that, 4 pins and 25 magnets make it easy to replace the flex plate perfectly – even with one hand.
         
        The re-engineered print head has an inductive sensor which reduces noise when probing the build plate. This effectively makes it much harder to not achieve a perfect first layer, improving overall print success. We also reversed the front fan direction (fewer plastic hairs, less maintenance), made the print core door magnets stronger, and add a sensor that helps avoid flooding.
         

         
        The UltiMaker S7 also includes quality of life improvements:
        Reliable bed tilt compensation (no more thumbscrews) 2.4 and 5 GHz Wi-Fi A 1080p camera (mounted higher for a better view) Compatibility with 280+ Marketplace materials Compatibility with S5 project files (no reslicing needed) And a whole lot more  
        Curious to see the S7 in action?
        We’re hosting a free tech demo on February 7.
        It will be live and you can ask any questions to our CTO, Miguel Calvo.
        Register here for the Webinar
          • Like
        • 10 replies
      • UltiMaker Cura 5.3.0-Alpha 🎄 Tree Support Spotlight 🎄
        Are you a fan of tree support, but dislike the removal process and the amount of filament it uses? Then we would like to invite you to try this special release of UltiMaker Cura. Brought to you by our special community contributor @thomasrahm
         
        We generated a special version of Cura 5.2 called 5.3.0 Alpha + Xmas. The only changes we introduced compared to UltiMaker Cura 5.2.1 are those which are needed for the new supports. So keep in mind, this is not a sneak peek for Cura 5.3 (there are some really cool new features coming up) but a spotlight release highlighting this new version of tree supports.  
          • Like
        • 17 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
        • 14 replies
    ×
    ×
    • Create New...