Both the Spindle Capper and the Chuck Capper machines pretty much share the same elements. Both have a bulk storage hopper for the caps, an un-scrambler or sorting system to orient the caps into the right side up position before placing them on the down feed ramp, an infeed conveyor that can grip the container of the bottle firmly to resist turning as the cap is screwed down and tightened onto the container, and that is where the similarity ends.
Spindle type cappers can go very fast and are more suited for containers with very forgiving low precision threads like Peanut Butter jars. The caps get pulled off the edge of the feed ramp at an angle by the top edges of the entering jars passing below on an infeed conveyor. In rows on the left and right side of the bottle a series of spindle or quill mounted reverser wheels are spinning at high speed. The wheels on the left side of the bottle mouth are spinning in a counter clockwise direction while those on the right are spining in a clockwise direction. Because the caps have a very forgiving thread pattern they sort of find their own way to the start point of the thread on the bottle mouth and then rubber tired reverser wheels mounted on the banks of spindles to the left and right side on the bottle top rotate the cap down the rest of the way. The reverser wheels don't stop when the cap gets tightened. Instead the tires start to slip because the cap cannot rotate any further. This leaves rub marks on the caps sometimes and bits of rubber start to wear off the wheels, so the tires have to be replaced from time to time.
This type of capping machine is ideally suited and very popular for applying very large diameter low profile caps onto bottles. These machines run well once they are set up and properly adjusted.