topic A too complex mountain? in Fusion Design, Validate & Document Forum

A too complex mountain?

mailNJU7B — Sat, 12 Dec 2020 15:25:05 GMT

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

Re: A too complex mountain?

g-andresen — Sat, 12 Dec 2020 15:40:06 GMT

Meshmixer?

günther

Re: A too complex mountain?

mailNJU7B — Sat, 12 Dec 2020 15:46:26 GMT

I tried but it hangs too after 2 minutes. 😞

Re: A too complex mountain?

hfcandrew — Sat, 12 Dec 2020 16:08:05 GMT

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?

Re: A too complex mountain?

g-andresen — Sat, 12 Dec 2020 16:11:05 GMT

Hi,

280 MB is not exactly small.

This is also critical for other applications.

günther

Re: A too complex mountain?

hfcandrew — Sat, 12 Dec 2020 17:06:00 GMT

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

Re: A too complex mountain?

mailNJU7B — Sat, 12 Dec 2020 20:18:52 GMT

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

Thanks

Re: A too complex mountain?

hfcandrew — Sat, 12 Dec 2020 20:34:39 GMT

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.

Re: A too complex mountain?

mailNJU7B — Sat, 12 Dec 2020 21:45:07 GMT

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.

Re: A too complex mountain?

TrippyLighting — Sun, 13 Dec 2020 11:48:36 GMT

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

Re: A too complex mountain?

mailNJU7B — Sun, 13 Dec 2020 17:05:34 GMT

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

Re: A too complex mountain?

mailNJU7B — Sun, 13 Dec 2020 17:09:07 GMT

I have only the obj, no other file format.

Re: A too complex mountain?

hfcandrew — Sun, 13 Dec 2020 20:11:03 GMT

Strange. Well see attached.

Re: A too complex mountain?

mailNJU7B — Sun, 13 Dec 2020 20:20:43 GMT

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?

Re: A too complex mountain?

TrippyLighting — Mon, 14 Dec 2020 02:27:16 GMT

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?

Re: A too complex mountain?

mailNJU7B — Mon, 14 Dec 2020 08:28:48 GMT

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.

Re: A too complex mountain?

hfcandrew — Tue, 15 Dec 2020 00:35:19 GMT

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

Re: A too complex mountain?

GRSnyder — Tue, 15 Dec 2020 09:18:09 GMT

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.)

Re: A too complex mountain?

mailNJU7B — Wed, 16 Dec 2020 15:14:08 GMT

Thanks.
I'll try also this method.