Is Tyre Regrooving Wise?
Page 47
Page 48
If you've noticed an error in this article please click here to report it so we can fix it.
IN your issue dated November 2, there appeared an article entitled "One-third More Wear from Tyres," which I read with some interest.
Generally speaking, tyre maintenance is carelessly .-applied and is consistent with the casual attitude of the average motorist to his tyres. There are, of course, many
• goods-transport operators who realize the importance of tyre cost per mile and place considerable emphasis on maintenance to this end, but by and large, I am in agreement with the implicatiOn in the article that numbers of operators would obtain More miles from their tyres if they would devote a little more attention to them and could insure more tyre-conscious driving.
, Whilst of the opinion that any article which draws attention to the need for better tyre maintenance is serving a useful purpose, I do not agree with the suggestion that sound covers should be grooved at that stage of their life where the tion-skid
tread depth is disappearing, and in this connection I consider the article to be • misleading.
The practice of grooving tyres at'a
• certain stage •a wear is an accepted feature of tyre maintenance under certain conditions and, as the article rightly points "out, is an approved factor in the tyre-tpaintenance policy of the majority of municipal and company owned public transport undertakings.
The point is made that such undertakings in most instances obtain their tyres on a mileage-contract basis, and that tyres so supplied are generally serviced and maintained by a fitter employed by the tyre manufacturer. What is not made clear is • that, in addition to supplying and maintaining mileagecontract tyres, the tyre manufacturer provides tyres which are specially designed for public transport service and incorporate the feature of a specially heavy undertread to facilitate grooving.
The undertread on such tyres, which may have some moulded imprint to identify them, bears a much greater relation to the nonskid-tread depth than does the undertread on the standard tyre of similar size, consequently, the reference in the article to an undertread in excess of 50 per cent of the nonskid-tread depth is incorrect unless applied to the specially designed tyre supplied for mileage-contract service. In this the undertread depth is occasionally equal to, or even greater than, the nonskid-tread depth.
It has already been mentioned that the purpose of this extra-heavy undertread is to facilitate grooving, and it must be appreciated that the tyre manufacturer under mileage-contract-terms is selling miles—.not tyres. The heavy undertread, assisted by grooving, provides for greater mileage per tyre. The number of times any tyre can be grooved will be determined by the amount of undertread available and the genefal condition of the particular tyre, which will generally be withdrawn by the service fitter at that stage of wear considered to be most suitable for submitting the tyre for complete reconditioning by the manufacturer.
To introduce the practice of grooving tyres other than those specially designed for such purpose would be to subject the sound carcase to greater risk of serious damage, and would contribute to total failure. Surely, it would be far better to devote more attention to maintenance before the non-skid tread depth is worn away? By paying particular attention to inflation, load, load
distribution. correct alignment, mating of. twin assemblies, regular rotation of tyre position (including the spare) and the removal of flints, etc., more. miles: per tyre would be obtained without the need for grooving, and by such methods the casing would. be preserved for complete reconditioning and further economic Service.
R. 'EDWARDS,
Production and Service Manager,
Wembley. Middlesex. (For Tyresoles, Ltd.)
TYRE TROUBLE WITH TWO-P1ECE • WHEELS • THE article entitled "One-third More Wear. From Tyres" in your publication dated November 2 aroused more than our usual interest in an .always supremely interesting journal.
• We have been operating Bedford coaches for many years, but on our post-war machines have experienced considerable trouble with excessive wear on the side walls of the tyres, due to the cutting action at the joint of the split rim of the twopiece wheel.. Our pre-war machines were quite free' frotn this trouble, being equipped with the Sankey three-piece wheel.
The writer took, this matter up with both the wheel manufacture and the Vauxhall concern some considerable time ago, and offered to purchase three-piece wheels, but was told that these were not available for the vehicles in question. The only advice that we received from the vehicle maker was to file a radius on the edges\Of.the split rim in contact with the outer wall of the tyre, We had already done this, but with very little success.
Further to this, the Michelin Tyre Co., Ltd., kindly supplied a metal insert to be placed between the split rim and the tyre wall, but so far a suitable metal has . not been found, as these inserts crack after a few thousand miles in service.
The answer would seem to be a return to the threepiece wheel, but this the manufacturer says cannot be supplied. In view of this, therefore, we would be interested to learn what remedies other than these mentioned can be applied; they would be received with sincere gratitude.
F. K. SANSAM, Director.
(For Sansam Bros. (Sheffield), Ltd.) Sheffield, 9.
A DRIVER'S VIEW ON DENATIONALIZATION
MANY drivers are taking a lively interest in the suggested return of nationalized haulage vehicles to private enterprise. Some take the view that where a former owner does not wish to return to the industry, and following th.:. suggestion that a greater tonnage would not be permitted to those concerns which are now running free-enterprise fleets, the crews may become redundant while waiting for the hammer to fall on the vehicles they are driving. Others suggest that they may not like the new purchasers and that, in any case, there would have to be a time lag before a sale took place. One man said that as there are 60,000 drivers in British Road Services, why had they not been consulted?
I have read that the Norwich branch of the Transport and General Workers' Union has candidly stated that the drivers want no part in the change. I must aeree B13 that conditions under the B.R.S. are not so much different from those that existed under private enterprise. It is true that there has been one dispute of any importance, but that has been settled, and now we are informed that the B.R.S. is showing a profit.
In the best interests of the Nation, I do not think that we should monkey about with something which, believe, may cause trouble in the ranks, for there will be trouble if a redundancy occurs, and, frankly, the drivers are not looking for it.
Hounslow. Wi F. YoRA'f i.
WHY NOT YOUNGER CONDUCTORS?
ALTHOUGH I agree with you in your article "These Men are Wanted," which appeared in " The Commercial Motor" dated November 9, I would like to comment on the way employment is offered by the bus companies.
When advertising, many companies display notices in their buses,, to the following effect: "Conductors wanted, free uniform, holidays with pay, cheap travel, canteen and good pay."
Surely, the attitude of most men towards this is that the company is making thework attractive by the uniform, cheap travel, etc., and not by the pay. If it were good, then the actual amount would have been stated.
Why not have an advertisement which gives the basic wage also the average with overtime and Sunday duty? My age is 20 years and 3 months, and I have just completed my National Service. I have been collecting and studying timetables, routes, fares, etc., since I was eight years old, and it has been my ambition to be employed in road tranSport. My employment before I enlisted was as a booking clerk on the railways. I have tried to secure similar employment in road transport without success. I then endeavoured to become a conductor, but was turned down because-I was not 21.
Surely, if the age were to be lowered to 20, the bus companies would gain a number of suitable men, who, like myself, are either without a job or are wanting something better.
Potterne, Devizes. ALAN P. MEAD.
WHICH GEAR FOR STARTING?.
WITH regard to the controversy over, the use of first " or second gear for starting, this depends on the type of vehicle, its engine power and, above all, on the driver, with due regard to operating conditions, load, etc.
If one has a 9.6or 9.8-litre power unit and no load, one can start with ease in second gear, but with a Toad of 12-22 tons, first gear is essential.
Your journal is the voice of the transport industry, in every way, and may free enterprise, with incentive and good conditions, prevail in our, industry.
Great Yarmouth. ROBERT NORMAN.