Issues converting mesh to t-spline or body

[Anonymous]

I've been attempting to do this conversion for about a week now, with no real results...  Hopefully this is the right place to post this, as it's my first post. I am also kind of new to Fusion.

I've designed a tap handle for our brewery in Maya and after converting triagles to quads, and it's complex... 204,230 faces... 

I need to convert this into a solid to bring to CAM so I can hopefully use a CNC to either carve out a positve model, or at least use a solid model to create a negative casting form.  

Am I to hopeful that this is even possible to convert to a t-spline or body?  I can import the OBJ file and keep all the 'layers' or 'meshes' seperate.  What would be the best way to make this entire model a solid?  Every method I've found on the forums hasn't really worked.  I was able to let it sit for roughly 12 hours and it seems like it converetd everything, but with everything running so slow, I was only able to save it to A360. 

I've attached some screenshots from Maya to show you what the model looks like. 

[James.Youmatz]

Hi @Anonymous,

Welcome to the Fusion 360 Community

First let me start of by saying that is a really cool tap handle! Unfortunately at this time Fusion 360 isn't really equipped to handle that complex of meshes so it may be hard to manipulate the mesh once its in. My guess is that once it converted, Fusion ran real slow. Is there a way you can attack this in pieces? So for example the base as well as the lettering seems pretty straightforward. I'd try to bring those in first and see how it works that way to try and get more comfortable with using the conversion process. The design on the other hand seems really complex and that may be hard to try and convert. One thing you can do is try to reduce the mesh as much as possible. Not sure if you checked out my forum post here, but I posted a quick screencast showing how to go about reducing the mesh in a free software called MeshMixer. Also, another user gives a good tip on how to conert from the mesh to a body pretty quickly.

To be honest, I'm not the most familiar with CAM work, so I can't really give you any suggestions on what method would be best for sending this to CAM. As far as converting this to a solid from a mesh, this may be a difficult challenge, but its worth a shot! You are not too hopeful. Do you mind sharing the file with me at james.youmatz@autodesk.com. Maybe I can reduce the mesh and try to see if I can manipulate it how you want it. 

Thanks,

[Anonymous]

Thanks for the reply James

I'll shoot you a DL link for the file.  

I think I might try exporting different sections of the model into their own OBJ files, then bringing it into Fusion to create a solid to send to CAM. 

[James.Youmatz]

Hi @Anonymous,

Sounds good. I think breaking it up into smaller pieces may work out nicely. I just wanted to let you know that I received your file and I will try to see what I can do with it. Also, I'll try to see if any of the CAM guys have any suggestions as well. There may be a straightforward way to CAM this model that I just don't know about.

EDIT: I spoke with CAM support and it seems that you can use surfaces in CAM. I know of one way to convert the model to surfaces directly which may be able to solve your problem.

I just created a screencast for a different user regarding the same issue. It can be found here, but unfortunately the piece would need to have less than 10k facets :

http://autode.sk/1L7q2pB

Since you don't really want to reduce the mesh and you have already loaded it into Fusion (this may save me 12 hours  of uploading 😞 ) go ahead and try those steps and see if it works. In the meantime if you can get me the file with the seperate parts I can try other methods on my end.

Thanks,

[Anonymous]

James

So far your method you rovided in that screencast is working somewhat flawlessly.  Some meshes I am having trouble converting since I think they are intersecting funny with other newly formed solids, but they can be rebuilt.  So, thanks so far!!

Also, i've tried to produce a toolpath from just the mesh within CAM, and that doesn't work.  Perhaps I am doing it wrong, but I feel I am pretty familiar with that side of Fusion since that's what I first decided to learn after getting the program.  

I'll keep ya updated on the converting.  Exporting the model into several different object files (54 in total, ha), they are much easier to convert. 

