What can cause an irregular and messy surface layer print using ABS?



  • I am using a Rostock MAX v2 and MatterHacker's PRO 1.75 mm ABS Filament (228 Hot End Temp and 80 Bed Temp). The Nozzle opening is 0.5 mm. Most of the extruded lines were clean and precise, but I noticed at the end of the print when it printed the top surface layer with long parallel strokes that the extruded material became very messy. What could have been the cause of this? If I had to guess, I would think that the nozzle couldn't handle the throughput of material and turbulence in the material flow caused irregular extrusion.




  • I was trying to upload a picture of the part, but it doesn't seem to work using Google Chrome.



  • This post is deleted!


  • Its really hard to diagnose these things without a picture. Image uploads are working for me on Chrome. Maybe your picture is too big? If not, you can always post it to Imgur.



  • Here is a link to the picture: http://imgur.com/gallery/3j9u6Lg/



  • Here is a screenshot of the speed settings in MatterControl. The green layer is the one that printed badly.



  • Are the speeds in the layer view the speed of the hot end on the xy plane or the speed of the filament being moved by the feeding stepper motor?



  • Here are the settings from the GCode file:

    ; Date 12/13/2015 00:00:00 Time 10:46
    ; avoidCrossingPerimeters = True
    ; outsidePerimetersFirst = False
    ; bottomClipAmount = 0
    ; centerObjectInXy = True
    ; continuousSpiralOuterPerimeter = False
    ; endCode = M104 S0 ; turn off temperature\nM140 S0\nG91\nG1 Z10 E-5.0 F12000\nG90\nG28 \nM84 ; disable motors
    ; zOffset = 0
    ; extruderOffsets = [[0,0],[0,0],[0,0],[0,0],[0,0],[0,0],[0,0],[0,0],[0,0],[0,0],[0,0],[0,0],[0,0],[0,0],[0,0],[0,0]]
    ; extrusionWidth = 0.5
    ; fanSpeedMaxPercent = 0
    ; fanSpeedMinPercent = 0
    ; filamentDiameter = 1.75
    ; extrusionMultiplier = 1.0
    ; firstLayerExtrusionWidth = 0.4
    ; firstLayerSpeed = 12
    ; firstLayerThickness = 0.3
    ; firstLayerToAllowFan = 0
    ; outputType = REPRAP
    ; generateInternalSupport = False
    ; infillExtendIntoPerimeter = 0.06
    ; infillPercent = 20
    ; infillType = TRIANGLES
    ; infillSpeed = 40
    ; bridgeSpeed = 60
    ; bridgeFanSpeedPercent = 100
    ; raftFanSpeedPercent = 100
    ; raftPrintSpeed = 40
    ; infillStartingAngle = 0
    ; wipeAfterRetraction = False
    ; supportInfillStartingAngle = 45
    ; insidePerimetersSpeed = 40
    ; layerThickness = 0.25
    ; minimumExtrusionBeforeRetraction = 1.5
    ; minimumPrintingSpeed = 5
    ; minimumLayerTimeSeconds = 40
    ; unretractExtraExtrusion = 0.1
    ; minimumTravelToCauseRetraction = 5
    ; numberOfBottomLayers = 3
    ; numberOfSkirtLoops = 4
    ; numberOfTopLayers = 3
    ; topInfillSpeed = 30
    ; outsidePerimeterSpeed = 35
    ; outsidePerimeterExtrusionWidth = 0.5
    ; numberOfPerimeters = 2
    ; positionToPlaceObjectCenter = [0,0]
    ; enableRaft = False
    ; raftExtraDistanceAroundPart = 5
    ; raftAirGap = .2
    ; retractionOnExtruderSwitch = 10
    ; retractionOnTravel = 6.5
    ; retractionSpeed = 110
    ; retractionZHop = 0.3
    ; skirtDistanceFromObject = 6
    ; skirtMinLength = 146.607661247253
    ; startCode = ; automatic settings before start_gcode\nG21 ; set units to millimeters\nM107 ; fan off\nT0 ; set the active extruder to 0\n; settings from start_gcode\nM104 S228\nM190 S80\nM109 S228\nG28\n; automatic settings after start_gcode\nT0 ; set the active extruder to 0\nG90 ; use absolute coordinates\nG92 E0 ; reset the expected extruder position\nM82 ; use absolute distance for extrusion
    ; toolChangeCode =
    ; supportExtruder = 0
    ; supportInterfaceExtruder = 0
    ; raftExtruder = -1
    ; supportLineSpacing = 2.5
    ; supportExtrusionPercent = 120
    ; supportMaterialSpeed = 40
    ; supportEndAngle = 0
    ; supportType = LINES
    ; supportXYDistanceFromObject = 0.7
    ; supportNumberOfLayersToSkipInZ = 1
    ; supportInterfaceLayers = 0
    ; travelSpeed = 300
    ; wipeShieldDistanceFromObject = 0
    ; wipeTowerSize = 0

  • MatterHackers

    This looks like you're just a bit under temp to me.

    I would recommend bumpin' up to 235-240C.

    Also, under Infill, I would change the Infill Overlap to .20 or .25mm. I typically use half the nozzle diameter, so in your case it would be .25mm. That should eliminate the gap between the infill and the perimeters around the hole in your part.



  • Thanks cope413, I'll try your recommendation.



  • I tried different temperatures, speeds and layer thicknesses. No luck. I noticed that the messiness starts at a spot where the z distance varies and I think that might have to do with a "flat tire" on one of my Rostock Max V2 cheapskates. I think I tightened it too much and one of the bearing sleeves got "sticky". I loosened the tension and the stickiness went away. I am now trying to see, if the prints in that area will get smoother.


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