# Specific 3D Printers, Scanners, & Hardware > RepRap Format Printer Forum > MakerFarm Forum >  i3v Cura settings

## dacb

After struggling with Slic3r, I've moved to Cura.  I enjoyed Slic3r's exquisite control over parameters, but other issues led me away from it.

In addition to sharing them, I was hoping for feedback on my medium quality Cura settings.  These are for a 10" i3v w/ 1.75mm x .4mm hexagon head and ABS.  Use at your own risk.  Sufficiently indemnified, here goes:
The retract parameters are based on comments somewhere about here. Temperature is from experiment with MakerFarm vendor glow in the dark green ABS. To help deal with curling of the finished piece, I've been using a brim. The travel speed is probably too low at 100 mm/s. Bottom layer is slow (20mm/s) and fat. Infill is roughed out at 100 mm/s and most printing occurs at 70 mm/s (mostly based on ideas from printbus).

This is a starting point. For each object I print in Cura, I go through a mental checklist and tweak parameters such as infill, wall thickness, brim, support and speed.




> [profile]
> layer_height = 0.2
> wall_thickness = 0.8
> retraction_enable = True
> solid_layer_thickness = .8
> fill_density = 25
> nozzle_size = .4
> print_speed = 70
> print_temperature = 240
> ...

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## DanSilov

Thank you, will try later to see how it works for me.

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## printbus

> ...The retract parameters are based on comments somewhere about here. Temperature is from experiment with MakerFarm vendor glow in the dark green ABS. To help deal with curling of the finished piece, I've been using a brim. The travel speed is probably too low at 100 mm/s. Bottom layer is slow (20mm/s) and fat. Infill is roughed out at 100 mm/s and most printing occurs at 70 mm/s (mostly based on ideas from printbus)


I just think the neighborhood of 70mm/s is a good compromise between speed and printer noise/print quality.  Simple flat surfaces and boxes I do print up to 100mm/sec.  

I think we have work to do to optimize the retraction settings; retraction_minimal_extrusion in particular.  I've had to turn retraction off on some prints in order to keep repeated retraction from grinding into the filament.  Their default of 0.02mm for retraction_minimal_extrusion seems awfully small; I'm currently trying 0.5mm.  Likewise, I've increased retraction_min_travel from 1.5mm to 5mm to reduce the number of retractions.  I'm also following their field comment and run retraction_hop set to 0.075mm to minimize ooze smearing across a print during a move. 

It'll be interesting to eventually prove whether layer0_width_factor does anything. I had mine set to 250% to mimic my slic3r settings.  Skimming through forums before I adopted Cura, the Cura developer was steadfast against implementing the slic3r-like setting, but he was under a lot of pressure to do so.  I remember a post where he basically said "fine, it's in the gui. But people are going to have to write their own script for it".  Coincidentally or not, this is the one standalone Cura setting that doesn't appear to be accessible in Repetier-Host.  

I know you're running with brim, but I set the skirt_line_count to 2.  That usually gives me enough time to tweak thumbwheels on the Y-bed if I want to after seeing how the skirt is turning out.  

It wasn't really clear to me what the "fix horrible" settings are trying to do.  I've only ran with them all set to false.  

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Overall, I've grown to like how Repetier-Host handles the settings for Cura.  With standalone Cura, I seemed to always be befuddled on where to find settings. "Maybe basic. Well, I don't see it. Advanced? Nah.  Must be in the expert settings - oh yeah, I have to go to the top menu to pull those up.  Nope. Must have missed it on one of the other two groupings..."  The functional groupings RH has makes more sense to me.  For print speeds, configuration details allow you to set up min and max values for all the speeds.  In the main slicing pane, you then have a short set of obvious stuff to set - sort of like your checklist.  Pick the bed adhesion between brim/raft/none (none will give you skirt). Pick from the predefined print quality options you set up (I only have 0.2mm set up).  Set support to none/touching everywhere/touching bed.  Drag a slider to set the basic print speed from the range you've defined.  Check/uncheck print cooling management.  Drag a slider to set the infill percentage.  Pick from the predefined filament profiles you set up. Slice. Start Print. 

 I do have a downside to RH - with Slic3r and standalone Cura, I used to always grab a copy of the ini file to archive with the print stl and gcode files.  RH has multiple ini files that reflect the detailed configuration setup, but I haven't seen a way to archive the final selections actually made on that slicing pane.

