11 May 2022
It’s time to talk the torque
So that’s why we would like to take you through a typical drill/driver’s controls and show you what each one does, and why – and when it should be employed. Here goes…
Power tool selection – some factors to consider
Here are a few factors you might like to consider when selecting any power tool, be it electric-powered cordless or mains supply, or pneumatic or petrol-powered…
- How often will you be using it, and for what?
- How heavy is it?
- What is its power, torque and other ratings and speed?
- Is it an established brand?
- Is it a generic brand?
- Does it come complete, or are there other items you will need to purchase… battery, power cord and so on?
- Is it the right ‘fit’ for your hand/s?
- What warranty/guarantee does it have?
- Does the brand have a well-established parts/repairs back-up facility?
- What comments/ratings can you find regarding the tool?
- What accessories are available for use with the tool?
Apropos the list, you might have other considerations as well, but to explain some of the above a little…
- Regarding weight, handle size and handling, you need to know you can handle and control it properly – control is vital! A power tool you cannot control properly can be positively dangerous and cause severe even life-threatening injuries.
- It needs to be powerful enough to do the work for which you are buying it.
- Mica stores stock top established brands but do not necessarily right off new brands… after all, even the big names of today had to start somewhere.
- If you also have to buy batteries or whatever, that is not a problem, but you just need to ensure that you know what toe final total cost will be.
- If you confirm that there is a good spares and repairs back-up, you know that you will be able to have the tool repaired should anything go wrong.
- The longer the warranty/guarantee, generally the better – but note that if the tool is not used according to the manufacturer’s guidelines and suffers damage as a result, the cost of replacement/repair is very likely to come out of your own pocket.
- Knowing what accessories are available will allow you to make a better estimation of exactly what you can use the tool for and in what situations.
- And finally, find out what other people say about the tool and/or brand – but decide only after you have checked out multiple sources… remember, bad workmen often blame their tools for a bad job and that can colour their opinions. By the same token someone who has had a great experience with a particular brand might sing its praises. In either case – pro or con, there can be a tendency on the part of some individuals to exaggerate – so drawing from multiple sources will assist you in making a rational, informed decision.
Tool development is on-going, so even within the same brand and the same range of tools, specifications can and do change from time to time. Hence it is always a good idea to know EXACTLY what your tool’s capability is and ensure that you do not use it in a manner that might overload or even damage the motor and/or gearing. For instance, if it is rated to drive in screws up to 6 x 75mm, do not use it to drive 8 x 75mm, or 6 x 100mm.
Think of it terms of towing a caravan – you would not use a small 1100cc car to tow a 6-birth twin axle caravan with a GMV of a couple of tons… as much as you would like to!
First of all, as we all know, tools, whether mains or cordless, as featured here, are available in a range of sizes, power ratings, drilling capacities and so on.
In the case of this tool, its operating specifications are as follows
- Masonry – 13mm
- Steel – 13mm
- Wood – 38mm
- Wood screw – 6x75mm
- Machine screw – M6
- Low  – 0-500rpm
- High  – 0-1900rpm
Hammer action (blows/minute)
- Low  – 0-7500
- High  – 0-28500
The instructions that accompany the tool go into more detail, but the above is the gist of what you need to know; having said that, ALWAYS read and understand the instructions before using any tool – be that a powered type… electric (mains or cordless), pneumatic, petrol – or even a hand tool such as a pop riveter.
If you misuse/abuse any tool you will very likely void any warranty or guarantee and be out of pocket.
Right, let’s take a look at the tool’s controls and what they do… and when…
- This is a compact and versatile tool – cordless tools while not having the power of their mains-powered counterparts – allow the user to complete just about any task (within the tool’s capabilities) during any blackout.
- The switch trigger is your on-off speed-control switch, as it is electronic this means you can adjust the speed by increasing or decreasing the amount of pressure you are applying to it.
- This is the reverse switch lever, which as the name suggests, changes the direction of rotation of the tool’s chuck. With it depressed on the left-hand side of the body as shown here, the rotation is counter-clockwise – for removing screws, for instance. (Note the directional arrow indented on the button.)
