Calibrating slicer for nozzle size, need references

Discussion in 'E3D-v6 and Lite6' started by dbeck002, Apr 11, 2016.

  1. dbeck002

    dbeck002 Member

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    Hello,


    I am running E3D bowden with a bondtech QR. I am using the 0.6mm nominal nozzles supplied to me by E3D, I bought separate. If I put 0.6mm nozzle diameter in S3D, I get massive amounts of overextrusion. I lowered the value to 0.59, then 0.58 etc... All the way down to 0.54 and it does help but I need to know what values you guys are using for the nozzles? I took a 0.6mm drill bit and it fit perfectly snug in the nozzle, I measured the bit with my digital calipers and it comes out at 0.55mm. This number is critical especially for bowden extruders. Can someone please shed some light? I would hate to have to use extrustion multipliers as this tricks the machine into extruding the right amount but with the wrong nozzle diameter and this may effect my W/T capability if I need to go wide layers.

    Thanks
     
  2. elmoret

    elmoret Administrator

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    Nozzle diameter should not be adjusted to compensate for over extrusion. It is best to set steps/mm by measurement:

    http://reprap.org/wiki/Triffid_Hunter's_Calibration_Guide#E_steps

    All Simplify3D needs nozzle width for is if you're setting extrusion width to auto, in which case it sets extrusion width to 120% of nozzle width. You can use any extrusion width you like, though ideal is between 110 and 130% of nozzle width in most cases.

    Again - It is best to correct for over extrusion with steps/mm or extrusion multiplier, not nozzle width. Simplify3D cover this as well in their print troubleshooting guide.

    https://www.simplify3d.com/support/print-quality-troubleshooting/#extruding-too-much-plastic
     
    #2 elmoret, Apr 11, 2016
    Last edited: Apr 12, 2016
  3. dbeck002

    dbeck002 Member

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    It is technically not over extruding in the sense of steps/mm because the stepper is calibrated properly. It is over extruding because the math that S3D is using to compute massflow is off because I dont have the correct nozzle diameter. It needs to be right, or close to right, or I will pump out more than necessary because thats what S3D uses to compute the flow. Extrusion width I use is around 0.65mm, the nozzle is 0.6mm nominal, the layers come out way over extruded. esteps are calibrated, flow rates are at 100% with no augmentation factors.
     
  4. Miasmictruth

    Miasmictruth Well-Known Member

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    Is it all layers or just the lower layers? Did you measure the filament diameter?
     
  5. elmoret

    elmoret Administrator

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    I really don't think that's true. S3D doesn't care what the nozzle diameter is, unless you have extrusion width set to auto and in that case it just uses the nozzle diameter set to extrusion width. Some evidence:

    https://www.diffchecker.com/tooysoet

    That's the same STL sliced with two different nozzle diameters and a manual extrusion width. Check the g-code, it is identical.
     
  6. dbeck002

    dbeck002 Member

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    So what could cause me to have to us 0.55mm instead of 0.6mm? Same width, same everything. Over extrudes with 0.6mm, correct extrusion at 0.55mm. Could it be related to pressure built up with the smaller nozzle thus restricting flow? But that shouldnt matter, the extruder speed controls the flow regardless of the backpressure of the nozzle, mm/s of filament is mm/s of filament. I am not sure then why changing the nozzle diameter helps with print quality. Perhaps it has something to do with the width I am using. I tried 0.7mm and wide, nothing too big for a 0.6mm nozzle. Prints seemed way to filled in. What should I do then if I feel like I am over extruding and the nozzle diameter doesnt effect this and the esteps are calibrated?
     

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