Issues with extruding after retractions



  • Hello everyone,

    first of all I'm in love with my duet2wifi damn what a joy to just be able to toss gcodes to your browser and having it print.

    so I have finished my hypercube evo for 2 weeks now and all in all I love the design and all the bells and whistles I added to it. though this is the first time using a bowden and I just can't figure out why it's underextruding after a retraction, I searched everywhere online and couldn't seem to solve it. please be my hero and safe me.

    https://imgur.com/a/N2jzdjT

    I think all the info is in the imgur pictures, if you need anything else I can deliver.

    edit : i'm running firmware 2.01(RTOS)



  • It's hard to tell looking at the images what your Cura settings are but if you are using combing then it's a good idea to set the max comb distance before retract to something like 10 or 20. That will reduce the dribble that can occur during combing. It would be useful if you could attach some gcode that exhibits the problems.



  • 0_1549732657477_bridging test gcode with failing toplayers.gcode

    here is the gcode for the bridging test where the top layer failed. also looking at the path it takes and the model on my desk it's only showing serious issues after long travel moves. so on one side the middle part is fine but the second layer is not because it's "priming" and on the other side the inner wall is missing because it's using that as "prime" or something.



  • I looked at your gcode and it is as I suspected, doing long travels with no retract. Set the max comb dist without retract to, say, 10 and things will improve.



  • 0_1549737876420_IMG_20190209_194227.jpg

    left is with max comb distance of 10 (top surface on the bridges look a lot better)
    right is with combing turned off.

    sadly enough this doesn't seem to fix it :<



  • I can't see anything else obvious in the gcode that would explain the gaps between the skins and the walls so it must be a combination of factors that are conspiring to cause the under extrusion.

    You have calibrated your extruder and checked that your filament is the correct diameter and not undersized? The temperature is right for that filament?

    There's a Cura setting called Skin Overlap Percentage that you can use to grow the skins so that they overlap the walls. Perhaps that needs increasing? I am currently using 5% and don't get the gaps like you are seeing.



  • the weird part is that it only happens when it travels a long while and than has to extrude, if you look at my calibration cubes the top layer is mostly perfect. I just can't seem to figure out what the issue is. temp is fine and filament diameter is 1.78

    i'm still at a loss



  • And you have tried using more retraction? The gcode file above shows it to be 3.1mm which maybe isn't enough for your Bowden tube?



  • like it's not preducing any blobs or stings on this setting it's only acting up after a travel



  • @gear said in Issues with extruding after retractions:

    like it's not preducing any blobs or stings on this setting it's only acting up after a travel

    Sure, but have you tried using more retraction?



  • Try extra prime?


 

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