- In this position, it is pushed in from the right-hand side of the body and the rotation is clockwise – for driving in screws, drilling and so on. (Note the directional arrow indented on the button.)
Note 1: When the switch is in the central neutral position, the trigger switch cannot be pulled.
Note 2: We have all done it – we’ve tried drilling a hole only to find that the drill bit simply will not drill the hole. Before rushing off to your local Mica and complaining bitterly about the blunt bit you just bought… check that you are not running the tool in reverse.
- This is the speed control. With the switch set to , the no-load speed of rotation is 0-900rpm. You would usually select the low range for driving in screws, for example – or when drilling very carefully to avoid drilling too deep.
Note: The use of the term ‘no load’ mean that the drill is not in contact with any material and ‘doing work’… it is simply spinning away happily.
- With the speed control set to , the operating no-load speed range is 0-1900rpm and this is usually the setting you would select for drilling and other tasks where you require high speed.
- Just what you need during a blackout… when the trigger switch is pulled, the light goes on and illuminated the immediate work area around the tip of the drill bit or whatever.
- This is the hammer/screw/drill selector… here it is set to the hammer function, which gives you a percussion rate of Low  – 0-7500 blows per minute and High  – 0-28500 blows per minute. You would use this function when drilling into masonry or brick; the drill bit reciprocates rapidly back and forth and this helps the masonry drill bit penetrate the brick or masonry far quicker than it otherwise would.
Note: Use this action only when drilling through masonry or bricks, NOT through tiles or glass (they will shatter) or wood or any other material. When drilling through wall tiles, for instance, where possible drill where the grouting separates the tiles (easier to conceal should you ever wish to remove whatever you attached to the wall), and set the tool to drill until, the drill bit has penetrated the tile – then you can switch to hammer action to complete the hole.
- Here the screw function has been selected. It is best to set the speed selector to low  when driving in screws… drive them in too quickly and they might break, or the driver head will slip off the screw head and dive into the surface below, or you will strip the screw head.
- Here the selector has been set to drill and you can select Low  or High  speed as the situation demands.
- Now here’s the control selector that led to this feature’s title – the torque control. Think of it as you would your car’s clutch. When set to 1, as shown here you can easily hold the chuck stationary with the tool operating at any speed. You would lower setting when driving in screws through soft materials… when the friction acting on the screw’s thread meets or overcomes the rotational torque setting, the chuck and hence the screwdriver bit stops.
- Here the selector is set to 8, at which setting more force is being applied to the chuck and screwdriver bit, so the screw is driven in further before – as just mentioned above, the friction acting on the screw’s thread meets or overcomes the rotational torque setting, the chuck and hence the screwdriver bit stops.
- Here the torque control is set to maximum and is essentially in its non-slip position so while you might be able to hold the chuck still with your hand at the very lower end of the scale, at this setting do not try holding the chuck stationary – you will very likely get a friction burn.
- This shows the effect of the various torque settings, from 1 on the left to 21 on the right, and the other four screws at random, but increasingly higher settings from left to right. As you can see the screw on the far left, driven in on Setting 1, has hardly penetrated the wood, whereas that on the extreme right, driven in on Setting 21, has seen its head driven in below the surface.
Knowing how to use your drill/driver’s torque setting correctly will be a boon to you in all sorts of situations – for instance when you have to drive in a series of screws to the same depth – for example when attaching a backing to a frame, when you would want the screw heads to all be uniformly flush with the outer surface of the backing sheet.
Get hold of a spare piece of the backing and a representative piece the frame timber (i.e. a piece that best represents the grain and hardness of the frame timber) and drive a number of screws into it, adjusting the torque setting until you have the right mark. Now you can drive all the screws in without the risk of driving the screw heads right through the backing and hence not securing it to its frame.
Having said that, always take care when doing a job such as this … if the screw is driven into an area of softer frame timber, the screw head will probably not end up flush with the backing’s surface, but driven right through it into the frame itself.
Mica Stores carry a range of power tools. To find your closest Mica and whether or not they stock the items required, please go to www.mica.co.za, find your store and call them. If your local Mica does not stock exactly what you need they will be able to order it for you or suggest an alternative product or a reputable source.