more power to your elbow . time saved is money saved , they say ; and when holes have to be bored an electric drill will certainly save one heck of a lot of time . but there is much more to it than just that , for in the past few years these compact power tools have been developed to a stage where they can tackle almost any job you care to name . grinding , paint mixing , precision turning or polishing floors - it &apos;s a fair bet that there &apos;s a drill accessory designed for the purpose . nowhere is a power drill more useful than in the garage , where it can form the basis of a comprehensive workshop and so provide near professional facilities for maintenance and repair work . but however ingenious an attachment may be , it can only be as good as its power unit . so , before whaling in to your bank account , have a good look around , comparing specifications and prices and ensuring that the drill you fancy will drive the attachments in which you may be interested . all the popular makes of drill , produced to exacting standards , offer a high degree of reliability and an efficient after-sales service . on what , then , does choice depend ? well , on weight , for one thing ; or on style . one maker discovered that eye-appeal increased his sales and so you might fall for a charming pastel shade ! then , too , there are practical features to be considered , such as an automatic cut-out , or double insulation which does away with the need for earthing . the price ? anything from about &amp;pound;7 upwards for the drill itself - and , unless you hold yourself in check , up to ten times that amount for accessories ! but many of the manufacturers have taken the sting out of the cash side by operating their own hire-purchase schemes . a buyers &apos; guide to drills suitable for the do-it-yourself enthusiast is appended , and somewhere in that list is a power tool to meet your needs . but when buying , check that the operating voltage ( marked on a plate on the drill body ) is suited to your mains supply . it is also a good idea to spin the chuck by hand , to ensure that the spindle is free-running and has survived the trip from factory to dealer without damage . you will want to try it out as soon as you arrive home , but curb your impatience for a while . check , first , that the plug is properly connected . if the green-covered cable runs to the earth pin , red to the pin marked L and black to the pin marked N , then everything is as it should be . once you have bought your drill , then it is only common sense to look after it properly , and simple maintenance will keep it in good order almost indefinitely . say the power-drill makers , 75 per cent of major breakdowns can be traced to neglect of the carbon-brush gear . so it pays to carry out regular inspection of the brushes , replacing them , in the grade and size recommended by the maker , when they have worn to a third of their original length . as with motor-cycle dynamo brushes , care should be taken to see that they bed down properly on the commutator , with the spring pressure sufficient to keep the brushes in close contact . ventilation holes in the drill body must be kept free from dust , screws should be checked for tightness regularly , and - an obvious point , maybe - cable leads must be inspected from time to time for signs of fraying or of faulty connections . go steady on greasing and work strictly to the instruction book , for too much grease can bring a train of trouble . it could cause the motor to overheat . overgreasing the rear bearing could foul the commutator . and if there is too much in the gear box a stream of surplus might be blown into your face ! if your garage is damp , play safe and keep the drill in the house when not in use , for damp is one of the worst enemies of an electric motor . and when storing the drill , coil the cable neatly without kinks or sharp bends . when removing the chuck or setting up the tool for a specific job , always follow the maker &apos;s recommendation . never push a screwdriver or other tool into the body of the drill in order to jam the shaft . you can n&apos;t see what damage you may be causing , nor will it show until the current is switched on . and should the drill give trouble send it back to the manufacturer &apos;s service depot , for do-it-yourself repairs are ticklish unless you are a skilled electrician . factories place great emphasis on accident prevention , and it is equally important that safety habits should be developed in the home workshop . wear overalls , for a start , so that there is no loose clothing to be caught up in moving parts ( ties and shirt-sleeves , for example , are particularly vulnerable ) . and it is as well to wear goggles - your motor-cycle goggles will serve admirably - when pieces of metal are likely to be flying about . petrol , or any other inflammable liquid , should be removed from the working area , for a spark from a grinding or sanding wheel can start a fire . a good tip is to disconnect the tool when setting up an accessory , or making any other change . also , if your drill has a locking button incorporated in the switch , it must be released . incidentally , if the drill cable is plugged into a switched socket , in case of emergency the simplest thing is to flick off the switch ; if something has gone wrong with the drill you will n&apos;t want to fumble around trying to release the locking button ! finally , never , never pull a drill around by its power lead . it is so easy to pull a connection loose - and you will n&apos;t find out about it until you pick up the drill and try to switch on . having bought your drill , how do you set about using it ? and which of those alluring attachments are most useful for the motor-cyclist &apos;s