Measure Twice

The dimensions we need are the radii of the openings in the neck and the length of the sides of the neck. The first is fairly easy to do especially if you have a precision caliper like the one below.

neck_and_caliper

This particular caliper measures in fractions and decimal inches but I’ll be converting all the measurements to centimeters for reasons that will become clear later.

The socket end of the neck has a radius of 1.00 cm and the mouthpiece end 0.660 cm.

The inside lengths are a bit trickier. We need to measure both the top and bottom lengths of the neck. Why? Do you think they look the same length? I don’t.

The bottom length is fairly easy to measure. I sliced a thin strip of paper from the back cover of the U.S. Navy’s 36th International Saxophone Symposium schedule book. It’s a nice heavy paper that’s strong but still pliant. This strip was then fed through the neck and the excess on the socket side folded over and taped. The strip was then pulled tight out through the mouthpiece side, folded over and taped. A light shined from both ends confirmed that the strip was laying flat along the bottom side of the neck. A single edged razor was then used to guillotine the strip even with the neck openings. This strip measured 15.8 cm in length.

The paper strip wouldn’t work on the top surface though – it’s the problem of pushing rope. The paper doesn’t have enough compressive strength to lie flat along the upper surface. It always sags away. But the oil dipstick from a 2008 Mini Cooper S is flexible and strong enough in compression to do the trick. Here’s what everything looks like.

neck_inside_measurements

To get the length of the top of the neck, rest the top of the “oil full” marker on the bottom of the neck socket and hold it firmly, push the dipstick into the neck until it stops. At this point the dipstick will be laying along the curve of the neck. Without letting anything slip (three hands help here) mark where the dipstick exits the neck with a piece of blue painters tape. Withdraw the dipstick and measure the distance between the top of the marker and the blue tape . . . 17.8 cm. See they aren’t the same length.

This leaves us with a bit of a problem. Right circular cones sides are always equal. There are such things as oblique circular cones where the point of the cone isn’t directly over the center of the base but this isn’t one of them either (I can provide proof of that at another time.) And just to complicate things the neck socket isn’t conical, it’s a cylinder. That means all saxophones with a detachable neck are AT BEST a cone interrupted by a short cylinder that continues on as something that’s tapered but not conical in the normal sense.

In my book that leaves us on very thin ice. BUT we’ll make an assumption here and continue on as if everything is just fine.

Here’s (insert the voice of Frank Zappa or Don Pardo) THE ASSUMPTION: If you take the neck and carefully straighten it out, the top (outside curve) will compress and the bottom (inside curve) will stretch. The two sides will then be equal to the average of the two original lengths which is (15.8+17.8)/2 or 16.8 cm.

Next up: What’s Your Angle

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