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## dacb

What were the signs during extrusion that the filament was being ground up by repeated retractions?  I'm guessing this is also work-piece specific issue.  I would like to find a way in the Cura visualizer to flag / highlight the retractions in the toolpath view.  

Your idea about the skirt line is great.  I'm using a brim because I've been having terrible problems with the ABS pulling up and the brim + ABS slurry directly on the plate seems to be working.  I would definitely turn this off for PLA.  

My understanding is the fix horrible type A is enabled by default and I didn't mess with those settings.  From what I read they involve interpreting geometries from the STL and the type A is generally a good thing but can close some holes that were intended to be left open.

As for Repetier-Host... I'm intrigued, but the Mac version wasn't stable when I gave it a brief go and I didn't see Cura support (the Mac version is way behind IIRC). Sadly, the linux version requires a version of mono that conflicts with what I need to run my CAM tools.

Separate from the slicing, I had been using Octoprint on a Raspberry Pi for control, mostly for the web cam (which is really just a wrapper for MJPG streamer).  It works for simple manipulations (move Z up, etc.) and for monitoring / setting temperatures, but all of the other features, e.g. starting a print, uploading to SD card, visualizing GCode don't seem to work out of the box.  Anyway, since it isn't completely functional, I moved over the Repetier-Server.  I'm not in love with the web interface, e.g. it doesn't have a temperature graph, but I've only had it up and running for less than a day so I'll reserve judgement.  All I really want is to be able to send files to the printer without sneaker-netting the SD card around the house.

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## printbus

> What were the signs during extrusion that the filament was being ground up by repeated retractions?  I'm guessing this is also work-piece specific issue.  I would like to find a way in the Cura visualizer to flag / highlight the retractions in the toolpath view.


The indicator was that the extrusion would just stop, and when I'd abort the print and pull the filament, the hobbed bolt had chewed into it.  Everything would go fine for a while again after reloading the filament and restarting. This is definitely work-piece related. The recent print where I battled this was on a 4-in x 4-in project box with 1-inch high sidewalls.  Posts with screw holes for a lid in the four corners.  At some point in the sidewall layup, the extrusion would just stop. Predictably.  Took a while to rule out bad filament, too-low temperature, too much cooling fan airflow, too much spring tension on the extruder, etc.  I eventually realized that corner-to-corner moves were involved in Cura completing the screw posts in the corners, with a retraction on each move.  The filament apparently couldn't hold up to  the repetitive action of the hobbed bolt rotating back and forth for the retractions over such a short length of filament.  

I'm not aware of a way to explicitly view the retractions in Cura.  You can see travel moves, and indirectly perceive a retraction for each move longer than the retraction_min_travel setting.   When I want to really see details in the slicer output, I usually bring up the gcode in http://gcode.ws/ and look at layer info. Slider bars allow you to select different layers and follow the nozzle move around the layer. 

Actually, it was viewing the slicer output in gcode.ws that finally told me what was happening with the box.  I had both print and travel speeds at 100mm/sec, and watching it print I just assumed the multiple loops around the print were just printing the wall.  As soon as I saw the corner-to-corner travel I realized what was probably happening. 

Cura was only recently added to Repetier Host as part of their v1.0 baseline - maybe a month ago.  Understood on the Mac and Linux constraints.

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## dacb

> I'm not aware of a way to explicitly view the retractions in Cura.  You can see travel moves, and indirectly perceive a retraction for each move longer than the retraction_min_travel setting.   When I want to really see details in the slicer output, I usually bring up the gcode in http://gcode.ws/ and look at layer info. Slider bars allow you to select different layers and follow the nozzle move around the layer.


Good stuff, thanks.  Are you using PLA or ABS?  Would it matter for retraction, e.g. the material reacts differently to being push-pull-pushed at temperature?

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## dacb

> I do have a downside to RH - with Slic3r and standalone Cura, I used to always grab a copy of the ini file to archive with the print stl and gcode files.  RH has multiple ini files that reflect the detailed configuration setup, but I haven't seen a way to archive the final selections actually made on that slicing pane.


Hey, I don't think I properly acknowledged how important this point is.  Independent of any tool, I believe reproducibility of prints is an absolute must have.  Thanks for bringing this up.

