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Full Version: Converting an STL into an OBJ

From: Bob (APTIVABOY)
17 Nov 2018   [#1]
Hi all,

I've been running into a problem for awhile now. I have a few STLs that I'd like to convert into OBJ files and open in MOI. No matter what conversion I use - various online converters, Meshmagic, etc., when I try to open the new OBJ files in MOI, all I get is a blank screen. By that I mean, I get the standard work area but there is no model being displayed, just a blank work area as if a new file had just been created for the first time. Any help? MOI seems to know that there is a file there, but it can't or won't display anything.

Thank you for any pointers,

Bob
From: Michael Gibson
17 Nov 2018   [#2] In reply to [#1]
Hi Bob, what method are you using for opening the OBJ file in MoI?

- Michael
From: Bob (APTIVABOY)
17 Nov 2018   [#3] In reply to [#2]
Hi,

I'm clicking on it. Since its the default program for OBJs, MOI opens immediately. I don't see OBJ as an option in the Import menu, so I'm not using Import.

Bob
From: Michael Gibson
17 Nov 2018   [#4] In reply to [#3]
Hi Bob, MoI should not be set as the default program for OBJ files since it doesn't open those files directly. That's also why it's not shown on the Import command.

STL files are made up of polygon data, not the kind of CAD surfaces and solids that MoI is designed to work with. So an STL file generally does not have the suitable type of data for MoI to import and work with at modeling time. You would need to open your STL or OBJ file in a polygon modeling program that is set up to work with that kind of polygon mesh model data unlike MoI.

If you have an OBJ file that has been set up for subdivision smoothing, you can use the new Subd > Create > "From file" command in the latest v4 beta but if your OBJ file originated as an STL file it is not likely to be set up as a subdivision surface model. So again it's not the type of model data that MoI works with.

- Michael
From: Bob (APTIVABOY)
17 Nov 2018   [#5]
How about an IGES or STEP file? I've tried to import them and the results have been the same.

Thanks,

Bob
From: Michael Gibson
17 Nov 2018   [#6] In reply to [#5]
Hi Bob, it's not really a matter of getting it into a particular format - the data you are starting with in STL is a faceted triangle mesh. That type of model data just isn't suitable for loading into MoI. Probably your IGES and STEP files are containing it in some special entity types for triangulated data which are not that widely supported and which won't be processed by MoI. I can verify that if you can post the files here or send them to me at moi@moi3d.com . If the files are large you may need to use a file sharing service like Dropbox or similar to store the file and then send a link to it.

It's pretty much a square peg / round hole type thing.

The data in STL files is meant to be processed by 3D printers, it's not designed to be used for transferring data for modeling.

- Michael