1934-08-07 — Page 2

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ANTI-DAZZLE FOR OLD

CARS

How Dimming Equipment Can Be Improvised

Soon after electric lighting for automobiles came into vogue it became evident that if one ar- ranged to have an efficient light for moderate speed driving some method of cutting down the glare or dazzle effect was required when meeting oncoming traffic.

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It is not surprising then that ail kinds of arrangements have from time to time been suggested as a compromise. but so far the ideal method seems to me not to have been hit upon for application to an existing and perhaps old car.

Fortunately there are some mo- derately successful methods, easy to incorporate and simple to work, and until the Ideal arrangement does materialise, we shall "un- doubtedly have to get along with these. The arrangements men- tioned may roughly be divided in- to two classes. Those making the change by mechanical means, in- cluding electro-magnetic devices; those controlling the amount of current passing through the bulb flaments.

Mechanical or Electrical

IN

The first includes all manner of mechanical devices arranged for, dipping and swivelling, together with such things as movable houds and ieflectors, whether operated by purely mechanical· means, as by levers, rods, and Bawden wire, or by electro-mec- hanical means such as magriels and solenoids. The second class is self evident and includes switch- ing out one or both head lamps,:: incorporating two-Lament bulbs, or separate bulbs, and dimming one or both lamps. by means of inserting a resistance in the clr- cult. The first class contains some very commendable arrange- ments, simple in construction and fairly easy to work, but Atting these to existing cars is not such a simple matter.

For those, then who run ser- viceable cars with no such attach- ment already incorporated, it is Interesting to recount some ex- periments carried› out to investâ- gate the problem along the lat- ter lines, with some constructive details of suitable conversion. As the essential feature of any ar- rangement is that it shall be "easily fitted or incorporated; the method of utilising two bulbs, or bulbs containing two flaments, was ruled out, as th's involves switching arrangements easy en- ough to incorporate in a car when built, but not so easily fitteď later..

First of all it was desired to in- vestgate what could be done by means of producing various beams by careful focusing and arranging them in such directions that they did not interfere with oncoming traffic. This method it was soon found, had to be aban- doned, as if the beams were set far enough to the left to avold dazzle it was very awkward to "steer info a gateway or mund a right-hand bend, and If, on the other hand, they were dipped on to the road sufficiently to avoid- dazzle, the angle had to be so se- vere that it seriously interfered with driving at any reasonable speed. These results are what might be expected, but they are mentioned as they definitely indi- cate that if dipping or deflecting to the left is favoured it requires to be properly done by one of the many excellent arrangements now. on the market."

Leaving the off-aide lamp in the orthodox position and deflecting the near-side one towards the kerb, with provision for switching out the former, proved fairly sat- "Isfactory to, oncoming traffic but not so good from the point of view of providing an emcient driving light, as almost 50 per cënt, of the light was wasted; moreover, efforts at effecting a compromise varying the angle of the kerb light were of little avall as they again either produc- ed dazzle or wasted the light.

This left the well-known idea of incorporating a resistance or dimmer in the circuit, and as this. method proved very satisfactory, except for some, little inconven ience in operation, attempts were made to overcome the dificulties. Now, in studying the action of a dmmer it is necessary first to consider the amount of light emitted from the bulb in relation to the pressure applied or the current passing. The light emit- fed bears very little relation to the wattage absorbed by the s ment; for as the voltage and cur--

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rent begin to rise, the emission starta at the red end of the spect- rum and proceeds towards the violet end at an increasing rate. So far as effectual driving illu- mination is concerned, the red or long waves are of little account except for misty or foggy weather, the shorter or violet waves be-. ing the ones giving the desired effect normally.

The rate of production of these rays, as the voltage and current increase indicates the rise in candle-power from zero to a ma- ximum At half the rated voltage" only a red "glow was discernible, and it was not until the pressure had risen to 75 per cent of the rated voltage that any useful light became evident.

Drawbacks of a Resistance In other words, this curve ex- plains why it is that the usual dimm ng resistance is not too easy to manipulate, this being due to the rate of resistance increase or decrease bearing no straight line relationship to the light F duced. Operat ng these devices was found to be rather a jerky business, the tendency continually being to dim more than necessary or not enough. The trouble can be partially, surmounted by grad- ing the resistance, but this does not remove the difficulty exper- ienced on rough roads, and, more- over, pushing and pulling a knob is not the most convenient form of operation.

