, is the position of the locking corner of the engaging pallet. The pallet having 12° draw when locked we place the center of the protractor on this corner and draw the angle
Q M E
.
Q M
will be the locking face of the engaging pallet. If the face of the pallet were on the line
E B
there would be no draw, and if placed to the opposite side of
E B
the tooth would repel the pallet, forming what is known as the repellant escapement.