Abstract: A support system and height control mechanism for a flexible floating cutterbar to be used on a crop harvesting machine. The support system includes counterbalancing shoe support springs that are easily adjustable to regulate the lifting pressure for the cutterbar head by the use of a conventional tool. The height control mechanism is especially useful for the header of a machine having a flexible floating cutterbar mounted on the header where a cutterbar can follow the contour of the land wherein the highest point along the cutterbar is sensed and will control the height adjustment for the header. Sensor fingers along the bar back of the cutterbar are connected through a lost motion connection to a control for adjusting the height of the cutterbar in accordance with the contour of the land being harvested.

Abstract: A cutterbar for a crop harvesting machine having narrow pitch guard prongs and knife points. The guard prongs are formed on guard sections, and the knife points are formed on knife sections, wherein the guard sections include a plurality of prongs and the knife sections include a plurality of points and symmetrically arranged mounting holes allow mounting the guard sections on a conventional bar back. The knife sections include form-beveled and serrated knife edges, together with fastener assemblies for connecting the knife sections to the knife back such as to permit easy replacement of damaged knife sections. A drive assembly for the knife bar applies reciprocating action to the knife bar. Feeder shields protect the drive assembly and enhance the feed of crop to the collecting auger.