Hi Danny,

> I wouldn't expect changing units would effect anything in MoI's
> calculations, if a sphere is 0.06cm in MoI and I change the units
> to mm isn't the sphere still the same size ?

Well, generally algorithms work on just plain numbers...

So for example if you have a sphere that is 20 units in size (whether current units are cm, mm, miles, whatever), that could potentially give a different result than a sphere of 0.0001 units in size even if the units were set to give that some equivalent physical size.

Mostly tolerances are based at some particular fractional value, like 0.001 units regardless of what the current unit system is.

That's pretty much the regular way that CAD programs are set up. Stuff works on numeric values, and a unit system is just a separate tag to mark what those numbers are supposed to be referenced as physically.

But if you try to model a 0.06cm sphere with your units set to Miles, you will be using some really small numbers for your sphere and run into various issues, precision stuff, running close to the tolerance value, etc...


Anyway, I'm able to make this example work by just loading the file and using radius = 0.01, it should not actually be necessary to change the units or scale...

- Michael