OPINIONS FROM OTHERS.
Page 31
If you've noticed an error in this article please click here to report it so we can fix it.
The Editor invites correspondence on all, subjects connected wills the use of commercial motors. Letters should be on one side of the paper only and typewritten by preference. The right of abbreviation is reserved, and no responsibility for views expressed is accepted.
Rail Rates 100 per cent. Above Motor Haulage.
The. Editor, THECOMMERCIAL MOTOR.
[1934] Sir,—We have just received per Midland -Railway 11 tons 9 cwt. screws from Purrteet to MAL depot at Wandsworth Road, a distance of about 20 miles. On arrival, we were asked to pay 50s. (3d. per ton, which we refused to pay. After taking this matter up with Midland Railway chief depot at Derby the charge was reduced to :39s: 5d.per ton. These goods could have been carted by motor lorry at 18s. per ton, delivered to our warehouse.
We also have 400 tons hardware (unissued Government stores) lying at Dideot, for the carting of which the Great Western Railwayquoted 53s. 4d. to 62s. per ton. We are, therefore, having the goods brought up by. motor lorry dt a total cost of 28s. to. 30s. per ton.
In face of these figures' one can quite understand the railways trying to get read haulage powers.
Haulage contractors requiring return loads front Did-cot, please communicate with us at 125a, Hamilton Road, West Norwood.—Yours faithfully, HAMILTON TRADING CO. HAMILTON TRADING CO. W. BRADSHAW', Co.,
Bearings and Their Heat Treatment,
The Editor, THE COMMERCIAL MOTOR.
[1935] .Sir,—With reference to the above subject it would appear that Mr. Barfield has missed our point. It is the peculiar construction of the Hyatt bearing which allows it to 'deflect under shock loads. The illustration produced in your issue of March 21st was intended to illustaate the effect , of very heavy overload and to show that the Hyatt flexible roller deflects and absorbs the shock load Rather than passing it on to the housing or races. We do not suggest deformation is due to improper methods of heat treatment, but that a hollow cylinder is able to deflect more easily than a solid one.
" Designer " raises a number of interesting points If there is misalignment in the shaft or housing, that is the result of had workmanship, and no antifriction bearing will give full and efficient service under such .conditiona.
We are afraid that " Designer" is labouring under a serious misapprehension when he states that flexible roller bearings wear the shafts. This is most certainly sot the case if our directions have been carefully observed. We stipulate certain shaft hardnesses for roller operation, and where these have been adhered to, and provided the bearing has not been overloaded, no wear has taken place.
Ford cars have four bearing a , on the rear axles • with rollers running directly on the shaft. Hudson and Essex cars have bearings operating on the shaft, and there are many others we can mention without referring to hundreds of line shaft installations which have been running for many years without a trace of wear in the shaft.
Recently we heard from a large user of cranes that. Hyatt bearings had operated on the crane shafts for fifteen years Without giving a moment's anxiety.
It would be interesting if " Designer " would give a concrete instance where wear bag -taken place on the shaft due to flexible roller bearings, bearing in mind that the user respected our recommendations as to shaft hardness and mounting.
He also generalizes on the absorption of noise. We, on the other hand, make a definite statement from actual experience that Hyatt bearings do absorb noise in gearboxes., Deflection of the shaft through roller flexibility would only occur under heavy shock loads and, therefore, the gears would suffer no misalignment when running normally. When under shock load, the capacity of the bearing is such that this deflection is only of minute proportions and no more than would cover the inaccuracies of gear-cutting. We should be glad to meet " Designer " personally, and show him at greater length, and in more detail, examples of Hyatt bearing installations which would contradict, without exception, all the paints he raises against them.—Yours faithfully, For HYATT, LIMITED,
• J. COATES, Director. 56, Victoria Street, London, S.W.1.
Tension in Chain Tracks.
The Editor, THE COMMERCIAL MOTOR.
11936] Sir,—I was interested in your remarks in last week's issue of The C oramercial Motor, about the fitting of creeper tracks to the rear wheels of six-wheeled vehicles.
I can quite visualize a system such as you suggest giving satisfaction on fairly compact snow' where hard " knobbly " obstacles are unknown, but for general use over rutted andbroken ground there appear to be several .serious drawbacks: The principal one, I think, would be' the excessive tension in the track when an obstacle of sufficient height to raise both Wheels off the ground is being absorbed between bothwheels. The tension• under these conditions could be much greater than the total weight of the machine.
The introduction of a spring device to lessen this seems at first sight to be practicable, but, with any sort of spring between the two wheels, trouble arises: when the machine is running in reverse. Some experiments were carried out in the 'U.S.A., I believe, but I am not aware of any definite result. Can your readers say if anyone in this country has studied this matter or if there is anyone capable of advising on such a problem 1—Yours faithfully, Ex TANK CORPS:
The Imported Char-a-bancs,
The Editor, THE COMMERCIAL MOTOR.
(1937) Sir,—We purchased a chassis of American manufacture last spring and used it in our business all the year with a 24-seater char-a-bancs body. During the winter we have had a few football parties) but we cannot say that this business has done mere than pay the wages of the driver. We are now being worried by the local Excise officers to pay a very large sum representing the import duty, and we feel that we have not had fair treatment over this. We cannot blame the people who sold us-the chassis, because we were told at the time how the law stood, although it is perhaps equally true to say that we did not fully appreciate all the intricacies and subtleties.
Why should there he a difference between an omnibus or char-a,-bancs faking individual passengers and collecting separate fares, and taking the same group of people as a party and receiving payment in a lump sum?
We are told it is so easy to "wangle the matter." but we strongly object to this line of action. We contend that the law, when it was framed, was intended to exempt from import duty those vehicles used by anyone as a means of earning a living, and not for private purposes.—Yours faithfully, M.O.