Z height not accurate

[dunginhawk]

Good morning.. So im trying to get ABS working on my prusa... Its printing PLA ok and now when i try to run a print at .3 layer height, after the printer homes axis, it rises up .3 as its supposed , i also have a command to start printing at -.3. Ive tried -.6 and -1 etc and it doesnt seem to move at all, so its not adjust that...
please advise if anyone has seen this.
thanks

EDIT: the idea is that i want to bring the nozzle back down closer to the glass before i start printing thanks
Looking through the Gcode, i dont see a command in there after raising the z to .3. i see nothing putting it back down .3 or whatever i set that value to

[KeyboardWarrior]

Could you post a G-Code file or factory file for more information.

Also, if you set your first layer height to 10%, that would effectively drop your print .27 mm for the first layer, which may help.

[dunginhawk]

here is the first part that matters.

; G-Code generated by Simplify3D(R) Version 2.2.2
; Mar 27, 2015 at 11:01:10 AM
; Settings Summary
; processName,MakerFarm 12" prusa Hex
; applyToModels,z_motor_mount-v2.1-nonswitch-right
; profileLabel,Prusa Mendel
; printMaterial,ABS
; printQuality,Medium
; extruderName,Primary Extruder
; extruderToolheadNumber,0
; extruderDiameter,0.4
; extruderAutoWidth,0
; extruderWidth,0.4
; extrusionMultiplier,1
; extruderUseRetract,1
; extruderRetractionDistance,1
; extruderExtraRestartDistance,0
; extruderRetractionZLift,0
; extruderRetractionSpeed,1800
; extruderUseCoasting,0
; extruderCoastingDistance,0.2
; extruderUseWipe,0
; extruderWipeDistance,5
; primaryExtruder,0
; layerHeight,0.3
; topSolidLayers,3
; bottomSolidLayers,3
; perimeterOutlines,1
; printPerimetersInsideOut,1
; startPointOption,2
; startPointOriginX,0
; startPointOriginY,0
; startPointOriginZ,300
; sequentialIslands,0
; spiralVaseMode,0
; firstLayerHeightPercentage,100
; firstLayerWidthPercentage,100
; firstLayerUnderspeed,0.5
; useRaft,0
; raftExtruder,0
; raftLayers,3
; raftOffset,3
; raftSeparationDistance,0.14
; raftInfill,85
; disableRaftBaseLayers,0
; useSkirt,1
; skirtExtruder,0
; skirtLayers,1
; skirtOutlines,1
; skirtOffset,10
; infillExtruder,0
; externalInfillPattern,Rectilinear
; infillPercentage,50
; outlineOverlapPercentage,15
; infillExtrusionWidthPercentage,100
; minInfillLength,5
; infillLayerInterval,1
; randomInfillStartPoint,0
; infillAngles,45,-45
; generateSupport,0
; supportExtruder,0
; supportInfill,20
; supportExtraInflation,0
; denseSupportLayers,0
; denseSupportInfill,70
; supportLayerInterval,1
; supportHorizontalPartOffset,0.3
; supportUpperSeparationLayers,1
; supportLowerSeparationLayers,1
; supportGridSpacing,4
; maxOverhangAngle,45
; supportAngles,0
; temperatureName,Primary Extruder,Heated Bed
; temperatureNumber,0,1
; temperatureSetpointCount,1,1
; temperatureSetpointLayers,1,1
; temperatureSetpointTemperatures,230,90
; temperatureStabilizeAtStartup,1,1
; temperatureHeatedBed,0,1
; temperatureRelayBetweenLayers,0,0
; temperatureRelayBetweenLoops,0,0
; fanLayers,1
; fanSpeeds,0
; blipFanToFullPower,1
; adjustSpeedForCooling,1
; minSpeedLayerTime,15
; minCoolingSpeedSlowdown,20
; increaseFanForCooling,0
; minFanLayerTime,45
; maxCoolingFanSpeed,100
; increaseFanForBridging,0
; bridgingFanSpeed,100
; use5D,1
; relativeEdistances,0
; allowEaxisZeroing,1
; independentExtruderAxes,0
; includeM10123,0
; stickySupport,1
; detectArcs,0
; arcReplaceG2G3,0
; arcRadialCompensation,1
; gcodeXoffset,0
; gcodeYoffset,0
; gcodeZoffset,0
; overrideMachineDefinition,1
; machineTypeOverride,0
; strokeXoverride,300
; strokeYoverride,300
; strokeZoverride,300
; originOffsetXoverride,0
; originOffsetYoverride,0
; originOffsetZoverride,0
; homeXdirOverride,-1
; homeYdirOverride,-1
; homeZdirOverride,-1
; flipXoverride,1
; flipYoverride,-1
; flipZoverride,1
; startingGcode,G28 ; home all axes,
; layerChangeGcode,
; toolChangeGcode,
; endingGcode,M104 S0 ; turn off extruder,M140 S0 ; turn off bed,G28 X0 ; home X axis,M84 ; disable motors
; createX3G,0
; celebration,0
; celebrationSong,Random Song
; createMB5G,0
; postProcessing,
; defaultSpeed,4200
; outlineUnderspeed,0.6
; solidInfillUnderspeed,0.7
; supportUnderspeed,0.5
; rapidXYspeed,4800
; rapidZspeed,1002
; minBridgingArea,50
; bridgingExtrusionMultiplier,1
; bridgingSpeedMultiplier,1
; filamentDiameter,1.75
; filamentPricePerKg,46
; useMinPrintHeight,1
; minPrintHeight,-0.3
; useMaxPrintHeight,0
; maxPrintHeight,0
; useDiaphragm,0
; diaphragmLayerInterval,20
; robustSlicing,1
; mergeAllIntoSolid,0
; onlyRetractWhenCrossingOutline,1
; retractBetweenLayers,1
; useRetractionMinTravel,0
; retractionMinTravel,3
; useRetractionOozeRate,0
; retractionOozeRate,6000
; onlyWipeOutlines,1
; toolChangeRetractionDistance,12
; toolChangeExtraRestartDistance,-0.5
; toolChangeRetractionSpeed,600
; allowThinWallGapFill,1
; thinWallAllowedOverlapPercentage,10
; horizontalSizeCompensation,0
G90
M82
M127
M140 S90 T0
M134 T0
M104 S230 T0
M133 T0
G28 ; home all axes

