The basic parameters that control objects are:
- Layer Height (Layer thickness)
This controls the thickness of each layer, how 'fine' the object is printed or resolution. - Extrusion Width
This is the width of the extrusion, and controls placement of lines of plastic. strength of the object
Extrusion Rate is actually separated into 3 separate settings: - Edge Width over Height
- Infill Width over Thickness
- Extrusion Diameter Over Thickness
- Feed Rate (Head Speed)
This is the speed that the build platform moves past the nozzle. - Flow Rate
This is how fast the extruder motor is turning and how fast a given length of plastic is going into the extruder.
- Layer height(H) 80% of < nozzle diameter >= Extrusion width(W)
- 0.35 * 0.8 = 0.28mm(H) < 0.35mm nozzle >= 0.4mm(W)
- 0.5 * 0.8 = 0.4mm(H) < 0.5mm nozzle >= 0.5mm(W)
- Extrusion Rate is actually separated into 3 separate settings:
- Crave -> Carve -> Edge Width over Height (PW/H) = W/H
- 0.4 / 0.28 = 1.42
- 0.5 / 0.4 = 1.25
- Crave -> Fill -> Infill Width over Thickness (IW/T) = W/H
- 0.4 / 0.28 = 1.42
- 0.5 / 0.4 = 1.25
- Analyse-> Statistic -> Extrusion Diameter over Thickness (ratio) = W/H
- 0.4 / 0.28 = 1.42
- 0.5 / 0.4 = 1.25
- Crave -> Speed -> Flow rate = (Feed rate = Travel Feed Rate)
- Crave -> Dimension
- Filament Diameter = [Take average measurement form multiple points with caliper]
- (2.90 + 2.95 + 3.00 + 2.92 + 2.94) / 5 points = 2.94
- Filament Packing Density = 1 PLA, 0.8 ABS
- The higher the resolution the longer it will take to process and print the object
- If you increase layer height, you want to decrease width over thickness, and if you decrease layer height you want to increase width over thickness.
>> Work in progress..
3D Printer: Durbie Prusa Mendel by Romscraj.com
Version: Skeinforge49
Plastic Type: PLA
Nozzle Diameter(mm): 0.5 (default 0.5)
Profile Type: Extrusion
Profile Selection: Durbie Normal PLA 0.5N 0.4H 1.25WH
SF49 - Craft Sequence:
Carve ->
Note:
Carve
- Layer Height/Thickness (mm): 0.4 (default 0.4)
- Edge Width over Height (ratio): 1.5 (default 1.8)
Inset
The default value is 0.1, reduce this and the gap gets wider, increase this and the overlap is larger. Test with value finished up at 0.3 to give a nice clean join up to the perimeter.
- Infill Width over Thickness (ratio): 1.5 (default 1.5)
- Infill Solidity (ratio): 0.25 (default 0.2)
- Infill Width over Thickness (ratio): 1.5 (default 1.5)
Note: Increase value to reduce extruded plastic or decrease value to expand extruded plastic
Multiply
- Activate Multiply
- Center X (mm): 100.0
- Center Y (mm): 100.0
- Activate Speed
- Add Flow Rate
- Feed Rate (mm/s): 32 (default 16)
Note: Make sure Travel Speed Rate (mm/s) = Feed Rate (mm/s)? - Flow Rate Setting(float): 32 (default 210)
Note: Increase the value if the wall too thin, nothing come out from the nozzle or decrease the value if the wall too thick. - Object First layer Feed Rate Infill Multiplier (ratio): 0.4 (default 0.4)
- Object First layer Feed Rate Perimeter Multiplier (ratio): 0.3 (default 0.4)
- Object First layer Flow Rate Infill multiplier (ratio): 0.4 (default 0.4)
- Object First layer Flow Rate Perimeter multiplier (ratio): 0.3 (default 0.4)
- Maximum Z Feed rate (mm/s): 3.0 (default 1.0)
- Perimeter Feed Rate over Operating Feed Rate (ratio): 0.8 (default 1.0)
- Perimeter Flow Rate over Operating Flow Rate (ratio): 0.9 (default 1.0)
- Travel Feed Rate (mm/s): 50.0 (default 16)
- Base Layers (integer): 0 (default 1)
- Interface Layers (integer): 0 (default 2)
- Operating Nozzle Lift over Layer Thickness (ratio): 0.5 (default 0.5, between 0.4 - 0.6 )
Note: First layer height = (operating nozzle lift over layer thickness + 0.5) * layer thickness
e.g. (0.5 + 0.5) * 0.4 = 0.4
Skirt:
- Activate Skirt
- Gap over Perimeter Width (ratio): 5.0 (default 3.0)
- Activate Stretch
- Activate Cool
- Minimum Layer Time (seconds): 15.0 (default 60.0)
Limit
- Maximum Initial Feed Rate (mm/s): 10.0 (default 1.0)
Note: No extrusion if not activated. Fine tune the Extruder Retraction Speed, Retraction Distance and Restart Extra Distance to reduce object strings problem.
