I have never heard of the term SLIDING CALIPER I think the correct term might be Veneer Caliper, not to be rude either but if you are going to correct someone you should use the correct term! Mine are STARRETT. As for the Shaft measurement it is from the top of ferrule where the tip is applied not the wood below the ferrule ,this type of measurement would have you listing the shaft 1" to 1 1/4" shorter than it actually is! Just sayin....
Not to be rude but "now you have"! I used the term slide because the original poster did. And it is Vernier , not Veneer. Most people today use LED Digital calipers but there is also Dial Calipers but they are all sliding. And starrett is just a brand not a type.
As far as measuring dia. (not lenght) correct position is just under ferrule as stated. I was not talking about length of shaft!
I guess I should have known better than to comment from the start.
Vernier Slide Calipers
Vernier Slide Calipers Are Ideal For Construction And Machine Shop Measuring Applications.
Vernier Slide Calipers are made of heavy duty materials for long lasting durability. Vernier Slide Calipers are available in a variety of types and sizes with assorted features.