cura bridge settings

[3blake7]

im only 2 months as a 3d printer but im loving it! i really appreciate your contributions to cura, especially the bridge settings. ive been wanted to get more involved with contributing to opensource, which ive benefited from so much over the years.

i had some questions if you dont mind.

is bridge skin density implemented? i edited the cura gui to increase the maximum so i could go above 100% but it didnt work and i was looking at curaengine and i couldnt find that variable being used anywhere. i was hoping to create some overlap with the skin lines, so they would fuse together. i was sort of able to do this by lowering my line width by alot but just want it for bridge skins, not the whole print.

i also tried updating LayerPlan.cpp, added a new variable overhang_fan_speed and set it to settings:bridge_fan_speed, then added it to the three addExtrusionMove after overhang_speed_factor. didn't work, guess i need to wrap my head around all the code better :D my goal was to use more fan on overhangs when using PETG, which has a habit of curling up if you dont cool it, but didn't want to cool everything since it reduces layer adhesion.

thanks!

[smartavionics]

Hi, glad you appreciate my tinkering.

is bridge skin density implemented? i edited the cura gui to increase the maximum so i could go above 100% but it didnt work and i was looking at curaengine and i couldnt find that variable being used anywhere. i was hoping to create some overlap with the skin lines, so they would fuse together. i was sort of able to do this by lowering my line width by alot but just want it for bridge skins, not the whole print.

Yes, it is implemented (see FffGcodeWriter::processTopBottom())

i also tried updating LayerPlan.cpp, added a new variable overhang_fan_speed and set it to settings:bridge_fan_speed, then added it to the three addExtrusionMove after overhang_speed_factor. didn't work, guess i need to wrap my head around all the code better :D my goal was to use more fan on overhangs when using PETG, which has a habit of curling up if you dont cool it, but didn't want to cool everything since it reduces layer adhesion.

I don't see why you need to do this when you can just set Overhanging Wall Fan Speed ?

[3blake7]

I don't see why you need to do this when you can just set Overhanging Wall Fan Speed ?

dont see that setting, just overhang angle and overhang print speed

[smartavionics]

Perhaps you're not looking at the right branch or the most recent code?
All my development is tested on the mb-testing branches and all my releases are built from the mb-master branches.

[smartavionics]

Actually, the mb-testing branches are not often pushed to github so I would only use the mb-master branches if I were you.

[3blake7]

im using the one that cura-build downloads, ill get yours! thanks

[smartavionics]

I have my own cura-build and cura-build-environment repos and in those you also need to use the mb-master branches.

[smartavionics]

If you use my cura-build and cura-build-environment repos, to build you must do the following in both repos...

mkdir build
cd build
../run-cmake.sh
make

[smartavionics]

I install everything in /opt/cura so you need to be able to write that directory (i.e. change it to your ownership).

[3blake7]

cool, just compiled it and i have overhang fan speed now!

[smartavionics]

Great!

[3blake7]

i tested PETG with overhang fan speed and it does help, but it still curls up unless i have the fan on for the whole print, albeit it doesnt need to be as high now. maybe an option to include overhang fan speed for inner walls of an over hang too? just a thought

[smartavionics]

maybe an option to include overhang fan speed for inner walls of an over hang too? just a thought

Sounds simple but due to how Cura works I think it would be more work than is justified.

Where it curls up, is there a bottom skin being created? If so, it may be worth playing with the bottom skin expand/shrink settings to try and remove any bottom skin that is on/near an overhang.