A switch was obviously the bet- ter arrangement. This consisted of a resistance short-circuited by a switch, and an idea of the value of the resistance required may be ascertained from the following

Speaking in terms of amperage Instead of voltage, and taking, a specific case, it was found that the current passed by the head.. lamps on a typical 8-volt installa- tion amounted to 8.6 amperes for. both head lamps. On cutting this down in stages it was found that the minimum useful driving light was reached when the current fell to 5 amperes, which is a re- duction of 1.6 amps, or 24 per cent.

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In other words, the total cir- cuit resistance, neglecting the leads, with the lamps full on was 0.809 ohms, and similarly the to- tal resistance when dimmed was 1.2 ohms, or an increase of 291 ohms. Clearly, then, a resistance " of, say, 3 ohms arranged to be " short-circuited by a switch was a convenient arrangement, and so it proved to be, for with the switch in a handy position it could be flicked on or of without the slightest trouble, a fixed dim- inution of Ight taking place which precluded any human error interfering with safe driving llu- mination.

A

As voltages and lamp consump- tions vary on almost all cars, the resistance required in the follow- Ing manner. Taking the case of a 12-volt installation, the current passed by the head lamp bulbs can be gauged from the reading on the ammeter when the bead lights only are switched on. As- suining bulbs are Atted consum- ing. 4 amps, or 8 amps in all, the total circuit resistance is 1:5 ohms. This current must, as previously shown be reduced by about 24 per cent. or. say, by a quarter to.

HONG KONG DAILY PRESS, TUESDAY, AUGUST 7, 1934.

MOTOR SUPPLEMENT

"AUTOCAR" ROAD TESTS USEFUL RUBBER

The Ford V8 Saloon

De Luxe

In the two years it has been ́avaliable in England the Ford VB has had a very successful career, for it has become widely known not only to owners of the car as a machine" with a pheno- menally good performance, whilst in trials, too, It has done remark- ably well almost without excep- tion.

It is interesting considering the 1934 model, which has even more engine power, due to the use of a dual-type carburetter, changes in

the inlet manifolding and other points, besides detall re- finements in the body, to reflect that the V8 when, it first appeared was the forerunner, as far as this country was concerned, of a new type of car of American de- sign with an extraordinary per- formance by reason of an unus- ually high ratio of power to the weight of the complete Cor There are few cars, except others from the same country as far as design goes, which can hold or surpass this V8 in acceleration up to about 60 m.p.h., and such snap in the getaway is a most voluable feature on present-day roads.

It is a car which, as well be seen, has a high ultimate maxi- mum, for, apart from the timed speed given, which, as usual, is an average of several runs in op- posed directions, Fun with the wind gave 81.82 m.p.h. against the stopwatch but it is not as an 80-mile-an-hour car

that

the machine principally calls for the high praise it is its vived acceleration up to ordina- rily usable speeds on roads as they are nowadays which impres- ɛes, and which is so well worth having.

Good Pick-up

the

The figures in the table for acceleration over

various rangs of speed, and through the gears up to 50 and 60 m.p.h, are. more than usually worthy of ex- amination. It is seen also that besides getting away with an al- together remarkable

rapidity

from the lower speeds, the acce- leration la maintained with very Kttle falling off indeed in the middle range of

speed: which counts for so much on the road. Not only has the V8 such a per- formsnce on the gears that the ordinary kind of sports car can comfortably be left. but on top gear, too, the ability to pick-up in astonishingly good.

It has to be remembered in this connection that the model: tested is the four-door saloon de luxe, which is a bigger and hea- ver body compared with the other and more generally seen models on this chassis.

As a whole, the figures are one of the very best sets that have been recorded in these tests, though that is a thing which has had to be said more than once. during the past twelve months.

On the gears the maxima are as high as 35 mph on first, and a genuine 60 on second. The spee- dometer proved to

!!

and very smoothly, with almost complete, silence and very smoo- thly, with almost a floating- sen- sation, up to about 60 m.p.h.. round about which is a very happy.cruising speed, and much beyond that noise-chiefly from the carburetter intake. It seems --begins to increase to some ex- tept. 1

It leastonishing how quickly. speed is gained up to the 65's and 70's, and on the whole there is

little more apparent mechanical

TUBING

Treated With Adhesive Solution

Overlapping Tubing is the name given by the Leicester Rubber Co., Ltd., of Evington Valley Mills, Leicester, to one of the latest of their John Bull products. The new tubing takes the form of a loose roll of rubber, the edges of which taper to a point. Varying widths 'can be obtained according to requirements, and it is suppiled to whatever length is wanted. The surface of the rubber is treated

effort at 70 than lower down the scale. "As a matter of interest,

with an adhesive solution, so that it can be wrapped round an ob- an acceleration figure was taken through the gears from rest to a

ject and attached in position by genuine 70 m.p.h., two runs in moistening the solution with pet

rol, the opposite directions giving remarkably fine mean of 26′, seconds.

