CONCERNING READERS' LOG SHEETS.
Page 26
If you've noticed an error in this article please click here to report it so we can fix it.
"The Skotch " Goes Carefully into Figures Submitted to Him by Hauliers who have Recently been Using "The Commercial Motor" Form.
IR diseussing last week the figures given by a reader, whom we chose to call "Mr. Haulier," we found that the running costs of his two 4 ton lorries worked out as follow :—No. 1 vehicle : Petrol, 5.8d. per mile ; lubricants, 0.11d. per mile;
maintenance,_ 4.5d. per mile. The corresponding figures for No. 2 vehicle were : 3.05d., 0.19d. and 0.31.d. Our own sheet of running costs, which last appeared on page 59 of the issue for August 30th, gave 3.44d. per mile as the cost of petrol, 0.77d. for lubricants and 2.40d. for maintenance; it would, therefore, appear that, while both the lorries belonging to "Mr. Haulier ". are economical in their consumption of lubricants, No. 1 is rather expensive in petrol and maintenance: No. 2, for the week in question, is most economical throughout. . None of the figures is likely to be a true indication of the actual cost of running of the wagon con cerned; the high expenditure in the case of No. 1 and the low cost of No. 2 may equally be due to particular conditions appertaining only to the week in question. If the same ratio was apparent week after week as regards petrol consumption, then the owner would be justified in calling the attention of
driver No. 1 to the circumstances ; indeed,., not the
least of the many advantages which regular compilation of these log sheets affords is the facility for checking one driver against another in this manner. It may be, for example, that this excessive fuel consumption is due to the fact that the driver of No. 1 vehicle is partial to petrol as a medium in which to wash his hands ; alternatively, it may be clue to the fact that he has been allowing his engine, to run during prolonged stoppages, of the vehicle, or there May be other similar causes, similar in that they are preventable by personal attention to the matter on the part of the driver. Experience has shown that the best method of ensuring economy in this direction is by the payment of a small bonus to the driver, and I certainly recommend this course to every owner of two or more vehicles.
Above all, however, as I suggested last week, these aimost extreme differences in cost as.between one vehicle and another, and as between both and fair averages, may be due to special circumstances, occurring during the week in which the record was taken, and unlikely to recur for a long time. The only safeguard against arriving at wrong conclusions is to keep continuous recordsiand to take an average over a long period, in just such a manner as has been done by another reader, whose results have been placed in tabulated form and accompany this article. It is not a troublesome matter to take out these results once a quarter, as has been done in this case. The mileage for the three months is a little over 3,000, and the running costs', average 3.62d. per mile for petrol, 0.5d. for lubricants and 2d. for maintenance, which figures compare reasoneibly with those given in our own table before referred to. Maintenance costs, it will be observed, are comparatively low; this is probably due to the fact that more than ordinary care is taken of the machine with which the records are concerned.
On referring to the tables of running costsz the reader will observe that there are still two items not yet accounted for, namely, depreciation and tyres. The former may be calculated by taking the first cost of a tteiv vehicle of the type in question and dividing it by 125,000, which is assumed to he the average life, in miles' of a heavy motor vehicle.
' Sonic in good hands, last longer ; others find their way to the scrap-heap before that mileage is covered. e28 Even in the former case the owner will do well to write the cost off in that period of running, whilst the man who ruins his vehicle in covering a less mileage has, presumably, some compensation for the rough usage to which it has been put. By reckoning depreciation on the first cost of a new vehicle, the haulier is saved the necessity of making abstruse calculations as to the real value of a vehicle which he has bought second-hand, and, on the assumption that his purchase was a reasonably sound one, the figure is quite accurate.
As to tyres, the haulier will only begin to have an idea of his expenditure per mile under this head by the time he is beginning to replace those which were on the vehicle at the time when he acquired it. If they were new, this means that, in most cases, nearly a year will elapse before he will be able to make accurate calculations. In order to ascertain those costs, he has only to keep notes of the dates when new tyres are fitted and when they are removed. From his accumulated log sheets he can then ascertain the mileage which each tyre has accomplished, whence an accurate estimate of the cost per mile can be obtained. In the tables I have put tyre costs in on the basis of from seven to eight thousand miles per tyre. My figures have occasionally been challenged—by tyre manufacturers, but never by hauliers—as being high. My only answer is that they represent average results obtained by many users in general cross-country haulage. In favourable circumstances they may be improved upon, which is so much the better for the user, but in this connection I would strongly recommend that tyres be not worn too far down ; the resulting saving under the heading of "cost of tyres " will be more than offsetjay a corresponding increase, under the item "maintenance," as the more a tyre -wears down the greater is the vibration experienced by the chassis, owing to reduced cushioning.
It will be appreciated that the above remarks concerning tyres refer principally to solids. With pneumatics, the data for calculation are not so easily. acquired, owing to the fact that spare tyres ale usually kept and frequent changes Take place. The only method, whereby tyre costs can be ascertained in con-. nection with vehicles mounted on pneumatics, is to keep a careful ecord of expenditure on tyres over a fairly long period, dividing the total thus obtained by the mileage covered during that time, thus obtaining an average figure. THE SKOTCH.