Arizona republican., 1918-10-13

even for light car construction. The friction set has the great advantage of being cheap to make, and from the drivers point of view it has the virtue of giving theoretically limitless num- Der of speeds.
 The planetary gearset is also cheap form of construction and consists of group of spur gears always in mesh with master of sun gear. This forms a rough likeness to the solar system, with the sun in the center and the planets revolving around it. hence the name. In action the gears are forced to revolve on each other. This is ac- complished by stopping the movement of the parts supporting the gears, which is done by means of a sort of brake. When the gearset is in high it revolves as a unit, which gives a re- markedly efficient action. While it is possible to construct planetary gear set for any number of speeds, in prac- tical application two speeds are all that are used. To increase the number means increased complication and de- stroys one of the great values of the type, simplicity and cheapness to build.
 The very crudity of the conventional sliding selective gearset, with it's parallel shafts and gears slipping into and out of mesh while the shafts are revolving at high speed, ought to sug- gest to the car owner certain obvious facts. These facts are the need for reasonable handling in operation and careful maintenance of such a much abused piece of mechanism. If the gearset is to run without growing and claShing of gears the shafts must be perfectly parallel so that the gears will mesh accurately. When the shafts get out of alignment, whether it is be- cause of wear in the bearings or springing of the shafts themselves, there will be clashing of the gears un- til the teeth have clipped, the gears have broken or something else has | happened to make repairs imperative. It frequently happens that the rear crankshaft bearing may not be an ac- curate fit and this throws out one of the transmission gears and causes a | binding. When once miSalignment oc- CUTS in the transmission there is no | help short of replacement of the part or re- establishment of proper align ment if the parts are uninjured. It often happens that a car owned may replace gears that have become noisy only to find the new set just as bad. This is because the shafts are out of line and no gears will perform prop erly until the condition has been cor rected.
 The one thing that enables the gear set to perform it's onerous duties and stay on the job is plentiful and correct fabrication. Oil is the proper lubricant for the transmission. nov grease, as used to be thought the case, It is well to use a heavy oil in summer aS. a thinned oil during the cold weather. At least three times a season, or bettel still every 1000 miles of running, the transmission case should be drained. flushed out with kerosene, and then re- filled with fresh oil. In this period when it is difficult to ret new cars and replacements of parts are slow and un- certain we cannot be too earnest in ad- vising our readers to give the most | scrupulous attention to the fabrication | of hte gearSet. Neglect here will bear rapid fruit, while systematic care of the gearset will probably keep it going during the difficult period of the war
 As to the future of the transmission | it is hard to say what will happen Bad as present types are. there is nOth- ing in sight to take their places. The magnetic gearset has great advantages but they are gained at the expense O. added complications, greater weight and very much greater cost in con
 struction. The beautifully simple fric'
 tion set gives no promise of coming
 back in a more satisfactory form. On'
 ray of light has appeared on the hori
 zon in the shape of an hydraulic trans
 mission, and while this is still il
 embryo, there is a possibility that i
 may be the prevailing type of the flu
 ture. At any rate our engineers ar'
 certainly not going to let the presen crude gearset remain "in power" yer, long after they get down to work agaiI when the Hohenzolern devil has beer exercised for all time.