Rhino6 very slow exporting mesh

So I created a model of an engine bell for a spaceship.it was done as separate closed solid polysurfaces and the I used boolean union to join everything together.On my Alienware r7 laptop the union process was pretty slow.it took up to 15 minutes to union each additional polysurface to the main engine bell.When I tried exporting the model as an .stl for printing rhino6 became non-responsive after trying to create the mesh after about 15 minutes. Is there a setting in Rhino6 that I can adjust to speed up this process or is it related to running rhino on my laptop?

Hello - I suspect the model is large - please export the object to a new model, with SaveSmall set in the save dilaog and send to tech@mcneel.com with a link back here in your comments.


Thanks I sent the file via wetransfer.The small size file was 160 mb.The full size file is 255mb


Hello - I think you’ll just have to wait - your object has 30,000 polysurface faces even before the meshing process. The result will likely be massive.


thanks.The export process says there are over 7 million polysurfaces.If I change the tolerance will that give me fewer polysurfaces and speed up the .stl file generation

Well it did it.It took 90 minutes for rhino to create an .stl file but it worked.And the file just about fits in the print volume of my Form2.

The stl export produced polygons - triangles - from the surfaces in the polysurface.


thanks.It seems like I often end up with very large models.Not really sure why.When I make my models I tend to make them as closed solid polysurfaces and then boolean union them together.Would it be better to make the shpaes as surfaces and then join the surfaces together?

Hello - the reason the models are so large is that, if the file you sent is typical, they are massively complex - no matter how you get there, if you make a polysurface with 30,000 faces and 80,000 edges, then it will be large on disk and make a massive mesh. All that detail, modeled, and if you are going to print it, there is no real alternnative - possibly displacement but it is hard to see how you can get the level of detail cleanly. What is the physical size of the object once printed? Is that level of detail actually reflected in the print?


the finished engine bell is 136 mm in diameter.It is being printed at 25 micron z resolution on a form2 printer so I think all of that detail will be visible.its a 20 hour print.I will send a picture of the finished print.I do a lot of spacecraft modelling and they generally have very complex surfaces.I did a motorcycle frame for a friend and that was very simple

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Here are images of the first print.the form2 is able to pritn the very fine detail ohn the model