- Activate Dimension
- Extruder Retraction Speed (mm/s): 12.0 (default 13.3)
- Filament Diameter (mm): 3.0 (default 2.8)
- Filament Packing Density: PLA 1 (default ABS 0.85)
(e.g. At 0.85 it is going to extrude 1.15mm for 1mm of filament. At 1.15 it is going to extrude 0.85 mm for 1mm of filament. ) - Retraction Distance (millimeters): 0.5 (default 0.0)
Note: Simply tells the extruder not to reverse (toggle) if the start of the next set of extruder moves are closer than this distance, otherwise you may end up with constant tiny extruder toggles if you were doing a highly complicated small print. 2mm is a good figure.?
C:\Users\< USERNAME >\.skeinforge\alterations\ :
Filename: start.gcode
G21; metric is good G90; absolute positioning G92 X0 Y0 Z0 E0; zero the extruded length axesFilename: end.gcode
M104 S0 M140 S0 G91 G0 X-200 Z5 F1000 G28 Y0 G1 Y185 F3000 G04 P6000 M84
Export (default)
- Extrusion Diameter over Thickness (ratio): 1.5 (default 1.24)
Resources:
- Skeinforge parameters for use with Gen6 Electronics
- http://rapmanv3.blogspot.com/2009/09/more-skienforge.html
- http://wiki.makerbot.com/configuring-skeinforge
- http://fabmetheus.crsndoo.com/wiki/index.php/Skeinforge
- http://www.renosis.net/Skeinforge-41-guide.html
- http://code.google.com/p/pif3d/wiki/Skeinforge_Gen6_Tuning
- http://richrap.blogspot.com/2012/01/slic3r-is-nicer-part-1-settings-and.html
Test to print the complete range of practical values for layer thickness/height. Start with 0.55mm through to 0.25mm in 0.05mm steps. All the cylinders are printed single filament wall with PLA and
16mm/sec Feed Rate.
- Layer Height(mm): 0.4,
- Feed Rate (Head Speed): 16mm/s,
- Flow Rate(Extrusion Rate or RPM): 32.7 x 10 = 327
- Perimeter Wall thickness: 0.72
- Layer/mm height: 2.5
- Extruder Retraction speed(mm/s): 12.0 (50.0?)
| Layer Height | Width/Thickness | Feed Rate | Flow Rate |
|---|---|---|---|
| 0.25 | 1.8 | 49.50 | 255 |
| 0.25 | 1.6 | 60.00 | 255 |
| 0.28 | 1.8 | 44.00 | 255 |
| 0.28 | 1.6 | 49.75 | 255 |
| 0.28 | 1.4 | 54.25 | 255 |
| 0.28 | 1.2 | 61.50 | 255 |
| 0.32 | 1.6 | 34.25 | 255 |
| 0.32 | 1.4 | 42.25 | 255 |
| 0.32 | 1.2 | 51.75 | 255 |
| 0.32 | 1.0 | 60.50 | 255 |
| 0.35 | 1.4 | 34.25 | 255 |
| 0.35 | 1.0 | 46.25 | 255 |
Layer Height Calculation:
1mm of height (Z) movement takes 2048 motor steps, a layer height of 0.4mm takes 819.2 motor steps. Not an even number of motor steps, so not ideal.
