MOTOR NOTES

Dominion, Volume 9, Issue 2606, 30 October 1915, Page 13

MOTOR NOTES

IB? CIiUTOH.]

Caro of the Car. In tho' change from cold to hoi) weather certain conditions are brought about in an automobilo which call for alteration in treatment if the best services is to bo secured. Thicker oil can bo used with advantage when tho temperature'is such that there is no danger of it failing to reach the bearings. This is especially desirable if the cylinders and pistons are inclined to leak gas. It is a bad plan to run the jengine idle in hot weather, as it overheats more quickly than under ordinary conditions. In coasting the engine can be cooled a great deal by cutting off the ignition and opening the throttle, thus allowing the cool vapour to enter the cylinders. The better plan, however, is to have an extra air inlet on the induction pipe, which can be opened tb enable tho cool air to rush through tho cylinders without wasting petrol or causing explosions in the silencer when the spark is switched on again. The high gear should be used as much as possible, and when country touring tho cut-out may be opened to allow the hot exhaust gases a quicker passage to the open air. In hot weather more air can bo mixed with tho petrol. This will savo fuel and lessen the chalices of tho engine overheating. Touching up Bodywork. The repainting and varnishing of a car body is work that is quite' outside the range of the average amateur's experience and skill, and in ca-ses where a properly-finished body is required, there should be no hsitatiou in having tho work done at the coachbuilders. It would bo time, money, and labour lost to try to approach the class of work done by the skilled craftsman. At tho same time, it is often tho case that a car body is not worth having so much time and money spent on it, although it would be worth while to endeavour to iniprovo the time and weather-worn appearance. It is quite practicable to do this.if somo time and caro bo given to the operation. Exporiencc, however, is the only guide as to tho best way to carry out the details of the operation, and the most that an articlo on tho subject can do is to convey sQme general hints. Instead . of going through the routine of painting and varnishing, it is much simpler to uso one or other of tho several enamels which aro sold for tho purpose. Tho enamol of tho desired colour havo been obtained, it can be applied directly to tile 6urfaco of the body. The preparation of the surface is, however, very important, as the final result will largely depend upon this. What has to bo aimed at is the production, of a perfectly even surface, thoroughly free from grease, and preferably not too smooth, so as to givo the enamel a better hold. This docs not imply that the surface to work upon should bo coarse, but such a surfaco as can bo worked up with moderately-fine glass paper or powdered pumico stone. Care should be taken to work right into tho corners and parts of the surface that aro rather difficult to reach. Particular care must be taken that tho actual enamelling is done in a thoroughly dustless room, or if it has to be douo out of doors, some sort, of . a screen should bo devised that will prevent any dust or fluff being blown on to tho enamelled surfaoc, either during the operation or tho period when tho surface has to bo allowed to "sot," and this lis usually a matter of several days. The selection of suitablo brushes is a point of importance. Cheap brushes are a delusion, as the bristles come out and adhero to tho surface and spoil tho work. Proper enamel brushes are made of just the right shape and stiff. ness for Shq .wnrkv •

Thin coats of enamel should, be the rigid rule. .Heavy coats. will "run" and show streaks and ridges in a most objectionable manner, and no amount of rubbing down afterwards will bring the surface right. TJio only treatment is to wash the enamel off with a solvent, usually turpentine, and start again. At least three coats of enamel should be given, each coat being allowed thoroughly to set, afterwards being rubbed down with fine glass-paper or pi'mice stone. Tho thinner the coating, obviously the less time that will be taken for it to set. The application of tho final coat should; he dona with special care, so that something like a presentable surface may be obtained. Practical experience is the only useful guide to the best way to manipulate tho brush, so as to avoid leaving marks. It may be stated, however, that a very light touch is-neces-sary, and tho brush should be nearly, dry. A plan that the writer has adopted with considerable success to produce a. better finish that the brush finally leaves is to go over it, when it is properly set, with a pad consisting of a ball of cotton wool enclosed in a. piece of linen. This pad is made damp with turpentine, and rubbed very_ lightly over the surface in various directions. This:: treatment takes out brush marks, provided these are not heavy ones. When the surface is finished it is very, important to allow it to become hard; in fact, it is all the better if it, can be loft for a couple of weeks or< so i before it is touched, as it is very disappcintins; to find one's work badly marked' from contact with the hands.—: Sydney "Sun."