multiple minor z height changes

[fluxline 0]

I have been having trouble with printing larger models with curves causing the printer to stutter during the print of the wall. I think earlier it was called hickups and was diagnosed as buffer issues. I'm sure that is the problem and I think the source can be linked back to the model complexity. But, after taking the model through Meshlab and simplifying it, I still get the same issue. When looking at the gcode, one thing I noticed is in the outer wall section there is a many minor changes in the z instruction within the same section. Example:

;TYPE:WALL-OUTER

G1 X80.011 Y80.697 Z63.7 F9000.0

G1 X81.406 Y79.35 Z63.701 F3600.0 E0.0116

G1 X82.892 Y78.103 Z63.702 E0.0232

G1 X84.461 Y76.963 Z63.703 E0.0348

G1 X86.106 Y75.935 Z63.704 E0.0463

G1 X87.819 Y75.024 Z63.706 E0.0579

G1 X89.591 Y74.235 Z63.707 E0.0695

G1 X91.413 Y73.572 Z63.708 E0.0811

G1 X93.278 Y73.037 Z63.709 E0.0927

G1 X95.175 Y72.634 Z63.71 E0.1043

G1 X97.095 Y72.364 Z63.711 E0.1159

G1 X99.03 Y72.229 Z63.712 E0.1274

G1 X100.97 Y72.229 Z63.713 E0.139

this fills the whole outer wall and that is exactly were i have the stutters. I know nothing about gcode generation so it might be normal but I don't see that any models that run correctly. Is that necessary? I can't see the system needing (or even making) those changes so why are they generated. Using openscad to build the model and Cura 12.08 to slice it so skeinforge is the culprit but hoping somebody can help me figure out if needed, and if not how to not have them generated. thx for any help.

[fluxline 0]

maybe interesting, when i slice with kisslicer I do not get the minor changes but there are just as many lines of instruction as the skeinforge slice, but with x/y movement but exactly the same entries in z and f. example:

G1 X109.12 Y119.36 Z33.92 F2267.7

G1 X108.39 Y119.69 Z33.92 F2267.7

G1 X107.72 Y119.96 Z33.92 F2267.7

G1 X106.89 Y120.27 Z33.92 F2267.7

G1 X105.44 Y120.7 Z33.92 F2267.7

G1 X104.21 Y120.98 Z33.92 F2267.7

G1 X103.25 Y121.15 Z33.92 F2267.7

G1 X101.73 Y121.33 Z33.92 F2267.7

G1 X100.5 Y121.39 Z33.92 F2267.7

G1 X99.01 Y121.37 Z33.92 F2267.7

G1 X97.61 Y121.26 Z33.92 F2267.7

G1 X97.43 Y121.26 Z33.92 F2267.7

G1 X96.29 Y121.07 Z33.92 F2267.7

G1 X95.35 Y120.89 Z33.92 F2267.7

G1 X94.72 Y120.73 Z33.92 F2267.7

G1 X94.42 Y120.68 Z33.92 F2267.7

G1 X94.15 Y120.58 Z33.92 F2267.7

[fluxline 0]

so, I think I've found what it is but have not tested it in a print yet. if .1 is used as the layer height then the 'extra' z movements are there, setting it to as low as .101 and the number of instructions are about the same as the original but with out the z-axis movement. will test the print and update.

[Daid 306]

Maybe you have the "Joris" option enabled? That setting makes the outer perimeter slowly increase in Z height.

[fluxline 0]

you're right, even though I thought I was managing this little variable. Maybe the setting is not taken from another instance of Cura? Don't know. Seems then setting joris on a large curvy model is not for weaker systems with a USB interface... makes sense.