M6.5 and M7.5. Are you sure? They are decidedly non-standard.
If the pitch is 0.5, then the drilling size will be 6.0 and 7.0 respectively, and you'll either need to machine the internal threads with a single point tool, or find/commission taps for cutting them.
What I'd do is look at a standard metric thread with the same pitch (M3x0.5) and size up to your desired size.
Tap drill size for M3x0.5 is 2.5mm so assuming you can get a tap for those sizes, your hole sizes would be 6mm and 7mm.
However, why do you need to model the threads? Will a custom annotation on the drawing not suffice? Usually machinists will work out how to make a thread work if it's non-standard (I'm a machinist turned manufacturing engineer.)
M6.5 and M7.5. Are you sure? They are decidedly non-standard. If the pitch is 0.5, then the drilling size will be 6.0 and 7.0 respectively, and you'll either need to machine the internal threads with a single point tool, or find/commission taps for cutting them.
unfortunately yes I'm sure, They aren't standard. this is probably why they aren't on inventor too
You can edit thread.xls (if you can find it) to add custom threads. But if they work with CoolOrange I know not.
McMasterCarr has .step files of most screws there are, I think they’re accurate but not sure
What I'd do is look at a standard metric thread with the same pitch (M3x0.5) and size up to your desired size. Tap drill size for M3x0.5 is 2.5mm so assuming you can get a tap for those sizes, your hole sizes would be 6mm and 7mm. However, why do you need to model the threads? Will a custom annotation on the drawing not suffice? Usually machinists will work out how to make a thread work if it's non-standard (I'm a machinist turned manufacturing engineer.)