A USEFUL MISCELLANY.
Page 69
If you've noticed an error in this article please click here to report it so we can fix it.
Interesting Contributions from Our Driver and Mechanic Readers.
Two Practical Hints to Designers WE have often mentioned the fact that designers would do well carefully to study the page, as from it many very useful hints could be obtained. In some cases it will be found that designers will be inclined to resent suggestions coming from users, but such a policy cannot be too strongly condemned. The first of the two suggestions made by " A.13.C.," of Stockport (whose fell name we would like to have —En.), shows plainly that all designers at least cannot place themselves on a pedestal, and say that no one can teach them anything. The figure on the left represents a wing stay as designed, whilst that on the right represents the altered form as carried out by our cur. respondent. That on the left broke at a certain place—we need hardly point out the place at which the fracture occurred as that would be apparent to any technical man, excepting perhaps its designer. We are told that the altered form has given excellent service, the breakages which were frequent being reduced to practically nil.
Another suggestion from the same source is for holding the elbows of Autavaes, with which our correspondent appears to have had some trouble from their continually coming loose.
Broken Turnbuckle Rods.
THE breakage of a tie rod would seem to be a simple matter to remedy by welding a new piece on to the broken end and screwing it afresh, but in practice this is not so simple as it seems.
blatty cf the tie rods are fitted with right and left-hand threads where they screw into the turnbuckle, so that if the left-hand thread should be the one to break it is not always easy to get one cut on a new rod, unless a hollow mandrel lathe be available, left-handed stocks and dies being very rarely found.
"11.C.W.," of Nottingham, tellsus how he has managed to effect a very satisfactory repair in such a case.
In a small lathe, without a hollow mandrel, he turned an adaptor as shown in his sketch. A left-hand thread to suit the turnbuckle was cut in the lathe, whilst the large end was drilled up and tapped with a common righthand thread. The end of the tie rod was then screwed with ordinary stocks and dies to fit the drilled end of the adaptor.
Stripped Threads on Axles.
SEEING that there has recently been
some correspondence regarding the liability of nuts on the sleeves of rear axles to become stripped through the continual hammering of the rear wheels, a correspondent, " B.T.W.," of Forfar, tells us how he has found prevention better than cure, as a thread on an axle once stripped is not easy to recut. He points out that the frequent stripping of such threads may be taken as a sign that proper attention has not been given to it in certain designs.
Ho appears to have been unusually
unlucky in this matter, having had a number of axles strip, so when he tells us tlint he has greatly reduced the trouble, having had only two mishaps during the last six months with a fleet of thirty vehicles, we must imagine that his troables must have been considerably above the average.
His way of overcoming the difficulty is to insert a tube expander, similar to those used for expanding boiler tubes, after wasbering up and adjusting the net. By expanding the sleeve the nut
is made a very tight fit. He tells us that in some cases when a thread has stripped he was,able to expand the end of the sleeve so that the nut had to be split to remove it. He mentions the size of the expander he used on the Dennis 3-4 ton lorry as 21 ins.
The Easy Starting of Engines.
THE subject of easy starting still appears to interest our readers, although we had believed that all that could possibly be said on the subject had been exhausted. We seem, however, not to have finished with the matter yet, as fresh suggestions continue to come in.
Some of the latest ideas on the subject come from "E.L.B.," of Hull, who says that he has little trouble since he installed a garden watering can which can be placed on a gas ring so that the water in it becomes warm while he is doing other little jobs. He pours the warm water into his radiator, which has been empty all night, and allows a little of the water to run over the inlet pipe. This he has proved to be most effective ; he makes two further suggestions which, however, he has not tried. but which might be worthy of consideration.
As the greatest difficulty is always experienced in the morning while getting the engine started for the first time, he suggests that engines might be fitted with electric motoes for starting, but these, instead of being driven by batteries carried on the vehicles, might receive their current from the mains. Petrol engines on trollies would also be most useful.
A. Simple Remedy for Wheel Wobble.
THEremedy for wheel wobble lie- scribed by "OP.," of Norwich, although not new to the more experienced motor mechanic, may not be known to all, so we give it for whet it is worth, as wheel wobble appears to be a trouble that is on the increase with the introduction of the larger sections of pneumatic tyre.
The remedy simply consists of introducing a metal wedge between the front axle and the spring, so as to incline the axial line of the steering heads. It is essential, however, that the wedge should embrace at least two of the bolts which hold dawn the spring, otherwise the wedge may work out of its place, no matter how well the halts may be tightened.
Our correspondent tells us that he has applied this method with excellent results to more than one motor coach that, formerly, would hardly hold the road at speed.