After the axle has been assembled, it is inspected and passed to the testing department. In the testing department, wheels are applied and the axle mounted on a stand for testing. The axle is driven by an electric motor, brakes being applied to provide the equivalent of a load. The tester then notes the noise of the axle, and the contact surfaces of the teeth, and if final adjustments are necessary they are made in this department. The men are rear-axle experts, and understand thoroughly all the adjustments of the rear axle. They must be able to handle the axles and lifting is often times necessary.
The axle after being tested is numbered, tagged, and sent to the storeroom for shipment. In the rear-axle factory, there are many classes of workers which have not been mentioned. Some of these are draftsmen, tool-room helpers, storekeepers, clerks, checkers, timekeepers, janitors, gate keepers, machine hands, truckmen, and mechanics. Much of the work done by these men could be done by men handicapped by loss of hand, leg, eye, or hearing. All of the work pays a good living wage, and working conditions are good.
PLAN No. 1127. UNIVERSAL JOINTS
Unit manufacturing has been specialized to such an extent that there are now factories which manufacture nothing but universal joints. These are small but very important units. In the universal joint factories we find steel presses, drop-forge machines, machine-shop equipment, and assembly departments. The work as carried on in these plants has been fairly explained in other parts of this monograph.
PLAN No. 1128. TRANSMISSIONS
Transmissions are another unit of the automobile that are sometimes made in a specialized plant. There are several well-known transmission firms who make nothing else but transmissions and gears.
The transmission case is usually made of aluminum and is cast into the proper shape. In the foundry are found the same classes of workers as in the axle factory, only the men are casting aluminum instead of steel.
The case having been cast is dumped from the sand, cleaned, trimmed, and inspected. Any small holes are welded shut, and the case is then cleaned ready for the sand blast.
In sand blasting a stream of air and sand is played against the part. The air is under high pressure and the sand fed in plays upon the aluminum at a high velocity, cleaning and smoothing it. Operators of the sand-blast machine wear masks and dust-proof suits and work in a special cabinet. It is impossible to work without this protection.
After being inspected the transmission case is passed to the machine department, where it is machined to receive the bearings, covers, etc.