Bill, I will see if I can make a new caliper, which measures in metres, in P5 scale as Dr geep says. I'm more used to working in feet and inches, since I used to do a lot of model railway building at 4mm to the foot. That's another example of NIH, since outside of the UK everyone else adopted 3.5 mm to the foot for similar sized models. That decision, of about 50 years ago, still plagues UK model railway enthusiasts, but I digress... If I can make another caliper I will post in freestuff. Cheers Ian