Bed of nails prototype creation question

I’d second that suggestion of finding a CMM service.

Both of the following are assuming those 5 vias around each device are the test points you’re speaking of.

As a mildly “out of left field” alternative, Try this:

  1. Try photo-copying the PCB. That should make a reasonably undistorted image of the PCB that you can then start measuring from. (You might need to de-solder that 330uF cap in the lower right.)
  2. Pick some reference edges, (I’d recommend the top and right edges from the photo you shared, as they are straight, perpendicular, and unblemished.) and have at it with a square.
  3. Pop those dimensions into KiCAD and place the test points.
  4. Make a 1:1 test print and double check your work. Adjust the values and repeat the check.
  5. Once you’re good to go, then order a PCB for that.

Alternatively, if those vias are not filled, what you could do is use them as a template and transfer the locations to something. I’m envisioning that you use a drill (if you can find one small enough) or a dowel or needle that will fit. Ideally, maybe use a piece of ESD delrin for the substrate. You can mark it directly, and then use the marks to come back around with a mill and drill the hole for the pogo-pin sleeve. Finally, use some sort of find adjustment to set your edges.

Hope that helps.

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