19.

Used Band Is "Short" On The Tooth Edge
"Short" on the tooth edge is a term used to describe the straightness of the band. The teeth are on the inside of the arc when the strip is lying on a flat surface.
Probable Cause :
  1. Side guides are too tight – rubbing near back edge.
  2. Worn band wheels causing uneven tension.
  3. Guide arms are spread too far apart.
  4. Excessive feeding rate.