Yes Ian I have one here. It measures exactly 3 1/2" in the warmth of the kitchen. It seemed to be a couple of thou down on that in the cold workshop.....Or perhaps it was my micrometer technique not up to par? Ron
It is a common problem for people who machine parts dry
So you measure he shaft in your lathe down to 0.0001" then when you go to fit it you find it is 0.001 undersize