Cessna draft control

I've heard mention of Cessna working on a draft control system for IH and others a few times on this forum. Do you have details about it and how it differed from what IH ended up using on the 06/56 series? Did Oliver end up with the system or did they only use portions of it?
I'm curious about the Cessna system because I've had the idea in the back of my head to build my own draft control system someday for fun/learning using mechanical-hydraulic parts off the shelf, and could use any tidbits to gain insight.

karl f

Marvin Darling was the project engineer and I worked with Marvin after the draft control project was done with IH. I happened to be with Marv in Charles City (Oliver) sometime in late 1965 running some instrumentation on rotary cylinders on a backhoe. At the "debriefing" meeting, after the backhoe tests were reviewed, everyone was kind of "kicking back" and shooting the breeze, someone brought up the system Marv had designed for IH in the earlier '60s (before I started working at Cessna). Marv said we still had the tractor, but no more work had been done since IH decided to use their own system, as I recall, that did not require as much re-design of the next generation tractors. Oliver asked if they could see and test the system. Cessna had a newer generation of pressure/flow comp pumps and Marv indicated if it was okay with Cessna brass, we could update the pump and show it to them. We did just that and "rumor" is Cessna allowed, or maybe sold some design features to Oliver. We set it up in Hutchinson and tested it compared to a 1650 Oliver which was demonstrated to Oliver engineers at Hutch, then sent to Charles City for further testing. The 460U came back to Cessna about a year later with the draft control partially dis-assembled. We put it back together and then swapped out the 12 for the 17gpm pump to run some tests using the 8 cu in "high torque" motor on a rotary mower. The "touch control" system was still operational in the tractor. I got along well with Marv because we both had Super 55 Oliver tractors at the time and he kind of took this young kid under his wing and taught me a lot about hydraulics.
As for the differences between the Cessna system and the next generation of IH, I may have heard some details at the time, but it's been over 45 years and I was more involved at the Oliver time, running some instrumentation and since Marv knew I was an old farm boy, got to put some hours on both the IH and Oliver in the field.

Thanks for the history lesson. And thanks for the insight into your background, as well as your contribution to the YT community. Jim

(quoted from post at 08:16:58 08/31/11) Thanks for the history lesson. And thanks for the insight into your background, as well as your contribution to the YT community. Jim

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yes, thank you, Jim said it best.

Karl F

I mentioned this in the other thread that the 12 to 17 gpm switch was the [u:cc6b8e28cc]belly pump [/u:cc6b8e28cc]that supplied the Touch Control valves. We used a 1.24 cu. in. P/F compensated pump driven off the crankshaft in front to power the draft control 3 point, in case anyone did not understand my ramblings. We mowed grass, weeds, plum thickets, or whatever with that high torque driven mower. I did a little, maybe an hour, of field testing with that too.
I worked almost 25 years in the Engineering Experimental Lab before Eaton bought Cessna Fluid Power Div., when they moved all engineering to Eden Prairie... a very sad day when the last 2 of us left the lab. I visited the eng. lab. in Minn. and they didn't have half the capabilities Cessna had.