THE MODEL CAR POSITION

Author

admin

THE MODEL CAR POSITION

THE model car position in this country is in a healthier state than it has ever been thanks mainly to the lead given by D. A. Russell, M.I.Mech.E.’ the tireless managing editor of the A eromodeller. Largely due to his influence, many British enthusiasts are constructing fast petrol driven model cars, and r.t.p. meetings are held .once a month in London by the British Model Car Club. Nevertheless, although model-car racing is now properly organised over here, as it has been in America for some time, racing folk have not yet taken up the pastime as an antidote to the petrol-less era, which has put paid to the real thing. The B.M.C.C. recognises two classes : Class I for models of up to 6 c.c., the wheelbase of which does not exceed 15 in. and track 9 in., and Class II, for models of 6 to 10 c.c., the wheelbase not exceeding 20 in. and track 11 in. The Model Engineer has organised a competition for designs for working model racing cars, limited to a maximum length of 2 ft, a track of 1 ft., and a weight of 10 lb. The first prize was £.5 5s., and the result should have been announced by the time these words are in print.

Up to now non-scale models seem to predominate, the most notable exceptions being Mr. Russell’s excellent enclosedcockpit, record-breaking Auto-Union and S.S. ‘100″ stripped sports 2-seater. In the main the non-scale models are quite decently proportioned and look far more like the real thing than the average American model ; we sincerely hope the new definitions recognised by the B.M.C.C. and referred to in “Club News” will not encourage the entry of mechanised trucks.

Speeds here appear to be around 15 -55 m.p.h., compared with 90-100 m.p.h. reported from America. “Solid” transmission, necessitating a push-start, is apparently usual in America, but in this country the centrifugal clutch is freely used, making proper starts (and coasting after the engine has cut) the order of the day. Two designers have decided that even this is not ideal, because it is not possible to run the engine up to full-bore on test without the clutch coming in, so they propose to use dashpot clutch control, the dashpot giving gradual engagement of the friction surfaces when all is well in the engine department. Most people seem to prefer moderntype cars as a subject, but the possibilities of old-style, track-type cars should not be overlooked, especially as they often used disc wheels and were well cowkd, making for easy modelling. Moreover, external chain drive should be a fascinating plaything and would provide a ready means of altering the ratio of the final drive. Admittedly, the recent scrapping of an ” unlimited ” class by the B.M.C.C. may somewhat discourage such types. We would like to see banked tracks in the future, as adding to the interest and, perhaps, offering better running conditions. And we hope soon that duration records will be recognised—Edgar Westbury has assured us that tiny i.e. engines will function indefinitely, if properly designed and lubricated. The B.M.C.C. already has an electrical timing set, although this, T. W. Loughborough pointed out in The Model Engineer of April 12th last, can only hope to be accu

rate to about 1 part in 100, i.e., to the nearest 2 m.p.h.

Although petrol-driven models are at last flourishing, the non-working smallscale model still presents a pretty problem. Rex Hays, of Steyning, has been modelling small racing cars for his own and his friends’ amusement since 1921. During the war professional modelling for the Admiralty has kept him busy, but recently he indulged hi a few more racing-car models, which particularly pleased Capt. Robert Fellowes. These included E.R.A., Mercedes-Benz, AutoUnion, Maserati and Alfa-Romeo G.P. cars, etc., and the interest aroused has been stupendous. Hays has been working 14 hours a day on official modelling and on orders for racing cars. He has supplied eight models to one well-known Bugatti driver, a model of a 1938 Mercedes-Benz for Mrs. Seaman, and has on order a ” 3.3 ” Bugatti, while ‘models of touring and saloc n ears are also in demand. His models cost, on the average, 12 2s. each with driver. Then C. Porthumus, of Walton-onThames, has been working on a detailed model of a ” Monoposto ” Alfa-Romeo, with a view to publishing plans and building instructions. Finally, G. IL Deason, of Wylain-on-Tyne, has made some very effective small models in wood, to 1/30th scale, notably of the 4+-litre ex-Birkin Bentley 4-seater and E.R.A. cars. This is in addition to a 10-c.c. petrol-driven model of the Leyland-Thomas, designs for which, we understand, will duly appear in Practical Mechanic. Deason hopes to follow this up with a petrol model of the famous 4-cylinder Thomas-Special. So far as his ” solid ” models go, we can do no better than publish in full his own remarks on how they are built, and thank him for allowing us to do so. He writes :

Let it be said at the outset that the following notes on model-car construction are not intended for the expert and experienced Model engineer, but rather for ordinary folk like the writer, with but mediocre skill and very limited equipment, whose enthusiasm for cars engenders the urge to reproduce them in miniature. It matters little whether the model be a small ” solid ” or a power-driven competition job, there is a satisfaction in viewing the result in three dimensions that the finest picture cannot give. And since interest in this branch of modelmaking seems to be growing rapidly, as well it may, a few ideas may not be out of place.

