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Clarence, Here is a reply I made a while ago. Edited a little for your post. Let's start with the term draft which has several old meanings. One comes from the nautical usage for the depth of the water needed to float a boat. Another meaning is the amount of load when pulling. Both seem appropiate for the task of plowing where you have both a pulling load and a depth you are trying to maintain. Until Ferguson's hydraulic control design came along, maintaining a constant depth, consistant with the pulling ability of the tractor was a constant fight for the farmer. In uneven ground, varying soil conditions, the farmer had to readjust the plow as he went along, NOT an easy task. Position control allows you to set, and keep set, the height of an implement anywhere within the lift range from full up to full down. Where as draft control sets the amount of drag - or depth of a plow. Thus with draft control the implement is either full up - transport position - or full down - in working position. In the down postion, the touch control lever sets the "draft" you want for the implement you are using. If you carefully move the control lever, from full up, down very slowly, you will reach a point where the implement will slowly drop. This is the lightest, or shallowest, draft setting you can acheive. When you drive forward the hydraulic system will continually adjust itself to maintain the setting you have set. This is the genious of Fregusen's design. If you hit hard soil you do NOT have to readjust the implement height to keep from stalling or spinning the wheels. Then as you move the control lever father down you are setting the drag or draft to be harder, thus the depth or draft deeper. You can set the drag so high that the N will either stall or slip the wheels. Or at least that is true with my unweighted rear wheels. I almost always use draft control when I am grading. I find I can control the amount I am "digging in" much easier that way. You can also pickup a "set" amount of material and pull it as far as you need to. HTH Regards,
Larry
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