Tree supports see too flimbsy

[benclewett 0]

I'm trying to use the new tree supports in version 5.4.0-beta.1

 

However they seem too flimsy.  They don't adhere to the bed and easily distought.  There were three in the attached picture, but as you can see, only one (top left) is surviving and I'm not 10% into the print.  One is gone totally, and the other is hanging on by a thread.  How can I make these supports with better bed adhesion, like a brim, and a bit stronger?

 

Thanks

[GregValiant 1,351]

If the model isn't proprietary use the "File | Save Project" command and post the 3mf file here.

I typically run Support Flow and Support Interface flow at 90% to make them weaker and it prints fine and the support does break out easier.  I'm thinking you either have a flow issue or poor layer adhesion.

What material is that?  Silky PLA has inherently poor layer adhesion and generally needs to be printed at higher temps.  In my case that's 215 instead of my normal 205.

[benclewett 0]

3mf attached.

 

The PVA is standard PVA, the model builds fine.  It just seems to me like the feed rate for the tree supports is too fast so not enough PVA in the structure, and they need a brim to give them better support.

 

But very glad to see the tree support, much needed in Cura.

with_tree_support.3mf

Edited July 14, 2023 by benclewett

[GregValiant 1,351]

When Cura paints models in Polka-Dots it means that surfaces are in error.  Since you aren't printing in Surface Mode or Spiralize I'm surprised it sliced.  I could only get the shorter piece to slice.

 

I generated a gcode of the short model and analyzed the file.  All the supports are going down at .40 line width.  Other features (Inner Walls, Skins, etc.) are variable, but the Support is consistent at 0.40.  The print speed for all the support extrusions is 50mm/second.

So I don't see a Speed or a Flow issue.  I don't have a multi-extruder printer so I won't comment on PVA.  Maybe @gr5 has some thoughts on that.  (I have read that it sucks up moisture like a sponge.)

 

Edited July 14, 2023 by GregValiant

[benclewett 0]

Thanks for looking.  Yes the model is terrible, but it did slice and print.

It seems to have worked for you, so I don't know why my trees didn't stick to the base and grew with holes in the sides.

 

When I print with, say, zig-zag traditional support, the support walls seem thicker, and they print onto a base or mini-raft adhering better to the printer bed.  Which seems to give it a structural strength I don't seem to be getting from the tree.

 

Is there any way I can tune the settings for the tree structure?

[GregValiant 1,351]

You can try increasing the "Support Flow" or the "Support Line Width".

When traditional supports get taller, each layer is square on top of the one below.

When tree supports grow, each layer can be offset from the one below so there just isn't as much contact.  You could play with the Branch Angles and other settings to get the tree to grow more upright.  The downside to that is they don't reach as far.