[Anonymous]

Awesome to hear you're successfully bringing in pieces of mesh to convert individually, that's kind of a brave new frontier I think for Fusion 360.  I have dabbled with using Meshmixer's unique slicing feature to export one slice of a mesh at a time, then when imported into Fusion and converted to Brep (not Tspline which as I'm sure you found has more limited face capacity), can use Move point to point to assemble slices perfectly back together.  I only wish Meshmixer would have a cool function that would indicate how wide each slice should be to each have near 10,000 faces.  With this slice approach, based on the original face count you mentioned, 'only' 20 slices would be needed 😉

You shouldn't have problems creating CAM operations for a Brep body surface, as someone successfully did in this thread:

http://forums.autodesk.com/t5/design-and-documentation/creating-bas-relief-s-in-fusion/td-p/5794809

Kudos on the patience you have!

Jesse

[Anonymous]

I guess one thing I worried about with bringing in and converting to Brep many 10,000 face meshes in Fusion, is that the cumulative number of faces might significantly impact performance without a serious supercomputer 😉  Will be interesting to hear how you find performance/lagging in Fusion with that many faces.

Jesse

[TrippyLighting]

When you designed this in Maya how did you go about that ?

Maya is a subdivision surface modeler and the control mesh is usually not even close to the 200k+ mesh you have posted.

I don't exactly know how this is done in Maya, but in Blender I'd apply a subdivision modifier to the control mesh and then can choose the level of subdivision I like to match the detail level required. This subdivided end result  after applying the modifier may well be a few 100k mesh, but to export that mesh to Fusion , when I have the low-poly control mesh available would never cross my mind.

If you can export the control mesh then you'll find that converting that into a T-Spline works very nicely with no loss of fidelity.

[TrippyLighting]

Also, something that just occurred to me now after looking at the screenshot in your original post, your model is in no way a single mesh. It is actually several separate meshes. E.g each letter is it's own mesh. The meshes visible in the screenshot, while some are very detailed, do not look like a 200k polygon mesh and also look like quad meshes quite suitable for import into Fusion 360.

[Anonymous]

I've hit a snag.

After importing and converting about 20 single meshes, preformance is incredibly slow.  After each conversion I end up saving, exporting, and then hiding each new BRep. 

But it'll take 10-20 minutes for the open screen to pop up just to insert a new mesh that is only 700kb. 

Blah.  Still going at it though.  The actual STEP file I export is only about 200mb so far.  I've worked with bigger with no issues on preformance.  

Maybe I;ll combinded everything into a single body.  Maybe that'll speed things up. 

[TrippyLighting]

@Anonymous have you had a chance to read my posts ? Your meshes should really not be that high in polygon count. The screenshot you posted in your first post does not look like a 200k polygon mesh.

[Anonymous]

@TrippyLighting I did. The model was built with groups.  The P is it's own mesh, the E is, and so on and so on.  The total face count for the entire model is 204,269.  I'm not terribly familiar with Maya since I personally didn't build the model - my father did who used to work with the program daily for years.  

[Anonymous]

Also, they model was converted to quad meshes prior to exporting each individual section of the model to be more sutible for Fusion. 

[Anonymous]

Yeah I could definitely tell the person that made that mesh is very skilled.

I would be very curious if you can export from Maya some kind of control mesh as Trippy mentions, which I guess has more information at each point, like surface tangency, than just a simple point cloud mesh, hence needing considerably fewer points and being able to have more direct conversion to Tspline.  For conversion of regular mesh to Brep as you're doing, I don't believe quad or try faces really make any difference, except that possibly when you did the conversion in Maya from try to quad my guess is that may have significantly increased face count essentially unnecessarily.   

Have you happened to look at the other popular software like Vcarve I think?  I know there is unfortunately a relatively fair amount of money involved to use that software, but from what I remember it can create CNC toolpaths very readily upon a large imported mesh.

Very interesting though how this will work out.  Like I said the patience it sounds like you have is pretty amazing! 😉

Jesse

[skrubol]

meshcam is an inexpensive ($150 or $200) 3d CAM built for stl files.  Might be worth an eval to see if it'll work.

It's pretty basic CAM, but it's also pretty simple.  It's what I used for my 3d work before fusion.