From Drivem and Mechanics.
If you've noticed an error in this article please click here to report it so we can fix it.
TEN SHILLINGS WEEKLY is paid for the best communication received, and one penny a line of ten words for anything else published, with an allowance for photographs.
Workshop tips and smart refiairs ; long and successful runs ; interesting photographs ; all are suitable subjects. We will knock your letters into shafie and will firepare sketches, where necessary, before Publication, The absence of a sketch does not disqualify for? prize. When writing, use one side of the paper only and mention your employer's name as a guarantee of bona fides. Neither pour own nor your employer's name will be disclosed. Payment will he made immediately after publication. Address your letters to The Editor, THE COMMERCIAL MOTOR, 7-15, Rosebery
Avenue, London, E.C.
Annual Bonuses are given to the most successful contributors.
[980k] Tien " writes ;—" Place horn, hoof, bonedust or shreds of leather, together with the article to be case-hardened, in an iron box and subject tiv whole to a blood-red heat, then immerse the article in cold water. A case-hardening mixture is three parts of prussiate of potash to one part of sal-anum,mac mixed ; or two of sal-annuoniac, two of bonedust, and one of prussiate of potash."
Removing a Tight Bracket.
The sender of the following communication. has been awarded the Ws. prize this week.
 " J. Mel)." (Fort William) writes :—" I had occasion recently to remove a brake bracket fitted to a hark-axle which most obstinately resisted all the usual methods of re moval. Still, needs must • when the devil drives,' and accordingly we had resource to the following method.
" I. got an old driving chain and placed it over the back of the bracket, and by means of a boll and nut through two of the links, made a chainloop big enough to allow of the insertion of a jack. By this means a tremendous pulling force was brought to bear on the bracket, and a few taps with a heavy mallet brought the offender off in fine style. This little scheme can also be utilized very effectively for taking off chain aria road wheels when a wheel puller is not to hand," Suggested Improvements to a Winter Tread.
 " H.M." (West Bromwich) writes :—" I must congratulate J.G.A.' on his clever device for a winter tread, which was published in your Drivers' page of 14th December last. [Letter No. 972, entitled a Winter Tread.--En.] At the same time I forward one or two suggestions which would, in my opinion, render the band even more serviceable than at present, parI icularly as regards locating it on the driving wheel. Three or four strips of leather riveted to the belt would be all that is required to prevent the band coming off through sideslip. As a further improvement, I should suggest placing alternate blocks of hard wood and rubber diagonally across the band. As many of my fellow drivers may not be fully aware of the properties and natures of hard woods and their utility for brakes and similar purposes. I send a few particulars which may be of service to them.
" Amongst British woods, the oak, elm, poplar and willow are the most suitable for such a purpose as this. The peculiar hardness of the Australian jarrah and salmon-gum make them particularly suited for brake purposes, while the iron bark and the blue gum of Tasmania are also exceptionally serviceable. Hardness and durability are the desirable qualities, and the above woods possess them in exceptional degree. They are readily obtainable in almost every timberyard."
Hints on Holding and Machining Discs.
 " A.C." (Forest. Hill) writes :—" I have frequently experienced difficulty in holding discs of varying diameters in the vice, when machining, drilling, slotting and so forth. When held between the ordinary flat jaws, the work slips and twists, and accuracy becomes impossible. To obviate the difficulty I have designed a simple little jig forming part of the vice equipment, which can be put in or out of action at. any time. Briefly, it consists of four round cast-steel pins, screwed in. Whitworth at one end, and slotted to take a screw-driver at the other. These are screwed into holes drilled and tapped in the top part. of the vice-jaws, the work being held between the pins, and the vice tightened up in the usual way. By the adoption of this simple device the disc is securely gripped, and can he carried about the shop for mark
ing off without risk of displacement. The sketch fully explains the position of the pins of which two sets are shown. Sometimes it is necessary to, turn a disc perfectly true all over, and the most simple way to do this is to grip it in the jaw-chuck, and to face down one side. This machined face should now be sweated on to a piece of rod brass, preferably about 1 in. to 2 in. diameter and flied or turned quite flat on the end. The whole arrangement can then he held in the chuck and machined all over without trouble."
Gossip, Gearing and Worms.
[9,1j GENERAL" (London) writes:— "Having had a driving experience dating back to the old 'Vanguards, I think I ought to know a bit about bus design as far as comfort is concerned. If some of the
steamers ' could relate their experiences, and tell of their little troubles with ' donkey-engines, • and of blisters that won't come off, we should perhaps get more consideration.
•• There is a story going the rounds of a Tilling bus, which, owing to a dry wheel-bearing setting op a sclaeak, was pulled up by an agitated lady. She rated the driver soundly, and informed him that he had run over a dog, and ' ought to be ashamed of himself.' He now answers to the name of ' Bowwo 11'
As regards the new buses, a worm-gearing is, in lay opinion, far and away the best for the hack axle.
They are less noisy, and some machines two and three years old are still running with the original worms, due, I believe, to the fact that they get positive and direct lubrication. The chain gearboxes are not so easy to manipulate as the straight-through change. " Some time ago ill the D. and M.' pages, I criticised the provision made for the driver's comfort, and the 1912 types show little improvement. For protection from the weather there is still the same old tarpaulin, string and kitchen-dresser knobs, and maybe an extra in. thickness of stuffing in the seats, so perhaps we have something to be thankful for.
" It is remarkable to me that motoreab drivers should have come in for so much consideration for their comfort. What with canopies, windscreens and special little shields to protect their ears from the wet, For surprised that some of the owners don't pro‘ide their men with hot-water bottles and Thermos flasks."