plunger 102 in well 110 stitch length control lever 86 is pivoted at one end under a spring 121 on the shoulder 122 of a screw 124 which is affixed in a platform 125 the opposite end of the lever 86 carries a knob 126 for use in moving the control lever about its pivotal axis which is perpendicular to the pivotal axis of lever 78 to position camming surface 98 along the length of an engaging curvilinear undersurface 128 of spring biased lever 78 by pivotally moving control lever 86 an operator can select a position for lever 78 and thereby control the operation of the feed regulating mechanism to determine stitch length the length of the stitch length control lever between its pivotal axis and camming surface 98 is of a length which is sufficient to prevent disengagement of surfaces 98 and 128 throughout control movements of lever 86 vibrational forces are imparted to lever 78 by the feed regulating mechanism during operation of the machine and cause the lever to impact against camming surface 98 on plunger 102 however undue noise resulting from such impacts is prevented both by operation of the plunger and by the sound deadening nature of the materials used in the plunger o ring assembly the plunger is of.