We spoke with flute finisher Karl Kornfeld about the tape, and he told us that it is a marker for the tenon. As you can see from the photo above, the headjoints were completely polished from top to bottom. The next step would be to lightly sand the end section below the blue tape to make a visible, "matte" style tenon that will fit inside the flute barrel.
Powell Repair Technician, Rachel Baker, shed more light on this part of the finishing process with a bit of historical and technical information. She said that flute heajoints did not always have this "matte" type of tenon. In fact, many had nothing! Several older flute headjoints, like Powell #20 in the photo below, had a ring that stopped the headjoint when it was fully in place inside the barrel. This ring also served as a position marker for tuning.
|Powell #20 is on the far right in this photo.|
Rachel said the today's tenon style serves a few purposes:
(2) It provides a smoother fit for the headjoint in the barrel. She says that there is the friction of metal against metal when you put the headjoint in the barrel, and although it may seem like a polished section would slide better, the matte area actually moves more smoothly.
(3) Aesthetics. With normal use, the headjoint tenon will get marks simply from the normal wear and tear of putting the headjoint in and taking it out. Those marks seem to look better on the "matte" surface rather than they would on a shiny one.
In the headjoint fitting process, the tenon may need to be sanded if it is too big for the barrel. However, Rachel told us that the amount used in the process of creating a visible tenon does not take off any substantial amount of material, so rest assured that headjoints are not harmed in the process of forming the visible tenon.
|Sanding lightly while headjoint is spinning rapidly.|