Undoubtedly, compared with earlier examples of the model, performance has been improved materially equally," the handling · of the car, which is so very im- pertant with one of these cap- abilities. The steering feels more accurate and safer, it is very rea- sonably light without being in- definite, and, perhaps most im- portant of all, the stability of the car at speed. and especially on corners, is a great advance, the shock absorbers presumably hay- ing been made to do more work. yet the springing is not hard.

Brakes Excellent

OW

The brakes, too, seem to give more power. They are of a kind.. that require firm pressure to pro- duce the maximum effect, but quite light pressure on the pedal affords the sowing down normally brakes required, and they are which can be applied without set- ting up complications.

used for top and second gears, A synchronising mechanism is

and this works very well for or- dinarily fast changing or for more deliberate methods, with a single clutch movement alone. Second gear is notably quiet and hardly distinguishable from top, and the lever is long and very well placed. The clutch takes, up the drive smoothly. On top gear the engine. will pull down to about 5 m.p.h... without "anatch, but at lower speeds. there is always an induce- ment to engage second for sake of the extra acceleration so rea- dily avaliable.

This four-door saloon has mo- hair upholstery, and a singlepiece front seat which can be imme- diately adjusted to give a quite comfortable driving position. The back seat is wide enough for three passengers. Built into the driving mirror is a small neat .clock, the dial of which is titimi-

nated at night. - .

The head Lamps give a fairly good but not superlative beam," though it must be mentioned that the car in question had seen some thousands of miles of service, and Rally back in March. in fact, took part in the R.A.C.

There Is a

neat and practical system of ventilation, the win- read slow-dows in the forward doors being

right up to 70, and did not ex- ceed a reading of 81" during the fastest timed runs mentioned.

when

6 amperes to produce the neces-- A great feature in handling the zary result, the total circuit re- sistance to effect this being 2 ohms, scheme of putting the head lamps in series by means of s series parallel switch might be effective and also more econo- mical, but besides some complica tion in the wiring this results in top great a light reduction, which, will be understood by considering a similar case.

From the previous example. when bright or fill ou, the volat current is 8 amps and the circuit resistance 1.5 ohms. Neglecting the leads again, each bulb then represents 3ohma, because in parallel the resistance is 1.5 ohms: The current passed with both bulbs in series is 2 amps, repre- senting a reduction of 75 per cent

The particular method of dim- ming described proved very saz- isfactory considering the present state of the development of the art, and where it is not bought worth while to it more elaborate arrangements it will be found well worth incorporating, as the lamps may be fixed in the normal post- tion to suit individual taste, arid:

car on the road is that, quite apart from the way in which it Literally leaps forward given, full throttle, on the lower gears, with a feeling of unboun- ded power, it answers instantly on top gear as well, treats as use- ful and safe sections of road for awift acceleration, and, in fact has so much power that the per- formance is of a kind to be used with discretion on any road that is at all busy.

Remarkable Results

It achieves these remarkable/ results in almost complete allence

the Atcking of the switch on or off interferes but negligibly with the driving

The resistance, after winding, may be axed upon any convenient part, such as the back of the dash, this being easily arranged. The first one used was of a fixed type, but it was later found an advantage to use a few extra turns of wire to that the clip could be moved, along to vary slightly the amount of

so arranged that movement of the handle beyond the fully closed position slides back the glass an inch or so, leaving an extractor gap. The engine is compact and, in particular, has the sparking -plugs placed very accessibly

indeed.

One buys, at very moderate outlay, a terrine performance Ford Va. The price, incidentally, and a go-anywhere, car in this has been materially reduced re-

cently.

EASILY-MADE HAT HACK

A satisfactory hat rack can be made in the roof of a saloon with four small screwed eyelets usually eight for a penny-and a piece of coloured cord to tone with the root lining. Two of the eyelets are screwed into a wooden cross- piece in the roof, about 7m apart, and the other two in a corres ponding position on the next cross-place. The cord is motted at one end, then threaded through the other three eyelets and knot- ted again. A coloured bead gives A better Anish than a knot, and, the use of an elastic cord. would be best

The uses for such a form of in- ... sulation are many, and there are obviously many others to which it could also be applied, especially as the tubing can be obtained in three sizes, thus forming a range which would cover articles vary- ing in diameter from 3/16in. to lin. Tubing ; in diameter. which will cover articles from 3/16 to 5/16ta: fh diameter, costs 4d. per foot; jin, tubingi which would cover, articles from fin. diameter. costs 5d. per foot; in tubing, which Will cover articles from in to lin. in diameter, costs 6d. per foot.