workshop ? well , we &apos;ll go into the practical side of things next week . not such a boring job &amp;hellip; ! from the display of attachments in a hardware shop window , you might well conclude that there is no longer such a tool as an electric drill , pure and simple ; instead , it has become a miniature machine-shop powerhouse . but for all that , the primary function of a power drill is - well , to drill ; and with its aid anyone can bore holes quickly and easily . but there are holes and holes , and to make a proper job of things , while at the same time prolonging the life of the drill bit , it is worth while taking a little trouble . so , for a start , we can ignore those cheap ( and usually foreign ) sets of twist drills on the chain-store tool counters . almost certainly they are of carbon steel - good enough for a hand brace , maybe , but you would be lucky to use them more than once in a power tool . no , what you need are high-speed-steel drills , more expensive in first cost but cheaper in the long run ; these can tackle most jobbing work , but you will want yet another type of drill if there is glass , concrete or masonry to be drilled . a good high-speed drill will have the letters HS and the diameter stamped on the shank . but should there be no marking and you are in doubt , there is a simple way of identifying the material . touch the drill shank lightly against a grinding wheel and note the colour of the sparks . if red , then it is high-speed steel ; if yellow , carbon steel . now for the actual operation - and that should always begin by using a centre-punch to mark the job at the precise spot to be drilled . that acts as a guide for the drill point and stops it wandering from the required position . a comfortable working stance is essential , both to lessen physical strain and to achieve accuracy . that &apos;s where a bench drilling assembly scores heavily , a simple pillar fixture which converts the power tool into a bench drill . fixed to such a stand , the drill can be brought to the job with great precision , while pressure is increased easily by using the spring-loaded lever provided with the assembly . in addition , the stand baseplate offers a firm and smooth working surface . in some of the drill accessories available the bench stand also forms part of a lathe assembly , but Black and Decker market a self-contained bench conversion at &amp;pound;4 . when using a bench stand , it is advisable to interpose a block of wood between the baseplate and the job , so that when the drill point breaks through it enters the wood and not the plate . but whether the power drill is hand-held or used in a bench assembly , let your eyes and ears act as trouble detectors . listen to the drill &apos;s high-pitched whine , which will drop a tone or two as it bites into the job ; but should the note turn to a low growl too much pressure is being applied - so ease up a little , to obviate overloading and , possibly , burning out the motor . watch the swarf as it spins away from the drill flutes . with mild steel and other softish metals splinters and dust are a sign that more pressure is required , so increase it until good , fat shavings are twirling out from the job . they may be coming from one flute only , and if so the drill has been incorrectly ground . the drill point and cutting edges have also a tale to tell . if the point has blunted , then the pressure has been too great . if the outer corners of the cutting edges are wearing , or turning blue , the drill speed is too high . regrinding and setting a drill is really a job for an expert and beginners are advised to take them to a light engineering shop for the proper treatment . speed is an important factor in the life of a twist drill . the average domestic power tool operates at around 2,750 r.p.m , which although right for powering many of the attachments is a little too fast for drilling some materials . used at the right speed , drills will have a longer life and not require frequent regrinding . the basic rule is this : the harder the material and the larger the drill diameter , the slower should the speed be . though the simpler tools have no inbuilt method of changing speed , attachments are available which can step-up or reduce drilling speed to bring it into line with your needs . one , from Bridges at &amp;pound;2 4 s 10 d , gives a four-to-one speed reduction at the turn of a knob . another , by Black and Decker at &amp;pound;3 7 s 6 d , will not only double or halve the standard speed at will , but will also carry the drive at right angles for reaching awkward spots . as an instance , when a 1/4 in drill is used on cast iron , spindle speed should be about 750 r.p.m , and on brass , 3,100 r.p.m . makers of twist drills often issue tables of suitable speeds for various materials ; Intal ( Watery Street , Sheffield , 3 ) will supply a handy little booklet on the subject on request . where a drill speed may be quoted in peripheral feet per minute , do n&apos;t be alarmed . a simple formula &amp;formula; will give you spindle r.p.m . drill longevity and lubrication go together . some materials - wood , cast iron , brass and Bakelite among them - are drilled dry , but for most purposes a good all-round lubricant is soluble oil . one tip is to keep a supply in a polythene bottle with a small hole in the cap , and squirt it on to the drill as the job proceeds . in unskilled hands drills are easily broken . so for the inexperienced , stub drills - shorter than average and less likely to bend or break - are a good buy ( but be sure that they are long enough for the job you want to do ) . jamming is a common cause of drill breakage , and that is most often the case when a drill is breaking through at the far side of the work . 