G92 E0
G1 E-1 F1800
G1 Z0.3 F1002
; layer 1, Z = 0.3
M135 T0
; tool H0.3 W0.4
G1 X80.745 Y109.83 F4800
G1 E0 F540
G92 E0
G1 X80.818 Y109.8 E0.004 F2100
G1 X219.182 Y109.8 E6.907
G1 X219.255 Y109.83 E6.9109
G1 X225.17 Y115.745 E7.3282
G1 X225.2 Y115.818 E7.3322
G1 X225.2 Y184.182 E10.7429
G1 X225.17 Y184.255 E10.7468
G1 X219.255 Y190.17 E11.1641
G1 X219.182 Y190.2 E11.1681
G1 X80.818 Y190.2 E18.0711
G1 X80.745 Y190.17 E18.0751
G1 X74.83 Y184.255 E18.4923
G1 X74.8 Y184.182 E18.4963
G1 X74.8 Y115.818 E21.907
G1 X74.83 Y115.745 E21.9109
G1 X80.745 Y109.83 E22.3282
G92 E0
G1 E-1 F1800
G1 X85.2 Y120.2 F4800
G1 E0 F1800
G92 E0
G1 X214.8 Y120.2 E6.4658 F1260
G1 X214.8 Y179.8 E9.4392
G1 X85.2 Y179.8 E15.905
G1 X85.2 Y120.2 E18.8785
G1 X98.733 Y138.597 F4800

[KeyboardWarrior]

Your G-Code offset appears to be set to Zero in the Z-axis, if you go to the G-Code tab and change it to -.3 mm and slice again, your Z-height for the first layer should be 0.

[dunginhawk]

i see a lot of z offset stuff in here, which line in particular do i need to edit?

Not to be picky, but shouldnt that value in the gui be doing that for me? that is the idea right? just confusing as to why it wouldnt be.
thank you

[KeyboardWarrior]

i see a lot of z offset stuff in here, which line in particular do i need to edit?

Not to be picky, but shouldnt that value in the gui be doing that for me? that is the idea right? just confusing as to why it wouldnt be.
thank you

It would go under this section.

[dunginhawk]

so yes, i just found that info. and yes, that works with my configuration now.

However, in the settings advanced, layer modifications, isnt that where you can change it to start printing at a certain height? or am i confused?
thank you very much for your help

[JoeJ]

You only use those advanced start/stop printing at height options if you want to use different settings for different regions of a print (https://www.simplify3d.com/support/tuto ... f-a-model/)