Let us deal with the “solid,” or static scale type. The smallest practical scale would seem to be around 1/30th, giving models some 4+ in. long, into which a surprising amount of detail can be built. Some very excellent drawings to this scale have appeared from time to time in The Motor, in Laurence Pomeroy’s “Milestones of Speed” series, giving accurate side and front elevations which are of immense value. But no great difficulty should be experienced in producing one’s own drawings from photographs, given some known dimension such as tyre sizes or wheelbase. The bogey of all scale car modelling is definitely wheels of the Rudge ,„variety. It is held by some constructors that disc wheels are permissible, but the writer has never held this view, and is still struggling to produce something nearer realism. Tyre sizes in the 1/30th scale class are around 1-in. to 11-hi, diameter, and a visit to the nearest Singer sewing machine shop will produce rubber rings . of these sizes very cheaply. More realism can, however, be achieved by building up the wheels from discs of 1 ram. ply, or similar material, cutting two main discs full size (i.e., maximum tyre diameter) and spacing them with a ring of slightly smaller diameter. Additional rings of alternating diameters are cemented on either side, thus building up a tyre with a ribbed tread, the final tyre walls being of balsa, which can be turned simply by mounting the wheel in a drill chuck and sanding to shape. Alternatively the main wheel discs can be of scrap sidescreen material, through which the brakedrums can be seen, and upon which spokes can be scored and Indian inked.. This method is satisfactory for larger sizes, sheet rubber inserts being employed for power-driven models to give a non-skid tread. (Incidentally, the writer saved himself much labour by constructing an adjustable cutter for these experiments, on the lines of a joiner’s expanding bit.)

Wheels apart, there are no snags in ” solid ” model car building. The sleek ” one-place ” racing car is obviously jam to anyone who has produced, say, a 1/72nd scale Spitfire. A note or two follows, however, on a simple method of producing a 4-seater of the Bentley type. Avoid, like the plague, any direction which tells you to “take a piece of yellow pine,” or any other fancy timber. You won’t find any nowadays, and your enthusiasm will be blunted. Take, rather, a block of wood of suitable size, avoiding the more obvious knots, and take heart

from the thought that a good grain-filler will cover a multitude of sins if ever you reach the painting stage. Mark it out in profile, plan and end elevation, including in the profile the full depth of chassis and the radiator. Saw out with a fret-saw or coping-saw, and then carve and sand-paper the block to conform to the curvature of the body-lines. The radiator can be partially finished’ at this stage, at any rate, in general outline, and be parted-off later for finishing. If the prototype has a normal tuivalanced chassis and I-elliptic springing, cut side members of light-gauge brass, drill for spring anchorages, tie-bars, etc., and screw to the main block, which can be recessed to take them if necessary. The body can now be hollowed out. For quick results use a i-in, bit, bore through the block at suitable points behind the sCuttle, and remove the surplus with a chisel. A ply or card floor can be fitted later. At the scuttle section, bore about 4/5t1is through from the underside, leaving the arch of the scuttle intact. Cut away the bonnet portion completely between scuttle and radiator, down to the sidemembers, and keep the cutaway portion as a former for the metal bonnet. A platform is thus left to support the dummy engine. Springs and axles can be assembled at this stage. Springs can be made from laminations of thin brass,

or scrap watch-spring, the master leaves softened at the ends and turned over to form loops for the shackle pins. Bind with thread and coat with glue or shellac. Spring shackles are made from thin brass bent up in one piece, roughly in the form of the letter P, pinned with shortened domestic pins.

The amount of detail built into the engine must depend on the builder’s skill and inclination, but it is worth noting that some beautiful 1/48th scale aero engines have been described in recent numbers of the Aeromodeller, in which it has been found possible to include accurate representations of camshafts and timing covers, carburetters, superchargers, and even plugs and leads. Details generally can be left to the individual, and a good rule is “If in doubt, leave it out.” One is, after all, doing the job to please oneself, and a bold and characteristic outline can be very pleasing in itself, even if it doesn’t satisfy the super-scale fans. It is amazing, however, what odds and ends can be utilised to obtain effects. Radiator honeycombs, for example, may be made from the coarse gauze used for protecting the sticky side of corn-plasters I A perfect Bugatti radiator can be made in 15 minutes from 1-in, plywood cut to the

classic shape, bound round the edge with silver foil, faced with gauze blacked with Indian ink, and the red medallion cut from the shiny cover of the February MOTOR SPORT! Spring-spoked steering wheels have a copper-wire rim sdldered to a brass” X,” with centre boss cemented over the head of the upholsterer’s pin forming the column. Your wife’s adjustable leather punch cuts various holes in instrument boards very neatly, behind which is a layer of cellophane and white or black card suitably “calibrated.” Hoods, tonneau covers, etc., are cut from the matt black paper used for wrapping photographic paper, and very expensivelooking upholstery can be produced by covering the card or metal seats with overlapping strips of black or coloured passe partout, the kind with a grained finish. The Bentley’s headlamps were the ends cut from the rubber bulbs of ” Ephedrine ” droppers, with wire rims and gauze stoneguards, and the twin klaxons were small brass wood screws with the heads cut off, screwed into short lengths of dowel.

One final word. Do not attempt to paint letters or racing numbers by hand. The model shops sell transfers in all sizes which add greatly to the look of the job.

There is much to be said for building to a single scale, and choosing subjects to a plan. Thus a collection of one marque, or a historical series of Grand Prix types or Outer Circuit care, can be built up progressively, which will be easy to house and ten times more interesting than a scrap-book in later years. One of the writer’s unrealised ambitions is to own a complete collection of 200-Mile Race competitors, in miniature, if ever sufficient data could be collected.

Enough has been said to show that no great skill or cash outlay is necessary to construct these intriguing models, at least to one’s own satisfaction, if not to exhibition standards, and photographic fans will find they open up a new avenue for table-top photography with a motoring flavour. It is greatly to be hoped that some attention will be given to this branch of modelling by the newly-formed British Model Car Club, and that a corner might be found in MOTOR SPORT to depict readers’ efforts from time to time.— G. H. D.