|
LenNH
05-09-2008 07:28:53
|
|
Re: Will a Farmall H pull a 4 bottom disk plow? in reply to C-152, 05-08-2008 06:28:34
|
|
|
The early IHC sales brochures I have for H and M say that the H is a "two-plow tractor." In the "old days" (they don't seem old to me--I grew up in them), this language was a kind of code that meant two 14" plow bottoms. Another term often used was "plowing gear," which in a 3-speed tractor meant second gear. Second gear on most tractors made in the twenties and thirties is around 3 mph, give or take a little. There are a couple of good reasons for this. First, steel wheels rob a lot of the engine power (that is why a tractor rated at 20 on the belt is rated at only 10 on the drawbar). All the steel wheeled tractors I used would not pull their "rated load" in any gear higher than second. Once these tractors were converted to rubber, they became quite different. Much of the wasted horsepower could now be put to the wheels.
The second reason has to do with plow draft. According to a report published in the Journal of the Society of Automotive Engineers, February 1920, plow draft goes up dramatically with increasing speed. A "combination" bottom at 3 mph takes only 3.36 hp, while at 4 mph, it takes about 6.5 hp. We can probably assume that a steel-wheeled tractor would also be "losing" hp at the higher speed because of the increased rolling resistance required to drive the lugs into the ground. If your tractor is rated at 10 or 12 drawbar horsepower, then it will easily pull 2 plow bottoms at 3 mph, but will not pull the same 2 bottoms at 4+ mph. I used two Hs extensively for 15 to 20 years. The first was a distillate model, the second a gas type. In the heavy, somewhat clayey soil of central NJ, neither tractor would pull 2 12" plows in anything but second gear (about 3.5 mph). VERY occasionally, in the lightest soils (like last year's wheat field which might have been disked over in the fall), you could get these tractors to pull in third, but they always felt like they were at the limit. These tractors may have the hp of their predecessor (F-20), but their engines are much smaller and do not have a lot of torque. You could overload the older tractors, and because of their big, torquey engines, they would keep slogging through. An H would just die out if you overloaded it. I am looking at the IHC brochure right now, and it shows a 2-furrow HM-150 disk plow on an H, and a 3-furrow HM-150 disk plow on the M. Widths of the plows are not given. Incidentally, the 3-bottom plow could be reduced to 2 furrows if conditions got tough. Curiously enough, later on in the brochure, there is a picture under "Trail-Behind Machines" showing an H with a 3-furrow No. 34 disk plow at work on a tobacco farm in Lancaster Co., Pennsylvania. The soil looks pretty friable, so maybe that explains how the tractor can handle the extra disk. No size given, so it is hard to compare this plow with the HM-150 directly-attached plow. I am pretty sure that the plows we used to use back in the 30s, 40s and 50s were designed for work at about 3 mph. I wonder if the plows that are used today have different curvatures to the moldboard, and maybe slicker surfaces, so that the tractor can move faster and not have so much resistance to overcome. Fellows farming today with the modern machines, can you comment on this? Always did like comparing tractors when I was actually using them on the farm. I hope all this gobbledy-gook makes some sense.
|
|
|
