Of course, there was a difference, and still none of the
text-books make mention of it.
For the present we will go on with delineating our exit pallet. The
preliminaries are the same as with former drawings, the instructions for
which we need not repeat. Previous to drawing the exit pallet, let us
reason on the matter. The point _r_ in Fig. 23 is located at the
intersection of pitch circle _a_ and the radial line _A c_; and this
will also be the point at which the tooth _C_ will engage the locking
face of the exit pallet.
This point likewise represents the advance angle of the engaging tooth.
Now if we measure on the arc _k_ (which represents the locking faces of
both pallets) downward one and a half degrees, we establish the lock of
the pallet _E_. To get this one and a half degrees defined on the arc
_k_, we set the dividers at 5", and from _B_ as a center sweep the
short arc _i_, and from the intersection of the arc _i_ with the line
_B e_ we lay off on said arc _i_ one and a half degrees, and through the
point so established draw the line _B f_.
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