IGES Support

Is there any way to import an IGES file?
I am under the impression that Blender does not natively support IGS, and that this is a relatively old 3D file format.
However the spine model I have is only in IGES. I’d like to try out Blender but I need a reason to do so. Right now that reason is to create some relatively simple 3D images using this spine model.

Please help. Thanks

I see. Thank you for the enlightenment.

Wow that looks great! And yes that’s the same model I’m using. Can I get my hands on that?


Sure. But first, credit where credit is due: Original model by Negar An, downloaded from GrabCAD as IGS file.

Download .blend (ZIP, 33.4 MB)
To add to your scenes, just hit Shift-F1 to append, browse to the downloaded spine.blend and select Group > Spine. No materials on the mesh.

Do not enter Edit mode on any of the meshes of the spine and do not apply the scale, as both will result in Blender spoiling the surface shading (due to Blender’s stupid habit of discarding the custom vertex normals)!

Perfect. Thank you so much!
Yeah that’s the same place I got the original as well.

Listen I will also need a pedicle screw. I was playing with this one:
Can I get that file as well?
It looks great, however I will need it scaled down about 80%. Given that this is a somewhat simpler model (with less surfacing) will we have more flexibility with this one? Do you have any other suggestions?

Does Blender allow me to establish relationships (planes, axes, etc.) in the same way that 3D modeling software does? Will I be able to tilt the “tulip head” of the screw for example?

Thanks again for your help.

Will see if I can convert that screw in the morning… It’s twenty past one o’clock in the morning here in Germany - and I need my beauty sleep…:wink:

There is nothing wrong with scaling both the spine or the screw in Blender, as long as you do that in Object mode and don’t apply the scale afterwards (applying scale = hitting Ctrl-A > Scale = making the altered scale the new “default scale” for the object). Other than that you have full flexibility for object level transforms.

Not sure what you mean by “tilting the tulip head”?

Ah, so what. It’s a simple conversion and my beauty is beyond help anyway, so here you are…:eyebrowlift:
Again for the record and to give the original creator the credit he deserves: Original model by Phill Marathakis, downloaded from GrabCAD as IGS file.

Download .blend (ZIP, 793 KB)

And again: No Edit mode, no applying of scale. Scale/rotate in Object mode as you please. The head of the screw consists of separate parts, so you could just rotate them around the 3D cursor or move the pivot point to the center of rotation.

No hurry! Thanks again.

I just mean reorienting individual components in the assembly relative to one another.

Mind the edit to my earlier post…:wink:

You’re the best.
Now to teach myself Blender…

anyone has some of the math model with parameters for the different type of curves surfaces use in IGES ?

would like to make a script to read IGES file !

happy bl

Here is the specs for IGES format. It doesn’t have math in it.

Entity 102 is composite curve, mostly describing the composite curves that form the outer boundary of a surface.
Entity 126 is B-spline curves, each B-spline curve represents a boundary of a surface, and it contains control points 3D coordinates, knots vector, weights.
Entity 128 is B-spline surfaces, basically the surfaces in IGES file. It contains all the control points 3D coords, knots vector, weights.
Entity 144 is trimmed surface, could be B-spline surface trimmed by 4 boundary B-spline curves or trimmed surface.