Brim flow

[Strijar 0]

Hello! I want to add a flow to the brim. It is logical to assume that it is located on the first layer. But the addition of flow on the first layer does not give any result for the brim! I use Flex, and the brim is not very strong.

Edited June 15, 2018 by Strijar

[burtoogle 516]

Looking at the code, the flow for the skirt and brim is controlled by Initial Layer Flow setting.

[Strijar 0]

In this photo the flow for brim is 120%. Does this look like 120%? But the flow of filling (in right part) is 115%. That's like 115%

[burtoogle 516]

Do you read C++, if so, here's the proof:

        skirt_brim_config_per_extruder.emplace_back(
                PrintFeatureType::SkirtBrim
                , train->getSettingInMicrons("skirt_brim_line_width")
                    * ((storage.getSettingAsPlatformAdhesion("adhesion_type") == EPlatformAdhesion::RAFT) ? 1.0 : line_width_factor_per_extruder[extruder_nr]) // cause it's also used for the draft/ooze shield
                , layer_thickness
                , (layer_nr == 0)? train->getSettingInPercentage("material_flow_layer_0") : train->getSettingInPercentage("material_flow")
                , GCodePathConfig::SpeedDerivatives{train->getSettingInMillimetersPerSecond("skirt_brim_speed"), train->getSettingInMillimetersPerSecond("acceleration_skirt_brim"), train->getSettingInMillimetersPerSecond("jerk_skirt_brim")}
            );

Just kidding! How about this, let's play spot the difference...

 

 

 

So it looks from the code and the layer view that the brim is influenced by the initial layer flow.

 

[gr5 2,269]

Bottom layer will be affected by the flow but also by the leveling height.  I prefer manual leveling so I can get consistent results.  Those brims in the photo look about 10% underextruded.

 

Also the print speed and temperature affects things because that affects the pressure in the nozzle and flexible filaments compress a lot more so it's harder to get the higher pressures and higher flow rates as you go faster.  Typically cura slices the bottom layer around 0.3mm which may be double or triple your other layers so it's good to print correspondingly slower to get the same volume through the same tiny nozzle in the same amount of time and not expect the printer to be able to print much higher volumes on the bottom layer.

[Strijar 0]

On 6/16/2018 at 11:01 PM, smartavionics said:

Do you read C++, if so, here's the proof:

It looks convincing.

[Strijar 0]

23 hours ago, gr5 said:

Bottom layer will be affected by the flow but also by the leveling height.  I prefer manual leveling so I can get consistent results.  Those brims in the photo look about 10% underextruded.

 

Yes, that's it! In this case, the model itself on the bottom layer is printed normally.

I use 0.1mm for bottom (Other layers 0.2mm, nozzle 0.4mm)

[gr5 2,269]

If that's supposed to be a 0.1mm bottom layer thickness then you should rotate the 3 leveling screws CCW as seen from below to move the bed up a little.  About 1/3 turn.  And if auto leveling is on I'd turn it off but that's my workflow.  Other people are fine with auto leveling.