This article originally appeared in Farm Implement News, May 15, 1930. It was sent to us by Dwight Rhodes, R #2, Clifton, Kansas 66937.
Not so long ago, the following prophecy appeared in these pages: 'One thing is sure; progress in general purpose tractor design will come with the development of diverse but successful types, rather than assuming that the overall design of the first machine is the only design that can prove successful.'
One man can couple the tractor to the take-off operated tool.
This statement was made with full appreciation of the remarkable job that Bert Benjamin did when the Farmall was developed.
Now comes considerable fulfillment of this prophecy in the form of the Massey-Harris general purpose tractor. It is the first really engineered four-wheel drive job that the writer has ever seen.
The designers of this tractor had the following requirements in mind: It should be able to operate satisfactorily on any soil or slope where a four or six horse team can work.
It should be adaptable not only to specialized tractor tools but also to the horse tools that the farmer already possesses.
It should be light enough to be worked on plowed fields, the soil of which may not be helped by packing, but have enough traction to meet every demand of two-plow service.
Offhand, one might remark that these requirements make a rather large order. But look at the Massey-Harris solution of the problem.
They made the general purpose machine a four-wheel drive. Yet they kept the advantages of three-point suspension without even the restrictive effect of springs between the oscillating axle and the frame. The rear axle can rotate around the longitudinal center line of the tractor, and wherever the lugs of either wheel are 'touching bottom,' they are yanking away at dirt.
For quick response to steering, it was felt that the front wheels, notwithstanding they also are drivers, should pivot just like any standard steering wheels, and they do. The driving torque goes through universals on the principle of those on a Cord front drive.
Then to get all the theoretical advantages possible in four-wheel drive construction, it was necessary to change radically the normal ratio of weight on front and rear wheels. With rear wheel drive machines, the static weight on the rear wheels will be approximately 60 percent of the total, with 40 percent in front. This static balance changes the minute the tractor begins pulling so that weight in effect is transferred from the front wheels to the rear. This is particularly noticeable in the case of a light tractor pulling its maximum load, for so little weight may be left on the front wheels that it may be difficult to keep the front end going straight, except straight up.
With the Massey-Harris general purpose, the statement is made that every ounce of its weight 'is balanced over its four wheels when a normal load is pulled.' From this it can be assumed that with the tractor idle, the greater proportion of weight is in front, but when pulling, the torque reaction of the lugs against the ground transfers enough weight to the rear end to produce almost equal weight and lug grip to each of the four wheels when they are pulling their maximum. This, it might be remarked, is the only way to get the utmost possible advantage out of four-wheel-drive design.
All this translates itself into positive traction, usable not only when surfaces are good and when the lugs can bite, but also in powdery peat and mucilaginous mud. And in row-crop farming, there are plenty of peat beds to be plowed and fitted and plenty of low spots that it is unhandy to swing around when the rest of the field is in perfect condition for cultivation and the weeds and grass are growing between the rows.
In adapting the general purpose to every variety of horse or tractor tools, the designers approached the problem from two angles.
First they worked out very easy controls, so arranged that extensions to pulled equipment could be easily and quickly made and when so made, the outfit would be just as responsive as a well-trained team of mules, if not more so.
The other factor is ease and quickness of coupling the tractor to a drawn machine. Sometimes when such a hitch is to be made, the hired man is mending fence at the end of a 160-rod field. To call him back to help couple the tractor means no fence fixed. But with this Massey-Harris, one man can stand back of the tractor, lift the drawbar of the implement, and with the other hand on the clutch lever, edge the tractor back by inches so that hitching consists of dropping in the pin when the holes mesh. One man can even connect a tool with power take-off connection. Hitching the general purpose to a regular two-row cultivator would be much quicker than getting out three or four horses and hitching up.
How the Massey-Harris designers combined a strong two-plow tractor engine, a frame, and a transmission train to four wheels, and still keep the weight down to 3810 lbs. (which is what the general purpose weighs) is something they probably will have to explain when their friends in other companies get them in a corner at the next A.S.A.E. convention.
The engine is a four-cylinder 4x4?', L-head, governed at 1200 r.p.m., developing a maximum of around 25 HP, according to the company. Our guess would be 26 to 26? HP if test conditions are favorable and the engine happens to be a high tester. There's always some variation between engines of identical design. At the drawbar, the general purpose ought to develop 17? HP, but she might run up even as high as 20 if track conditions are favorable.
The transmission provides three speeds forward: 2.2, 3.2 and 4 mph, with reverse 2?. Two brakes are provided, one for each front wheel mounted on the differential shaft. These will act as stall preventers if one wheel should land in a mud hole with a soup bottom. Clearance between axles and ground is 30 inches, wheelbase 51 inches, and tread 76 inches. The inside turning radius without brakes is 6? ft., with brakes 3 ft., sort of pirouetting on the inner hind wheel.
The belt pulley, which is detachable, has a 12-inch diameter and 6? inch face and turns 800 r.p.m. The power take-off is 545 r.p.m., and ends in a standard 13/8 spline connection, with 11/8 spline furnished on special order.
The extension controls to the seat of the drawn implement are furnished as extra equipment, as are electric lights with generator and battery, and electric starter.
The most appealing thing about this Massey-Harris general purpose is not its beauty and cleanness of design, but its reflection of the forward-looking mental attitude of the men who set their O.K. on its production, and those men must be Thomas Bradshaw at Toronto and Grover Weyland at Racine. It takes nerve to depart from the blazed path of easy progress and to strike a new trail even though one is confident that it will lead to a great goal beyond.
This Massey-Harris G.P. offers proof that in the farm equipment trade, competent designers dare do what they think is best, and having done that best, find their work appreciated by management. No industry will stand still, let alone retrograde, with that viewpoint.