UltiMaker Cura Alpha 🎄 Tree Support Spotlight 🎄

[NTwoO 5]

Ah! Sounds perfect! I'll check it out sometime.

[NTwoO 5]

In the tree algorithm I see some peculiar behaviour. This is a close up of the Charybdis keyboard model. Small notches are visible in the close up below.

 

 

Slicing this with a tree support shows these little branches(leaves?) in these gaps. Ramping up the minimum support size doesn't prevent this,

 

Is there a way to prevent this?

 

Adding support blocks does fix this, but it would have been nice if this could be managed with a parameter.

Edited April 6, 2023 by NTwoO

[CasperLamboo 0]

Hi @NTwoO, That seems like an interesting usecase and I can I can imagine you don't want support in these cases. One setting that might help here is "support horizontal expansion". If you set this to a negative value support will not be generated on these small edges. I don't have your model so I cannot experiment with settings on your model. I do however have a similar model and setting the "support horizontal expansion" setting to a value of "-0.4" removes the support on these small edges as expected. Let me know if this works for you!

[NTwoO 5]

The horizontal expansion is only present if I use normal support. With the tree mode I could not find it.

[GregValiant 1,273]

You can switch to "Normal" support, set the "Support Horizontal Expansion" and then switch back to "Tree" supports and it should work.

This is from the "support_offset" setting in fdmprinter.def.json:

"enabled": "(support_enable and support_structure == 'normal') or support_meshes_present"

and this is from the "support_interface_offset" setting

"enabled": "support_interface_enable and (support_enable or support_meshes_present)"

 

The result is some confusion.  "Support Horizontal Expansion" is not available when "Tree" support is enabled, but "Support Interface Horizontal Expansion" IS available even though it can't be set if "Support Horizontal Expansion" is set to "0" which can't be changed because it isn't available.  

[Cuq 202]

I understand the difference between :

 

Support Placement : Everywhere  + Rest placement : Force Only BuildPlate

 

&

 

Support Placement : Touching BuildPlate 

 

But Force Only BuildPlate Should be define as Use BuildPlate as possible

 

Note : Cura Alpha 5.4

 

Edited June 1, 2023 by Cuq

[MariMakes 199]

Hey @Cuq,

 

I recall that we were having a hard time finding a good name for these settings. So I think the team is open to a good alternative if you have one.

Can you help me understand, what you are trying to suggest?

Which of these settings do you think deserve a change, and why?

Rest Preference
The preferred placement of the support structures. If structures can't be placed at the preferred location, they will be placed elsewhere, even if that means placing them on the model.
"Force Only Buildplate" or  "On Model If Necessary"

Support Placement
Adjusts the placement of the support structures. The placement can be set to touching build plate or everywhere. When set to everywhere the support structures will also be printed on the model.
"Touching Buildplate" or "Everywhere"

[Cuq 202]

Support Placement : "Touching Buildplate"

 

On this example some area are not supported because of the Maximun Branch Angle limitation, and it's normal.

 

Now if we switch to the Support Placement : "Everywhere" + Rest placement : Force Only Buildplate   we have this result : 

 

 Some of the support trunk start from the Model : So despite we have requested "Force Only Buildplate" We got some support starting on the model . So that's why I say you should not call this option "Force Only Buildplate" but "On Buildplate as possible" 

 

Now if the use the option : "On Model if Necessary"  we have this result :

 

 

In this case it's not "On Model if Necessary" because has the have seen in the previous image, We have the possibility to get a result where some trunk start from the Buildplate so it's not Necessary  but  Required ?

 

So I would prefer : 

 

Support Placement : Touching buildplate. Support will be created only from the buildplate, And if it's not possible due to branch parameter limitations, we will not have any support for the unreacheable area.  

 

Support Placement : Everywhere

• Rest Placement : On buildplate as possible . Support can be created everywhere but as much as possible starting from the buildplate and in some case we can have some support starting from the model.
• Rest Placement : On model if required , support can be created everywhere and if required you can have support starting on the model. And Sometimes Required means they start on the model because you have more direct or simple support if you start on the model.

 

And concerning Rest Preference , yes it's not really explicit;  Positioning Refinement ?

 

Edited June 5, 2023 by Cuq

[GregValiant 1,273]

My 2 cents...

 

Support Placement : 

Everywhere

On the Build Plate only

Only include supports that can grow from the build plate

On the Model only

Only include supports that grow from the model.

[Cuq 202]

Cura Alpha 5.4 Testing 105

 

 

The problem with the Support Horizontal Expansion parameter reported by @GregValiant is still present. If the Tree Support option is activated, this parameter changes the result of the supports, but it is not visible in the parameter list.

 

Support with a Support Horizontal Expansion = 2mm

 

 

Support with a Support Horizontal Expansion = 0mm

 

 

Edited June 7, 2023 by Cuq