Did you know that a 5.5kg brass plate is turned into a 0.6kg sextant frame at the end of the milling process?
After milling the frames are heated in an oven, straightened, ground and engraved before the individual components are assembled.
Due to the milling process and heating the sextant frames can deform slighlty - these deformations will be straightened by gentle hammer blows.
Why do we use brass and go to all this effort?
The frame of a sextant is the most important component of a sextant. If the frame distorts or deforms, the sextant is no longer suitable for navigation due to the errors. Brass is a very robust material, and milling it from a solid piece preserves the material.
