Getting a jaw crusher to wear the ends off properly is similar to finding the proper match point on a set of cone crusher liners.

The jaw crusher was designed around an ideal closed side setting (C.S.S.). Deviation from that position diminishes the totality of jaw end wear. A hook forming on the stationary tells us that the crusher is being run at a closer C.S.S. than it was intended.

Whether that's right or wrong, it is what it is. We've altered and made special end details on many movable and stationary jaw dies, by either lengthening or shortening, to correct chronic match point issues. Length of the toggle plate and range of adjustment of the crusher affects the way the jaws align at the discharge end, as much as the way the material being crushed is reduced. If lower jaw mis-match occurs enough to affect output rate, try to correct with toggle plate and adjustment settings. If that doesn't fix things, a special length jaw can be made.