This is me picking up hole patterns on machinery where I have missing parts. I don't CAD much, but this is a case where teh computar machien is a very useful tool.
All my stuff is done using OSX, been using Macs since 1987. I'm guessing you could do the same thing with Windows or Linux or whatever, but you might need extra steps to rotate the scan. What's really important is that the scan comes through 1:1 in terms of scale.
Freecad is a bit of a cnut to use sometimes, but it's free and does the job.
I don't explicitly mention it in the video, but because I'm picking up a very important hole centre which has to absolutely be in the same relative place on both ends of the bed, I need a datum which is available on both ends of the bed. I did check the distances once I'd modelled both ends, I was only a couple of hundredths of a mm off, horizontally, and about 1/4 of a mm off vertically. Neat!
