Import STL and use in millimetres

[Anonymous]

Hi All ! I have recently been converting some STL files into IPT files (with the guidance of members of this forum, using Mesh Enabler). I want to work with the files in 'mm', however, they are in 'inches' by default I think. I have asked someone how to convert into 'mm' and they have given me the advice to select the mm option when importing (please see attached image that they sent me - they do not seem to be using Autodesk inventor). Looking around on Inventor I cannot find the option of importing it and changing to mm's....is there a way of doing this? Any help on this would be greatly appreciated. I simply converted to base feature and then saved the result as a solid IPT.

[Anonymous]

p.s. not sure why the forum is not allowing me to attach the picture.

[KevinLi-Autodesk · Accepted solution]

Hi Rashpal,

Thanks for reporting!

Please refer to attached image.

Regards,

[Anonymous]

Hi Kevin, Thank you for the image. How do I get to this option? Also, should I select this option before I convert to base feature or after?

[JDMather · Accepted solution]

You select the Options before even opening the file.

Select the file to open, and then BEFORE OPENING, select Options.

There is a chance your part will still be the wrong size, so check.

Do you know how to scale or change document units?

[Anonymous]

JDMather, That works fine. Thank you for that. & thank you to Kevin also.

[pcrawley]

I accidentally found another way to bring STL into Inventor that gives remarkably good results without using Mesh Enabler - so I'm sharing 🙂

If you import the STL into 3ds max you have a number of tools to fix-up the mesh ("STL check" and "Cap holes" are good modifiers to try).  However, if you  are not a max user, you can just export the model as a .SAT file and open that in Inventor.  Watertight meshes (no holes) become solid parts in Inventor - and meshes that weren't watertight become composites.

The only reason I mention this process is because (in my recent experience) STL meshes are often either very coarse (large facets) or very fine (tiny facets) and max has so many tools for dealing with these extremes.  If you've ever taken a large STL file into Inventor, the face count can be horrific and the model size unworkable.  The tools in max give you a good chance to refine the mesh to a sensible size before bringing it into Inventor.

[KevinLi-Autodesk]

Hi rashpal,

It's my pleasure! If you meet any other data translation issues please post in this forum or just contact me via Hongyuan.Li@autodesk.com , my team will take a look.

BIG thanks to JD !

Regards,

[Anonymous]

Hi PCrawley, That was very useful information. Thanks for that. Not being a 3DS MAX user myself I exported the STL as a .SAT file and then imported into Inventor. I get a message saying "No Bodies Read From File"....so I am guessing this method may not work? Kevin, Thank you for the kind offer of help. Much appreciated.

[KevinLi-Autodesk]

Hi Rashpal,

STL format is a pure mesh data, when open it in Inventor and export it to .sat, nothing will be exported since Inventor does not support to export mesh data to .sat, if you open .sat file with Notepad++ you will see only the file header is generated but don't have detail data of geometry. So when open the exported .sat back to Inventor, nothing will be imported and translation report will prompt "No bodies read from file".

In 3DS Max I suppose it has some mesh tools or features to convert mesh data to brep (just like mesh enabler tool), need to convert mesh in 3DS Max first then exported to .sat, and also the exported .sat which contains brep information can be imported to Inventor,

Regards,

[Anonymous]

Hi Kevin, Aah, makes sense now! Thank you for that!

[pcrawley]

Hi rashpal

It does work - honest!  In max, import the STL file.  Even if you don't know max at all, just export the model using .SAT format.  After entering the file name you get another dialog with 4 options - tick "Export Mesh Objects (Objects collapsible to Mesh)"

When you go to Inventor and try importing the model, select the .SAT file name - then hit "Options" and make sure "Solids", "Surfaces" and "Wires" are ticked.

Any problems, post (or private message) the STL file you are trying and I'll see if there's something "odd" about it that causes the above to fail.

(Attached is the classic 3ds max teapot with the handle, spout and lid pulled off - exported as a SAT.  You can bring this into Inventor with ease as a composite surface model, but not as a solid because the mesh is not watertight.)

[Anonymous]

pcrawley, Thank you for the detailed guidance! I will have to try that very soon. Will doing this also save it with less 'triangles', so it is more of a solid and essentially easier to work with?

[pcrawley]

With some unexpected free time this evening, I put this video together showing the max > Inventor workflow:

http://www.screencast.com/t/QQVxX0v45HxY

If you just want the import workflow, that's the first bit of the video.

The second bit of the video is reducing the polygon count.  There are several ways to do it, but I figured 2 clicks in max was pretty easy to follow!

The last part of the video show how you could fix holes in your STL meshes - this way you stand a better chance of getting a solid body in Inventor.

Hope it helps.

[Anonymous]

Pcrawley,

Wow! that is impressive! That was a really useful video. I hope you can leave it on the link for future reference?

Once again, Thank you for that.

[Chad-Smith]

I've been trying to use millimeters too, but the Options are greyed out. Even though I have the file selected.

[KevinLi-Autodesk]

Hi Brausmith,

Do you use Manage tab -> Insert -> Import to insert the STL file ? if this is the case, then the options will be grayed out since it is insert import. The options are available for Open.

Regards,

[Chad-Smith]

Thank you. That did it.

[Anonymous]

Thank you, this post helped me solve the same issue!

cheers,