Skeinforge Profile naming convention
PLA - 0.5mm(N), 1.5mm(H), 1.5(WH), 3.0mm(F)
PLA/ABS, 0.5mm Nozzle, 0.4mm Layer Height, 1.5 Width over Thickness Ratio, 3.0mm Filament
// M80 - Turn on Power Supply
// M81 - Turn off Power Supply
// M302 - Allow cold extrudes
// M400 - Finish all moves
SF49 - Craft Sequence (Template):
Carve -> Scale -> Bottom -> Preface -> Widen -> Inset -> Fill -> Multiply -> Speed -> Temperature -> Raft -> Skirt -> Chamber -> Tower -> Jitter -> Clip -> Smooth -> Stretch -> Skin -> Comb -> Cool -> Hop -> Wipe -> Oozebane -> Dwindle -> Splodge -> Home -> Lash -> Fillet -> Limit -> Unpause -> Dimension -> Alteration -> Export
Carve -> Defines characteristics of the printer.
Scale -> Allows to scale either z axis or x/y axis or both.
Bottom ->
Preface ->
Widen ->
Inset ->
Fill -> Allows to define how an object should be filled
Multiply -> This is used purely to locate the print towards the center of the print layer, on the assumption that STL file X, Y data is centered around the origin
Speed -> Speed is a script to set the feed rate (which means head movement speed in mm/s) and flow rate. The resulting thickness of the filament is a combination of the two plus of the temperature.
Temperature -> If you don't get it right:
- Raft will not stick
- Filament will not even come out or burn
Skirt -> Skirt is a script to give the extruder some extra time to begin extruding properly before beginning the object, and to put a baffle around the model in order to keep the extrusion warm.
Chamber -> Some filaments contract too much and warp the extruded object. To prevent this you have to print the object in a temperature regulated chamber and/or on a temperature regulated bed. The chamber tool allows you to control the bed and chamber temperature and the holding pressure.
Tower ->
Jitter -> Jitters the loop end position to a different place on each layer to prevent the a ridge from from being created on the side of the object.. This tool will change where the layer start - for each layer. As result, you won't see vertical lines. Increase jitter Over Perimeter with to space it out more.
For example if you turn jitter off and print a cube every outside shell on the cube will start from exactly the same point so you will have a visible "mark/line/seam" on the side of the cube. Using the jitter tool you move that start point around hence you avoid that visible seam.
Clip -> Clips stops extrusions early in order to prevent loop plastic build up at the end of a loop and form a bump.
Smooth ->
Stretch ->
Skin ->
Comb -> Moves the extruder around inside holes to prevent stringers in those holes. Comb bends the extruder travel paths around holes in the slices, to avoid stringers. It moves the extruder to the inside of perimeters before turning the extruder on so any start up ooze during travel (points where the nozzle is moving without extruding plastic) will be inside the shape
Cool -> Allows to activate the fan on top with the G-Codes M106 and M107 to turn fan on/off.
It slow down the layers printing if it takes less time than the distribute minimum layer time (i.e. 15 seconds). If a layer prints really fast, it doesn't have enough time to cool before the next layer gets put on top of it. If the printer is trying to put a new layer of plastic on top of a layer that is still very soft, It can lead to other problems such as layer splitting and warping.
Hop ->
Wipe ->
Oozebane -> For DC motors used. Dimensions is for stepper motors
Dwindle ->
Plodge ->
Home ->
Lash ->
Fillet -> Rounding of corners
Limit ->
Unpause ->
Dimension ->
Alteration ->
Export ->
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