Distance command, Cen and Perp osnaps…
Hmm - are those actually round holes or is this a mesh thing?
Yes, I’m having trouble getting a measure from the center of the holes
‘Yes’ it is a mesh? In that case, DupEdge the long edge. Do something like set a point with Between and Vertex osnap to mark the center of the hole (or just do it directly with Between without the point) . Uae Perp on the second point on the duped edge, now a line.
Pascal’s method will work.
Personally, I recommend some caution with the Distance command. It is very easy to get undesired results (for reasons described below).
You might find that it is far better to draw a line and check the object properties of the line once you’ve verified it is accurately placed – especially when specific points are not involved, as is your case. You can also use Dist on the new line with just End Snap and be confident of the result.
Use of the Distance command is not as simple as one might imagine (or should be) – and a fairly thorough mastery of snaps and ortho behavior is required for complete confidence in the results. In Rhino, Snaps over-ride Ortho behavior (for reasons I fail to see any benefit in because this is a seriously terrible idea) and the use of Dist leaves no “trace” of what exactly was measured. Meaning: one can easily get a repeatable distance measurement that is not the desired distance, simply because one’s settings were not sufficiently considered, accurately predicted, or well-understood.
Drawing a line, on the other hand, leaves a visual object that you can then verify (in multiple views), measure, and later delete.
I agree. I’ve done that a few times with distance measurements that at first look like they are straight but are actually snapped to something else and your measurement is completely off without realizing it until you’re too far along to undo. I make it a habit to always draw construction lines, verify they are positioned exactly where I want them, then analyze length. That’ll never fail you