Orientation edges mesh

Hi everyone,
I have a problem with a job on Grasshopper.Cattura
I would have to orient the edges below 45 ° of this foam, to print additives in manufacturing.
Is there any function to do this?
Thanks.

1 Like

Is this network coming from the edges of Voronoi cells?
and if so, how are you distributing the points before this?


The start and end points of the edges are pulled out and then evaluated if they are outside the assigned geometry.

You will have to post a Grasshopper file if you want anyone to help in this case…

Foam_stochastic_FILE.gh (24.4 KB)

45° to what reference?

The XY plane.

I still don’t understand which edges you want to analyse / orient?

Maybe a sketch would help?

I would like to orient the foam uprights above 45 °, so as not to require support when printing!
Like this!InkedCattura_LI

Ok, you want to do that for all ends?

1 Like

Yes, exactly!

I would print this using an online service like iMaterialise.com on one of their laser sintering printers as these do not require support material.

If you manage to print this on a FDM printer it will be a small miracle! There will be support material everywhere. You don’t just need to identify the >45degree surfaces, you need to identify those with >45degree surfaces above them as these will need supporting to then support the surfaces above them. Unless you have a top of the range FDM printer you will print a big ball of spaghetti or be in line for a sainthood for performing miracles! I could be wrong, perhaps FDM 3d printers have improved massively in the last couple of years.

My advice is save yourself hours of design and simply order it from iMaterialise.com. At least get a quote if you can save the model as a valid STL file.

Good luck :slight_smile:

2 Likes

Thanks for the information, but I will print on highly professional machines, which require you to orient the edges to waste less material. Is it possible to do it in any way?
Thanks.

Well it sounds like you need to change your design so no parts are greater than 45deg to the print plane so they don’t need support material. You probably need to do this right at the start of your design process where the foam structure is generated. Perhaps using something like Kangaroo.

A shame to be forced into such a compromise when you can just print this on a more suitable print technology tho.

You will also have to pay attention to the thickness of each foam section because very thin sections are difficult to print.

Wouldn’t it be possible to orient the end points of each edges? Thank you!

I don’t know how you could do it other than adding some sort of constraint when the foam structure is generated as I presume it is generated from a network of lines that are thickened to create the foam structure. When the line network is generated you could check the angle of each line and elevate the higher endpoint if the angle is <45degrees.

I do not know how you could do this after the line network has been changed to a thickened mesh. If you have not generated this foam from a line network and only have the mesh as shown in your image then I think what you are trying to do will be very difficult.

Also, if you need to adjust the ends of the foam structure (i.e. the free ends that do not connect to anything else) to avoid them needing support during the 3d print process then I imagine you will also have to adjust every “strut” within the foam structure too because any part of that structure that overhangs more than 45 degrees will need support material to print well.

From my experience with 3d printing, this type of structure is not well suited to FDM 3d print processes (i.e. Fusion Deposition - where the printer extrudes a filament to print the part layer by layer and each layer requiring support material to print on if it overhangs the previous layer by more than 45degrees). Parts with thin sections can warp as the print material cools so subsequent layers do not print exactly in the right place.

Plastic laser sintering processes are good for this type of structure because the powder they use supports the whole part anyway. This allows any angle of overhang.

Metal laser sintering processes, although very similar to plastic, do need support structures for stability I believe. (I have no experience of metal laser sintering)

The Stratasys and HP polyjet technology printers could print something like this but if you can afford this process you wouldn’t be worried too much about the cost of the support material. If you are concerned about the different surface finish that you get on supported surfaces versus un-supported surfaces then the Stratasys system can coat the whole model in support material so you get a matte finish all over instead of supported surface being matte and unsupported surfaces being gloss.

What printer will you print this structure on?

I honestly think your best option is to print on a suitable process because you may have to compromise and change the design of the part to print it on a process that requires support material.

The printing process will most likely be Laser Powder Bed Fusion. The structure was generated using a DeconsturctBrep from Voronoi3D.

OK… metal powder?

@DanielPiker gave you a clue above…

When you deconstruct brep to get the line network you might be able to use Kangaroo to avoid angles that are too overhanging for that print process.

There is an angle goal in Kangaroo. I have not used that before. Perhaps research the angle goal, try and see if you can use Kangaroo to manipulate the line network before it is thickened. If you post a definition then people can help you with it.

Yes, metal powder. I try to utilise this function.

Hi -

The metal powder will likely provide the necessary support to print overhangs. You might want to double-check the 45° requirement with the provider of that service before trying to modify your model.
-wim

1 Like