I would recommend that these measurement be made in a standard location using a digital micrometer like the one pictured below. A standard measuring tape won't have enough accuracy.
It's nearly impossible to measure lengths of open bugles by running a tape along side of the tubing and 'guessing' with regard to what the centerline of the tube might be through various twists and turns.
However... I have a NARROW steel tape measure that I run through the INSIDE of things like leadpipes and rotor sections. It's a pretty good way to approximate the centerline measure that way. I've never tried it with a piston cluster but I suppose it could be done just as easily.
Dan Schultz
"The Village Tinker" http://www.thevillagetinker.com" target="_blank
Current 'stable'... Rudolf Meinl 5/4, Marzan (by Willson) euph, King 2341, Alphorn, and other strange stuff.
djwpe wrote:Intrigued, I took a crack at measuring my british baritone (Besson 955 3 valve comp 2nd valve bore 0.568") and my euph (Sterling Virtuoso 4valve comp 2nd valve bore 0.621").
The conventional place of measurement is the inside bore of the 2nd slide male branch. Two makers do not adhere to this convention in their advertising, Willson and Sterling. They measure the outside diameter of the 2nd slide male branch.
I have a very strong suspicion you went the Willson & Sterling way in your measurements. Otherwise your 955 would have a bore larger than the Conn 24/25I, which I would tend to doubt.
djwpe wrote:Intrigued, I took a crack at measuring my british baritone (Besson 955 3 valve comp 2nd valve bore 0.568") and my euph (Sterling Virtuoso 4valve comp 2nd valve bore 0.621").
The conventional place of measurement is the inside bore of the 2nd slide male branch. Two makers do not adhere to this convention in their advertising, Willson and Sterling. They measure the outside diameter of the 2nd slide male branch.
I have a very strong suspicion you went the Willson & Sterling way in your measurements. Otherwise your 955 would have a bore larger than the Conn 24/25I, which I would tend to doubt.
Klaus
It sure looks that way -- just checked the specs for the Besson 955 here: