We’ve seen many fingerboard extension designs over the years and we’ve borrowed from design features that work and avoid ones that don’t. Our extensions are built from a single piece of West African ebony fitted closely to the scroll, scroll cheek and nut platform. Anywhere the extension and scroll mate we go for good contact to avoid deformation when at tension. Our most current design involves attaching the extension solidly at the nut to a hidden projection of a brass E stop plate, while the other end fits freely without screws, yet precisely into the top contours of the scroll. This type of design is strong enough to resist deformation when well fitted, light in weight and easily removable. The stops and removable brass hardware for the stops are made here in house and adjustable for intonation. We typically use ebony for the capos but other material is available. (snakewood, rosewood, etc.) The stops incorporate an elastic washer underneath the screw head which takes up wood movement through seasonal changes, allowing for similar tension throughout the year.
$1400 with E stop and your choice of string. Add $200 per additional chromatic stop.