The self proclaimed "pulley nirvana" from a previous post didn't last long. It seems that changing extruder, filament, or perhaps the weather, had caused a regression in the pulley prints I need for my upcoming Huxley/Mini-Mendel, even though the same gcode was used - with the cool setting and a slower feed/flow rate. The print goes fine until a third through the spurs of the gear, and then the flow splutters and starts, causing a very deformed (and unusable) gear.

 

At first I thought the cause might lie in too high a temperature, and so I reduced the hot end temperature to 180°C (from 195°C), and also placed a desktop fan adjacent to the bed, on the lowest setting. The results were still poor.

It seems that the Dimension module in Skeinforge was retracting the filament too much (because the speed was so much lower, it had more time to retract) and consequently the beginning of each layer on the spurs was receiving less and less material. Hence the deformity. Changing this value from 1.3 to 0.2 brought about much better results.

Not perfect, but usable, and a step in the right direction.

Below are the Skeinforge settings used in case they are useful.

Skeinforge Settings

Important
Layer Thickness (mm): 0.4
Perimeter Width over Thickness (ratio): 1.4
Infill Solidity (ratio): 0.3
Feed Rate (mm/s): 25.0
Flow Rate Setting (float): 25.0
dimension
Absolute Extrusion Distance True
Relative Extrusion Distance False
Extruder Retraction Speed (mm/s): 20.0
Filament Diameter (mm): 2.85
Filament Packing Density (ratio): 1.0
Retraction Distance (millimeters): 0.2
Restart Extra Distance (millimeters): 0.0
carve
Add Layer Template to SVG True
Extra Decimal Places (float): 2.0
Import Coarseness (ratio): 1.0
Infill in Direction of Bridge True
Layer Thickness (mm): 0.4
Layers From (index): 0
Layers To (index): 912345678
Correct Mesh True
Unproven Mesh False
Perimeter Width over Thickness (ratio): 1.4
SVG Viewer: webbrowser
chop
Add Extra Top Layer if Necessary True
Add Layer Template to SVG True
Extra Decimal Places (float): 2.0
Import Coarseness (ratio): 1.0
Layer Thickness (mm): 10.0
Layers From (index): 0
Layers To (index): 999999999
Correct Mesh True
Unproven Mesh False
Perimeter Width (mm): 2.0
SVG Viewer: webbrowser
comb
Activate Comb True
cool
Activate Cool True
Bridge Cool (Celcius): 1.0
Orbit False
Slow Down True
Maximum Cool (Celcius): 2.0
Minimum Layer Time (seconds): 10.0
Minimum Orbital Radius (millimeters): 10.0
Name of Cool End File: cool_end.gcode
Name of Cool Start File: cool_start.gcode
Turn Fan On at Beginning True
Turn Fan Off at Ending True
dimension
Activate Dimension True
Absolute Extrusion Distance True
Relative Extrusion Distance False
Extruder Retraction Speed (mm/s): 20.0
Filament Diameter (mm): 2.85
Filament Packing Density (ratio): 1.0
Retraction Distance (millimeters): 0.2
Restart Extra Distance (millimeters): 0.0
fill
Activate Fill: True
Diaphragm Period (layers): 100
Diaphragm Thickness (layers): 0
Extra Shells on Alternating Solid Layer (layers): 0
Extra Shells on Base (layers): 0
Extra Shells on Sparse Layer (layers): 0
Grid Circle Separation over Perimeter Width (ratio): 0.2
Grid Extra Overlap (ratio): 0.1
Grid Junction Separation Band Height (layers): 10
Grid Junction Separation over Octogon Radius At End (ratio): 0.0
Grid Junction Separation over Octogon Radius At Middle (ratio): 0.0
Infill Begin Rotation (degrees): 45.0
Infill Begin Rotation Repeat (layers): 1
