Going back to the original question, I can think of four general ways in which flutes can crack. There may be others, but letâs see.
- Mechanical damage
Flute gets sat on when left lying on a chair. Flute gets trodden on on stage. Keyless flute rolls off table at session. Etc.
Simple mechanical failure, typically at tenons and sockets, but can be in the middle of tubes. Cracks normally follow grain lines, although can cut across at tenons.
- Irresistable force meets immovable object.
A flute made in a climate where there is a decent amount of moisture in the air is taken to a place where there isnât. London to India. Ireland to America. Anywhere to Arizona.
The flute shrinks. Where it is permitted to shrink, it will, safely. Where it is prevented from shrinking, it will, unsafely. Things that try to prevent it from shrinking include (in approximate order of significance) metal-lined heads and barrels, silver-lined sockets, lined key slots, post mounting, keys.
You normally get away with block-mounted keys because of their narrow profile and the airspace around them needed for free operation. Post mounting normally only gives problems at weak points like the Eb key (close to the end of the piece, with the thin socket wood and possibly complicated by C and C# key mounts). Or the G# key, again close to the end of the piece with the hole and the tenon offering only weak resistance.
The other situations all present more serious risks because the widths (diameters) are great and there is nothing to âgiveâ. These splits are normally clean and normally follow grain lines.
- Irresistable moisture gradient.
Flute hasnât been played for a week and is dry. Itâs been a long time since it was oiled. Great session, so player hammers away for 4 hours. Too many Guinnei imbibed, so forgets to swab flute out (frankly, was lucky to remember flute at all!). Inside of flute remains wet, and over the next few hours continues to soak into inside layers of wood. Wood swells and ruptures dry outside wood.
Cracks are ragged and angry looking, and cut across grain lines.
- Born cracked
Timber can come with faults, or be made faulty during the manufacturing process. Seasoning faults are a form of moisture induced fault and like them usually cut across the grain in a ragged line. Cracks caused by over stressing a part during manufacture display mechanically induced splits, usually clean and along the grain. They can be tricky because they may not show up until the flute has been played for a while.
All I can think of for now. What have I forgotten?
Terry