The Equipment and Organisation of a Motor Repair Shop or Running Shed.
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FIFTH ARTICLE.
In continuation of this series, the first of which appeared in our issue of August 24th, we now illustrate and describe four drilling machines suitable for use when doing the larger work to be found in most running shops. The tools which we have shown in these pages are only a few of the many types to be obtained from machine manufacturers and dealers. Therefore, to touch upon the subject as broadly as
possible, we shall subsequently give a few examples of the radial type of drilling machine.
Messrs. Lee and Ilunt, of Arkwright Works, Crocus Street, Nottingham, make a very handy machine for general work and capable of drilling holes to gin. in diameter. It will admit of work 2f 1. in diameter being operated upon, as the distance between the spindle and the pillar is r2in. The pillar is cast in one piece with the head, the whole being bolted to a heavy base-plate. A steel spindle, which is I lin. in diameter, revolves in adjustable conical phosphor-bronze bearings. Both self-acting and hand feeds are fitted to the machine; the former is worked off a horizontal shaft, which operates on the hand-feed spindle, by means of a worm and pinion drive. The arm, which holds both the table and a parallel vice, is raised and lowered by a rack and pinion motion. The whole arm can be swung round the pillar when it is desired to bring the vice underneath the spindle. The baseplate is planed, fitted with .1. slots, and has a circular hole to carry rho lower end of a boring bar. The principal dimensions of the machine are as follow : Approximate weight, complete, tocwt.; size of the bed-plate, 3oin. by 18in.; vertical feed of the steel spindle, 6in. ; maximum adjustment of table, 23in. The inclusive price of the tool is ,3o. The workmanship and design are good, all handles being conveniently placed for easy manipulation.
Alfred Herbert, Limited, of Coventry, sells an excellent machine which will drid holes up to imn in diameter. As will be seen from the illustration, the design is simple, whilst the general construction is massive. The work-table, which is carried on a neat swivelling bracket, is totin. in diameter. It is provided with 1,-slots for bolting down purposes, and is raised and lowered for different sized work by a vertical screw operating in conjunction with two bevel gears. The spindle is of a special type of hammered steel, fitted with a quick return motion. The driving bevel gear wheels have teeth of a coarse pitch, and these are cut from the solid. A useful feature is the automatic stop, which allows of the machine's being set to drill to a predetermined depth, at which point the feeding motion ceases. The base-plate has slots on its upper face to enable any large work to be bolted down to it when necessary. The total height of the tool is sft. 7in., whilst the diameter of the pillar is sin. A maximum vertical space of nin. is provided between the bottom of the spindle and the work-table, and the distance between the spindle and the pillar is tolin. The makers recommend a speed of about 400 revolutions per minute as being most suitable for the lower driving shaft. An automatic arrangement can be supplied for use when tapping holes, which have been previously drilled on the machine. The price of the complete tool is .4.21.
The T3ritannia Engineering Company, Limited, of Colchester, makes various types of drilling machines very suit able for the different kinds of repairs usually found to crop up in a running shed. We show on this page an example of a particular type of machine which has been supplied in numbers to the order of the British Government. The main body of the tool consists of a heavy casting, which is made in one piece with the turned pillar, and the whole is bolted to a substantial foundation plate. The latter is provided with the usual slots for bolting down work. The steel spindle runs in gun-metal bearings, which are adjustable for wear, and can be easily renewed if this should be necessary at any time. The bevel driving gears are cast steel, and are cut from the solid. A reversing motion is fitted to the spindle; this consists of a clutch which is actuated by a handle conveniently placed within the reach of the operator. The cone-driving pulley has three steps, the largest of which has a diameter of oin., and the company recommends a normal speed of 140 revolutions per minute. The machine has both hand and self acting variable feeds, the latter being obtained from a horizontal shaft having a worm, at the inner end, which meshes with a worm wheel at the lower end of the hand-feed shaft. Ihe double arm has a parallel vice at one end, whilst the other carries a slotted work-table. The arm is elevated or depressed by means of a rack and pinion. Sonic of the principal dimensions are as follow :----Steel spindle, ifin. in diameter; maximum depth of hole drilled, 7in.; diameter of hole drilled, iiin.; diameter of work-table, 2oin.; distance between pillar and spindle, 12in. ; diameter of pillar, Gin.; total height, 61t. Gin.; approximate weight, r3cwt. The price of the machine is 435. Cast-iron gear covers can be fitted to enclose all the exposed gearing, to conform to the requirements of the Factory Acts.
Brown Brothers, Limited, of 22-30, Great Eastern Street, London, F..C., sellsa drilling machine which can be fitted for either hand or steam power as desired. Our illustration shows the hand-driven tool which will drill holes up to iiin.
in diameter. The head, which is a strong casting, is bolted to the pillar. Two speeds are fitted, either of which can be brought into operation by moving a small lever. The drive is by bevel gearing, which is cut from the solid, and has coarse-pitched teeth. A self-acting feed is fitted, and the spindle can be quickly brought down to the work by a hand wheel on the left-hand side of the head. The arm has both vertical and horizontal motions, and it can be rapidly brought into any position. The usual work-table is dispensed with, its place being taken by a vice-plate, the two halves of which can be brought simultaneously together by a screw having right and left threads. Some of the dimensions are as follow :—Distance from pillar to spindle, 13in. ; diameter of vice-plate, 15in.; total height, 7ft. am,; approximate weight.
Sicwt. The inclusive price for the hand-driven machine is
• -417 125., and with overhead motion for power £22 4s. The Tangye Tool and Electrical Co., Ltd., of Birmingham, makes various forms of radial drilling machines, very suitable for the uses of the heavier class of repair work, in the machine to be illustrated, the radial arm does not move vertically, but it can be swung completely round the column, so as to be well out of the way when setting up work. The machine can be worked through bevel gearing only for light work whilst for heavy jobs the double spur and bevel drive can be brought into operation. The spindle is of steel, and the end thrust is taken by ball bearings. The feed motion is self-acting; it has three speeds, and is operated by a strap running over stepped pulleys. The saddle is moved along the arm by means of a rack and pinion worked from a conyeniently-Placed handle. The base has j slots on the top and on one side for bolting down work. The spindle is 24in. in diameter, and has a vertical movement of r4in. A speed of 25o revolutions per minute is recommended for the countershaft. The maximum working radius is 4ft., whilst the weight complete is about 54cwt. The tool is sold at
For certain jobs where it is necessary to drill to the centre of work of large diameter, radial drilling machines are superior to the ordinary type. They are necessary for long work of awkward shape, and the fact of the table's being slotted on the side, as well as the top, makes them most useful for many purposes out of the ordinary run.