Infill Odd Layer Extra Rotation (degrees): 90.0
Grid Circular False
Grid Hexagonal False
Grid Rectangular False
Line True
Infill Perimeter Overlap (ratio): 0.15
Infill Solidity (ratio): 0.3
Infill Width over Thickness (ratio): 1.3
Solid Surface Thickness (layers): 1
Lower Left True
Nearest False
Infill > Loops > Perimeter False
Infill > Perimeter > Loops False
Loops > Infill > Perimeter False
Loops > Perimeter > Infill True
Perimeter > Infill > Loops False
Perimeter > Loops > Infill False
home
Activate Home True
Name of Homing File: homing.gcode
inset
Add Custom Code for Temperature Reading True
Bridge Width Multiplier (ratio): 1.0
Ascending Area True
Descending Area False
Overlap Removal Width over Perimeter Width (ratio): 0.6
Turn Extruder Heater Off at Shut Down True
limit
Activate Limit True
Maximum Initial Feed Rate (mm/s): 80.0
Maximum Z Feed Rate (mm/s): 1.0
multiply
Activate Multiply: True
Center X (mm): 50.0
Center Y (mm): 50.0
Number of Columns (integer): 1
Number of Rows (integer): 1
Separation over Perimeter Width (ratio): 15.0
preface
Name of End File: end.gcode
Name of Start File: startMendel05l04PLA.gcode
Set Positioning to Absolute True
Set Units to Millimeters True
Start at Home False
Turn Extruder Off at Shut Down False
Turn Extruder Off at Start Up False
raft
Activate Raft True
Add Raft, Elevate Nozzle, Orbit: True
Base Feed Rate Multiplier (ratio): 1.0
Base Flow Rate Multiplier (ratio): 1.0
Base Infill Density (ratio): 0.5
Base Layer Thickness over Layer Thickness: 2.0
Base Layers (integer): 0
Base Nozzle Lift over Base Layer Thickness (ratio): 0.2
Initial Circling: False
Infill Overhang over Extrusion Width (ratio): 0.05
Interface Feed Rate Multiplier (ratio): 1.0
Interface Flow Rate Multiplier (ratio): 1.0
Interface Infill Density (ratio): 0.5
Interface Layer Thickness over Layer Thickness: 1.0
Interface Layers (integer): 0
Interface Nozzle Lift over Interface Layer Thickness (ratio): 0.45
Name of Support End File: support_end.gcode
Name of Support Start File: support_start.gcode
Object First Layer Feed Rate Infill Multiplier (ratio): 0.4
Object First Layer Feed Rate Perimeter Multiplier (ratio): 0.4
Object First Layer Flow Rate Infill Multiplier (ratio): 0.4
Object First Layer Flow Rate Perimeter Multiplier (ratio): 0.4
Operating Nozzle Lift over Layer Thickness (ratio): 0.5
Raft Additional Margin over Length (%): 1.0
Raft Margin (mm): 3.0
Support Cross Hatch False
Support Flow Rate over Operating Flow Rate (ratio): 1.0
Support Gap over Perimeter Extrusion Width (ratio): 1.0
None True
Empty Layers Only False
Everywhere False
Exterior Only False
Support Minimum Angle (degrees): 60.0
speed
Activate Speed: True
Add Flow Rate: True
Bridge Feed Rate Multiplier (ratio): 1.0
Bridge Flow Rate Multiplier (ratio): 1.0
Duty Cyle at Beginning (portion): 1.0
Duty Cyle at Ending (portion): 0.0
Feed Rate (mm/s): 25.0
Flow Rate Setting (float): 25.0
Orbital Feed Rate over Operating Feed Rate (ratio): 0.5
Perimeter Feed Rate over Operating Feed Rate (ratio): 0.7
Perimeter Flow Rate over Operating Flow Rate (ratio): 0.7
Travel Feed Rate (mm/s): 30.0
stretch
Activate Stretch True
Cross Limit Distance Over Perimeter Width (ratio): 5.0
Loop Stretch Over Perimeter Width (ratio): 0.11
Path Stretch Over Perimeter Width (ratio): 0.0
Perimeter Inside Stretch Over Perimeter Width (ratio): 0.64
Perimeter Outside Stretch Over Perimeter Width (ratio): 0.1
Stretch From Distance Over Perimeter Width (ratio): 2.0