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## printbus

The project box was in PLA, but I've had similar problems in both PLA and ABS.  I had already learned to turn off retraction if there are lot of very short segments (legs, posts, etc.) involved in a print, but the corner-to-corner travel on that box had me fooled.  I edited the post to explain how I had travel and printing both set to 100mm/sec, so I didn't realize that some of the movements were just travel (why didn't I look at the extruder gear??).  That box was probably on my "worst" spool of PLA for this. It is softer and more pliable than my other PLA and ABS, and it's undersized in diameter.  Variables like that are probably more significant than PLA vs ABS.

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## dacb

> ...
> I'm not aware of a way to explicitly view the retractions in Cura.  You can see travel moves, and indirectly perceive a retraction for each move longer than the retraction_min_travel setting.   When I want to really see details in the slicer output, I usually bring up the gcode in http://gcode.ws/ and look at layer info. Slider bars allow you to select different layers and follow the nozzle move around the layer. ...


I've gone back to OctoPi after a rough set of prints.  I noticed that the most recent OctoPi from github supports a GCode viewer that shows retractions and their pause points.  See attached screenshot (red dots).

octopi.jpg

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## printbus

> I've gone back to OctoPi after a rough set of prints.  I noticed that the most recent OctoPi from github supports a GCode viewer that shows retractions and their pause points.  See attached screenshot (red dots).


I assume OctiPi gives you the same functionality of OctiPrint, just running on a Pi? Some research revealed OctiPrint uses the same gcode.ws viewer.  Nice.  Do you have the option to see what the resulting print speeds are for different parts of the layer? That's the other thing I go to gcode.ws for, but I don't see that in the snapshot.

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## CoffeeCup

> I think we have work to do to optimize the retraction settings; retraction_minimal_extrusion in particular.  I've had to turn retraction off on some prints in order to keep repeated retraction from grinding into the filament.  Their default of 0.02mm for retraction_minimal_extrusion seems awfully small; I'm currently trying 0.5mm.  Likewise, I've increased retraction_min_travel from 1.5mm to 5mm to reduce the number of retractions.  I'm also following their field comment and run retraction_hop set to 0.075mm to minimize ooze smearing across a print during a move.


Printbus what you set your Cura settings at compared to what my settings for Slic3er are here's some observations. 
Looking at some settings MakerFarm provides out of the box for Slic3r there is a retract_length and it's set to 1 (mm I imagine). In Cura I see there is a retraction_amount and it's set to 2.

Next in Slic3r settings there is a retract_before_travel setting and it's set to 2. I could not find an equivalent to Cura's retraction_min_travel in Slic3r.

Here's some assumptions I have: Cura's retraction_min_travel means it will retract if it travels at least as far as it's setting 1.5mm (5mm in your case). Slic3r's retract_before_travel means it will retract it's setting of 2mm before each travel.


I wasn't unhappy with the settings that MakerFarm provided out of the box for Slic3er I'm just unhappy with Slic3r's slicing itself. So since Slic3er does not have an equivalent to retraction_minimal_extrusion it seems and their retract_before_travel setting is set to 2  I think meeting in the middle is a good compromise for now.

I'm planning on setting retraction_minimal_extrusion to 1mm. I plan to set my retraction_min_travel to 5mm as you did. I'm curious how has your  retraction_minimal_extrusion and retraction_min_travel settings worked out for you?

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## printbus

> ... I'm curious how has your  retraction_minimal_extrusion and retraction_min_travel settings worked out for you?


As mentioned elsewhere, I haven't used Cura for the last 8 months.  IIRC, the values mentioned were good starting points.  What I can say is that I grew to feel that retraction is part of the settings that are possibly best tweaked for each print, trading off print quality and the risk of print failure due to the hobbed bolt chewing into the filament. Before starting a print, I'd often view the gcode result layer by layer in gcode.ws, looking to see what the gcode was doing as far as print speeds, travel speeds, how often the gcode was switching between print and travel moves, and how many of those transitions would involve a retraction. I'd then readjust settings to resolve anything I didn't like in the gcode result, and slice the part again.  Deciding what to change just came with experience. 

I'll also add that I learned a lot about slicer settings in experimenting with how to improve my print results for thread MakerFarm benchmark results with Make: 2015 Shoot Out test models.  Experimenting is a powerful way to learn.

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