Tho Literal Truth Salp: Fee Brown's got a moter-car."

Snap: "Yes, his rich uncle gave it to him.

Shap: Why. he told me he put all the money he had into it."

Snap: "He did. He bought five bob's worth of patrol for it"

Simple Suggestions

Some Simple

CLEANING ALUMINIUM

A clean rag soaked in turpen-· tine will quickly remove dirt and grease from an aluminium crank case, and will at the same time

· give a ·· lacquered finish to the aluminium. This method also seems to prevent any future: dirt and grease from sticking so rea" dily, to the surface as when it has been cleaned with paraffina or petrol A mixture of metal polish. eucalyptus oll and whitening 1 also excellent for polishing aluminium, and is used by many motorists to give a good finish after petrol, or parafin has been used for cleaning away the dirt,

KNOCKING OUT BOLTS

Never hammer, la projecting thread to shift bolt. Hold a plece of lead or wood over the end of the thread or knock the bolt out with a wooden“ mället

*

or copper hammer so as to avoid damaging the thread.

· EASIER, GARAGING

When garaging the car at night' one usually has more time at one's disposal than when taking it out the next morning. 'It is often, therefore, worth while re- versing the car into the garage so that it can be driven straight out If it should be needed in a hurry. Reversing into the garage is made more simple by painting a white line down the centre of the run- in. By this means much man oeuvring will be avoided and the position for reversing can be found almost immediately.

This plan is obviously not ap- picable to all garages, but a simi- lar idea could be applied by whitewashing any spot where one

has to lock the wheel right over." When a turn into a drive gate is situated in a fence or bedge, and is not very easily distin- guishable, some people have pain-- ted a white ring rotand a tree or other suitable object, от the opposite side of the road to their drive gate, in order to pick out the exact turning potit at night..

TUBES

Owner-drivers who change the air tubes themselves do not al-

ARGIATHOPNYCROFT WITH

DEAL DIRECT

"ways appreciate the necessity for cure in properly distributing the French chalk which they put from side the tyre itself. The amount. of friction arising between the inside surface of the outer cover and the outside surface of the air tube is enormous, and the object of the French chalk is to lubricate the two surfaces which thus come in contact. A round tin with small. holes... bored through the lid, like a pepper pot, is excellent for distributing the chalk evenly.

| PROTECTING THE HANDS

It is a good idea to wear a patr of thin cotton gloves when mak- ing any repairs or adjustments, for it usually takes several days before the hands are thoroughly cleansed of all, and so forth. Dirt is easily removed from the smooth part of the skin by petrol, parafin, ammonia. turpentine. soft soap, dry soap, and some other substances, but many of these roughen the skin, and few of them contain antisep- tics Abrasions are often-sustain ed in handling tools and doing odd jobs, and should any organic matter from the road enter a skin abrusion blood poisoning may easily result. The real difficulty In keeping the hands clean is con- cerned with the interstices round the nails and the indentations in the skin on the knuckles. These. should be smeared with vaseline or soap before any job. likely to soll the hands.

LOOSE NUTS

If a nut should work loose and yet is on such a bolt that no or- dinary adjustment will necessitate its removal the end of the bolt may be slightly burred over with a light hammer. A very light. spreading of the metal will pre- vent the rut shaking off, yet à spanner will easily bring the nut over the burr when required. "If the nut a large, and regularly re- quires removal, put a spring was- her or locking washer behind it and cover the thread with paint. If a small nut, painting it over with clear varnish will sometimes have the desired effect.

TRANSPORT

THORNYCROFT

SIX-CYLINDERED

COACHES & OMNIBUSES

MOTOR

DIESEL

@

VEHICLES

PETROL

Pioneer Manufacturers of Commercial

Full Range of Spares carried in Hong Kong and Shanghat,

4 or 6 Wheels

4 or 6 Cylinders

80 Cwt to 10 Ton Loads

20 to 70 Passenders

JOHN L. THORNYCROFT & CO. LIMITED,

Pioneer Building, Hatkan Road. Kowloon.

TEL. 56159,

TAUSTA THORNYODUFT WITH Y300 TPASSI