MOTORING NOTES

Nelson Evening Mail, Volume LXIV, 6 August 1931, Page 4

MOTORING NOTES

CONSTRUCTION OF CAR BODIES

PRESSED STEEL POPULARITY

(By Gerald Ely, London, for ‘Tho Mail”)

I was told the other day that tho [Austin Motor Company me selling four “Twelve-six” saloons with all-steel hod- ! ies to every saloon with a fabric body. 'This preponderance in favour of the all-steel body is interesting, because either typo of body is optional, and it shows that public taste is definitely swinging round in favour of all-steel bodywork as regards at any rate quantity produced cars. On tho whole, I think that this evidence of a- change of taste in favour of all-steel construction is in the best interests of motoring. The fabric body has certain advantages, tho principal of which is lightnoss, while it has the further point in its favour that, when it is constructed on the true Weymann principle, it follows the Hexing of the chassis without producing the squeaks and other noises that inevitably develop in coachbuilt bodies of the quantityproduced type. On the other hand, the fabric body lias several drawbacks as compared with the coachbuilt or the all-steel type. One of these is that it lends itself less to the. acquisition of that fine polish winch a, good cellulose finish bestows on an all-steel body. Another is that it is impossible to secure with fabric construction those flowing lines and engaging curves which characterise tho coach-built or tho all-steel body—particularly the latter. Finally, thero is the disadvantage that ft fabric body is more easily damaged and less easily repaired than an all-steel structure. DISADVANTAGES OF FABRIC If a car with a fabric body becomes involved even in a minor accident and the fabric is ripped, the chances are that in the subsequent repairing there will be more trace of patching than would he the case with an all-steel body whero it is only necessary to hammer out tho dent, or’ re-collulose tho scratches. Thero is another and much more important consideration. I should not care to bo in any sort of smash, but should such a misfortune overtake mo I think I should prefer that it should find me in an all-steel body. Experiments show that if you take a sheet of steel and bend it at right angles, the bent sheet will offer considerably more resistance to pressure in any direction than the original flat one, and a great deal more than wood, the resistance of which depends on the run of the grain. This fact was impressed upon me during a visit tho other day to the Pressed Sloel Company’s works at Oxford. Pressed steel, it is claimed, is steel at its lightest and at its strongest.

I saw great presses, costing many thousands of pounds each, take sheet after sheet of steel and press it and shape it as if it were cardboard. The fact that tho Pressed Steel Company make pressed steel car bodies for such well-known firms as Morris, Wolseley, Rover, Austin, Hillman and M.G. indicates that this method has the.sanction of the best engineering authority. •MEDIAEVAL TOUCH The enormous pressure exercised upon the sheets of steel makes every sheet harder, tougher, more resistant and' more durable than ordinary steel. Panels, wings, running boards, luggage grids, doors, all come out of. these presses, as do also tho complete sides of a car with spaces for windows and doom all pressed out of the one steel sheet. Welding completes the work begun by the presses. Workmen with facepieces suggestive of tho hood of an official of tho Spanish Inquisition—tho curious racks and jigs strengthen this suggestion of the mediaeval torture-chamber —take tho four major pieces of tho comploto pressed steel body and weld them into one complete shell. This shell is then glazed, fitted with removable upholstery, sprayed with repeated coats of cellulose paint, and two days after the sheets of metal were first fed into their respective presses, there appears a car body complete and finished within and without. In regard to tho upholstery I was impressed by two interesting facts during my tour of tho works. Tho first was the ingenious way in which tho difficulty of attaching upholstery to an all-steel body has been overcome.

When tho steel bodies are pressed out the dies are so constructed that they Icavo tiny channels in'various parts.of tho shell. These channels are filled with rolls of specially twisted papor of about £th of an inch in diameter. Onto these rolls of paper the upholstery is tacked and it holds tho tacks as firmly as if they wero embedded in wood. Another interesting point I observed was tho use of magnetic tack hammers by the girlupholsterers. They take a mouthful of tacks, put the magnetic hammer to their lips, sort out the tacks with their tongues so that the head adheres to the hammer, and with one blow tho tack is driven home. This operation is carried out with lightning rapidity. ONE-PIECE CAR The use of pressod steel for bodywork makes possible the one-piece car, and is thus an essentially modern trend. It is not so long ago that chassis and bodywork were seen to he two distinct things. The old type of body never did really suit tho chassis. It was a relic from the old coaching days when bodies wero perched high above tho wheels. Looking at car bodies of ovon three or four years ago it is obvious that their union to the steel chassis was a marriage of convenience rather than a true mating of kindred entities. Tt was a union of the ancient and the modern, of the old

and'the new—and the old often creaked badly, as is to be expected of age. In tho case of the all-steel body, there is no perching of it on the chassis by means of a heavy wooden sill. It ys fixed direct, steel'body to steel chassis, giving extra support to both, greater strength, bettor balance, lower lines and more headroom. It does away with the heavy internal framework that takes up passenger space, and it certainly increases visibility. Slim steel pillars replace bulky sideposts, and tho doors are less liable to jam because there is no wooden frame to expand and contract. To be rgally efficient a coach-built body must be expensively constructed. Tho all-steel body, lending itself to rapid processes —the Pressed Steel Company manufacture 200 bodies a day—is in no small measure responsible for the cheap motoring which we now enjoy. FIREPROOF CARS Although pressed steel construction Is likely to maintain its ascendancy whore tho low initial cost of a car is tho primo consideration and where a large output makes the cost of installing the highly expensive presses practicable, tho use of other materials will probably continue Where there is a desire to dopart from orthodox design and where cars aro turned out by the dozen per week instead of by the hundred. Fabric is still used to a considerable oxtent jn iho higher-priced cars in conjunction with aluminium panelling, while the claims of non-metallic substances, such.as fibre, compressed paper and similar moulded materials aro not overlooked cithor by the designers of motor car bodies. Such materials have bcon used with succoss in house construction, and as the averago car is supposed in a way to be a temporary homo from home, and tho same conditions of climate and tomperaturo apply to some extent, there is no ( valid reason why bodies should not be built at least partly with similar materials. In an example of this type of body rccontly illustrated in ono of the seimteclniieal journals, the panels wero described as being mado of a material in which asbestos fibre played an iinoo't ant part. This material can be moulded into any shape desirod and will, apparently, tako cellulose admirably. Jhe panels, roof and other parts necessitate a wooden frame to hold them together What strikes mo most about the employment of a material in which asbestos enters so largely is that it may pavo tho way for tho really fireproof car in the future. The danger of fire is not 'groat in the modern car, hut it would ho distinctly reassuring if the owner of a car knew that the isolation of his pas sengors and himself from all fire dangerspots such as tho fuel supply was ensured by asbestos, at any rate for a period long enough fo enable them to escape.