A too complex mountain?

[mailNJU7B]

Hi all,

I have an OBJ (281MB) of a mountain profile than I would like to print in 3D.

I tried to import the obj and then convert to B-rep but it is too complex. I tried to simplify reducing the mesh faces but my computer hangs.

Any hint on how to simplify or convert this obj?

Thanks in advance.

Walter

[g-andresen]

Hi

Meshmixer? 

günther

[mailNJU7B]

I tried but it hangs too after 2 minutes. 😞

[hfcandrew]

This model is quite low quality in its accuracy/contours, with a needlessly high triangle count of 522,242 when it it could be reduced to about 10,000.

Software has trouble reducing it because this is not one continuous shell, it has thousands of shells.

It was in improper export to .stl. Where did you get it from? 

[g-andresen]

Hi,

280 MB is not exactly small.

This is also critical for other applications.

günther

[hfcandrew · Accepted solution]

Here, follow these steps in MM: https://autode.sk/348NR3F

[mailNJU7B]

Got it from a friend. I'll ask him to export in a simple way.

Thanks

[hfcandrew]

I sent that video if you wanted to know what to get and customize it yourself, if not I can just send you my version.

[mailNJU7B]

Hi, first thanks for your video. I followed your steps but it seems that nothing happens when I try to reduce at 95%.

I tried several times but no action on reduce. I do not understand what I'm doing wrong.

[TrippyLighting]

This .obj clearly started as a quad-mesh.

Then a simple subdivision (as opposed to a Catmull-Clark subdivision) was applied that then the mesh was triangulated.

IF you have access to that un-triangulated mesh, or the original quad mesh, then the result you are looking for is going to be much better.

I'd not be surprised if that original quad mesh was created by an online tool such as TouchTerrain

[mailNJU7B]

Yes please, if you can send me your version it's a great hel for me. Thanks

[mailNJU7B]

I have only the obj, no other file format.

[hfcandrew]

Strange. Well see attached.

[mailNJU7B]

Thanks a lot!

I tried to export from Meshmixer just before the reduce command. Then I reduced in FUSION360 and it worked. I obtained the same result as your. I think that is a memory problem of Meshmixer on Max. I will also try on a PC.

Now if I want to work with this mesh in FUSION360 I should convert it in a T-Spline?

[TrippyLighting]

How would you propose to convert a triangulated mesh into a T-spline in Fusion 360?

Why would you need to convert it into a T-spline?

[mailNJU7B]

Be patient with me, I'm new with this world. I'm "playing" with Fusion360 since 2 weeks and it's a whole new world.
My goal is to 3dprint the small mountain (the big .obj) on a solid rectangular base (a christmas gift for a friend of mine) and I can't find a way.

I'm able to build objects with Fusion360 but is the first time that I deal with a mesh. Thanks a big help I'm now with a simplified mesh in Fusion360.

I know there is a lot of things I must learn.

[hfcandrew]

You're going to have to learn a lot about CAD software and slicer software before you get to 3D printing anything.

You'll have to make a solid manifold single shell mesh out of that.

As a general rule use Meshmixer if working with meshes. Use Fusion360 for everything else.

To make this have a printable with a base, select all and extrude: http://help.autodesk.com/view/MSHMXR/2019/ENU/?guid=GUID-EC66F60C-40E4-4082-B236-A69395D1CAAF

[GRSnyder]

Quad Remesher (run in Blender) also cleans this right up.

The triangles in the original mesh seem to have been written out separately, so there are a lot of duplicated vertices and edges. Just fixing that (again in Blender, with Mesh -> Clean Up -> Merge by Distance) reduces the mesh complexity significantly.

The attached terrain.obj file is a quad mesh, so it should convert directly to a T-spline and thence to a surface in Fusion 360. Add bounding planes and then use Boundary Fill to convert to a solid. (Or just Thicken the surface.)

[mailNJU7B]

Thanks.
I'll try also this method.