I want to create a library of objects, like various screws, PVC pipes and other hardware, to use as references when creating new objects in MOI. There are many thousands of .STEP files available on the McMaster-Carr web site for the hardware they sell. (See attached image)

Is there any performance or other differences between simply importing objects in the .STEP format and first converting them to .3DM before using these as reference objects to import?

Tom Meeks

Hi Tom, there is some more work that has to be done for STEP imports than for .3DM importing, especially for examining trim curves on closed surfaces.

Some CAD programs (and also STEP format) allow a trim curve to cross over the "seam" of a closed surface, which MoI does not allow and so such edges have to be found and split.

.3dm format does not allow that type of "seam crossing" trim boundaries so none of that needs to be done for .3dm import.

So in general there will likely be a performance improvement using .3dm format but it may not be very significant if the models are not very complex.

- Michael

Michael,

Thanks for getting back to me so fast! That's helpful to know.

Tom