Fred the Red Shirt wrote:

If you have to scale something for yourself off a drawing (or within
a cad model) then my advice is to be cautious and plan for a little
hand-fitting to make it right.


I was referring more to crosscheck measurements. You ever measure
something, maybe even two or three time, and just 'see' the measurement
you expect instead of what's actually there? With CAD, you can drop a
couple of extra measuments. Seeing a second measurement wrong is more
difficult. You have to be trying to screw up the third one. I like to
pull any important measurements from three points when I can. If
they're not all in agreement then I stop to figure out what's wrong.

--
http://www.ernest.isa-geek.org/
"Ignorance is mankinds normal state,
alleviated by information and experience."
Veeduber