Sorry I am new to MoI and am probably doing something stupid - but...

I have designed a small part - a bearing block in MoI (V4 Beta 0ct 27). It was created ( as part of a more complex design) by drawing a rectangle, then extruding it by 12.5mm.

The solid reports its dimensions as 12.5 x 34.43 x 45.74 (mm), the same as the rectangle and the extrusion.

If I draw a line across the face of the object perpendicular to the sides, the length of the line is reported as 25.9mm. The top to bottom measurement taken the same way reports as 40.98mm. The thickness (12.5mm) behaves as I expect.

I discovered it when attempting to round the top of the block to a 17.2mm radius - the arc extended out beyond the sides.

Am I misunderstanding something about MoI or is this a bug? I attach the model that exhibits the issue.

All is normal! Nothing stupid here!

Your object is inclined in the 3D space

The "Details" shows the BoundingBox's dimensions of a box parallel to the ground! ;)

Hi wisty, yes just to clarify, the difference is because the size report in the properties panel that shows when you select an object is the "world axis aligned" bounding box size. Since your box is tilted with respect to the world x,y,z axes that makes for the difference in measurements.

- Michael

Thanks to both of you. That is now clear - the learning curve from paper and pencil (bad) sketches to MoI is steep.

I presume that If I want a specific sized item tilted, I need to build it square to the three axes and then tilt it. Or is there another way?

Hi wisty, it can be simplest to build it along the world axes and then tilt it but it is also possible to draw it tilted directly. The Rectangle "3pts" command can be good for that:



- Michael

Thanks more for me to experiment with. I have a looooong way to go.