Rock Shaft

On Sep 10 I made a "New Guy" post about my "C" I bought in 1989. The tractor came with a Mott 4' flail/knife finishing mower. I didn't like the way the lift was set up or how it operated. Maybe this is common. The mower was offset to the right. The drive pulley was on the left and aligned well with the PTO pulley under the seat. There was a small SA cylinder mounted on the right under or next to the seat frame. The rod end pointed to the rear. There was a wire rope/ cable with one end ran thru a hole near the end of the rod with a knot in it. On the right side of the tractor mounted to the bell housing was a pipe on a rod. The pipe was free to rotate. Three arms made of flat bar were welded to the pipe pointing almost straight down. From 2 of the bars chains went down to the mower. The third bar was near the end of the pipe and the cable from the cylinder connected to it. So when the cylinder extends it pulls on the cable that causes the pipe to turn lifting the mower. Dead simple but it didn't lift the mower level. I wanted to improve it. So I went to a used tractor parts place about 20 minutes from home and found a "rock shaft" set up. It was on the back of a junk tractor mounted to the seat frame. It had a cylinder with it. So I bought that and mounted it on my tractor with both cylinders. I had a steel plate made in the shape of a piece of pie and mounted that to one of the curved arms made on the rock shaft and connected the cable to it. (I wish I had a picture.) That worked better for lifting the mower than what I had, but not much. I also wanted to make a 3-pt hitch out of it but couldn't figure out how to mount a center link.
Anyone familiar with a rock shaft? Were they common? Was it a A-C accessory? What were they used for?
Thanks

Your rock shaft is probably the plow lift set up. I made a3 point on my C with that and the center link I built I used a piece of angle iron and mounted it under the seat and put on 2 tabs for the center link to hook to. Works pretty good. I have a finish mower hanging on the 3 point right now

My memory says the offset to the right was because the tractor rear wheel width was often wider than the mowers cut. On a "B" it wasn't an issue, but the "C" was wider.

Probably the plow/cultivator lift as Old said. I'd also agree it was offset to cover the wheel track.
AaronSEIA

Back when I built the 3 point on my C some one asked me about me using the plow/cultivator lift as part of it. Works pretty god for a home made 3 point.

So this plow or cultivator lift was a factory option?

Not an option on the tractor, but a requirement for the mounted plow or cultivator. Fairly common.
AaronSEIA

Thanks.