Mechanically Up-to-Date

Sun (Auckland), Volume IV, Issue 1020, 10 July 1930, Page 8

Mechanically Up-to-Date

“GADGETS” ON THE TRAMWAYS

THE Transport Board claims that in mechanical efficiency and up-to-dateness generally its tramway system ranks second to none the world over. Reasons for the boast are given by the chief engineer to the board, Mr. F. E. de Guerrier, who cites a miscellany of improvements thought out in his draughting-rooms or adopted after appearance in technical journals. New ways of doing things are saving the board thousands annually, besides making the trams safer and more comfortable.

Driven to exponent by difficulty of obtaining materials and supplies during the rear, the engineering staff evolved methods of saving money which are employed to this day. While hostilities were in progress the old Tramway Company was hard put to it to acquire new field coils for the motors of its cars. The only thing to do was to make use of what existed and the staff invented a machine to scrape, clean, straighten. bind and insulate the old copper wire, thereby saving thousands of pounds. Without doubt a method for trebling the life of tram wheels, evolved also during the war, stands as one of the most ingenious ideas which have sprung from an Auckland engineer. It is found that wheels wear unevenly, one becoming smaller in diameter than its axle-fellow on account of irregularities in the tracks. Rotter metal or other causes. The effect is that a false flange develops on the larger wheel. Wheels had frequently to be dismounted and turned true again, with consequent loss of metal and expense, their life formerly being about 40.000 miles. Could the wheels be maintained true without taking them down? Then came the idea of fitting carborundum “inserts” into a brake shoe which was adjusted to wear down the false flange while the car was about its ordinary business. Test for the unwanted flange which forms on the middle of the tread is made by men trained to feel with the finger the incipient irregularity. The idea has caught the imagination of the \vorld-on-flanged*wheels and Mr. de Guerrier read a paper on it in Sydney. Wheels now live for 100.000 and 120,000 miles, and the saving to the board is considerable.

In earlier days the air brakes were not nearly as efficient as the latest type. When a motorman applied the emergency brake the action was delayed perceptibly, but today the system snaps on, bringing the sar to a standstill almost as fast as tie brain moves in reaction to an emergency. The braking arrangements of the latest cars are well above the requirements of the Public Works Department, the chance of a runaway now being extremely remote.

Another important innovation is the use of four nlotors instead of two for driving the cars. This idea of Mr. de

Guerrier's saves slipping, distributes the weight evenly and eliminates wear and tear. The method is superior to that employed on. most tramway systems. Manufacture of new tramcars embodies .interesting features. For the sides of the vehicles the engineers have tried all sorts of materials, semisteel, combinations of metal on wood and plain wood. All forms give a good finish,-but it is now thought that w*ood alone is most suitable and the five cars now under construction are of this material. The difficulty about steel is that repairs are costly and awkward. Cars are constantly suffering damage through being struck, or striking, other vehicles and simple wood panelling is easy to replace. The Transport Board sets a good ex ample by using New Zealand wherever possible, but wheels. axle 3, springs and electrical equipment have to be obtained abroad, mostly in Britain.

The "stop” indicators which light up for the information of motorists were invented here and work off the air-brake. The V-shaped destination signs also came out of the Transport Board's offices.

Saving of weight is an important factor in car construction. The board is experimenting with aluminium alloy instead of gunmetal and cast-iron, thk alloy being about one-third the weight of the other. Trial was made of solid wheels for the cars, but a return has been made to the spoked type, again for lightness and quietness.

All the plant used in permanentway maintenance is the last word in newness, thus the latest road rollers are run on crude oil. In the Mount Koskill workshops the machinery is kept strictly modem so that a minimum of time is needful for the repair of rolling stock.

Part of the board's policy is the removal of centre-poles, 65 being taken out during the year ended March 31, 1930. and 16 since that date. All have gone from Karangahape Road, except the one at the top of Queen Street, which makes a refuge for the man on points duty. The board is now removing poies from Beach Road and before long motorists will be able to make the journey from Queen Street via Parnell to Onehunga without seeing a centre-pole.