Innovation Ideas

Yeah....

It's called a combi drill.
Bosch ones are called GSB. The impact is really handy, but if it is something you use more than 50% of the time then its best to have a drill driver (a GSR) and an impact (GDR)

This is the one I am 'hoping' santa brings me ;)
www.bosch-professional.com/gb/en/ocs/tools/101307/24679/cordless-combis/gsb-18-ve-2-li/

Hi Gareth,

There seems to be some confusion here so we'll try to clarify matters.

The first ambiguity may be in the use of the term ‘Impact Drill’.  Unless we are mistaken, you are referring to an Impact Driver, which is as you say ‘completely different’ to a ‘combi’ which is purely a cordless drill/driver with an impact drilling function added.

An Impact Driver does indeed apply blows to the head of the screw but not as you may think, and certainly not in the same way that an impact drill (combi) applies impacts to a masonry drill bit.

An Impact Driver applies ‘Radial Impacts’ or ‘Turning Blows’ if you like, which applies torque (or turning power) to the screw or bolt in a series of blows, in the same way that someone who, for example can’t quite loosen a stubborn bolt with a hand held spanner and so might resort to hitting the end of the spanner in the loosening direction to ‘shock’ the bolt into turning.

Impact drivers (normally cordless) are increasingly popular these days, and in some countries are actually outselling the more conventional 2-speed drill/drivers.

They are quite versatile, and with a standard ¼” hex tool holder can be used not only with screw-driving accessories, but with a wide range of drill bits too (e.g. Trend ‘Snappy’ kits etc)

It is perfectly in order to drill wood, or metal with these tools which will of course start to ‘impact’ when a certain resistance to turning is felt in the material – maybe 5Nm on the smaller tools.

In this respect you are right - they are noisy – but that is how they work.  They are very high geared (high RPM) and rely entirely on the ‘Impact Mechanism’ to deliver any real torque.

The only exception is when, for example, drilling small pilot holes (say 3mm) in soft wood when they will not impact, just drill really quickly.

So now to your original question:

Generally speaking conventional impact drivers have no facility to switch off the Impact Function since it is critical to the normal operation of these tools.

If you were able to switch off (or disable) the mechanism, you would simply be left with an ultra high speed drill with very little usable torque, that would stall with anything more than the smallest drill bit fitted!

However the good news is, that there are so called ‘Multi-Function’ Impact Drivers available from the Bosch Professional Cordless range, and to be fair other manufacturers too.

Ours are called the GDR14,4V-LI MF, and the GDR18V-LI MF with 14.4V & 18V Lithium Ion batteries respectively.

These tools are a little chunkier in appearance but otherwise similar to the standard Impact Drivers around at the moment.

The difference is that they have three modes:

1st gear slow rotary only drilling and screw driving (No Impact – no noise)
2nd gear fast rotary only drilling and screw driving (no Impact – no noise)
2nd gear with Radial Impact (and noise) for high torque applications i.e. the usual stuff – big screws, bolts etc.

Could these be the tools you are interested in?

Check them out on our website

Thanks for your interest in Bosch Professional Power Tools and the Bob Forum

 Gareth, as Bob has explained there are "multifunction" Drill/Impact drivers available.  I have one, the GDR18V-Li MF, and have briefly used another, 4 mode Hammer Drill/Impact Driver from Makita.  The Makita was returned after a particularly frustrating day with it, as it was plain awful.

It's problems were manifold, with perhaps the worst being an adjustable clutch with less torque @ the most powerful setting than a flat 3.6v screwdriver, and an L-gated gearbox that stubbornly refused to switch gears and modes as it ought.

The other problems are in common with the Bosch version, such as a 1/4" hex chuck only, necessitating either hex shanked drills, or colleted twist drills from the likes of Trend.  Above about 1/8" in size, any torque applied to the workpiece would result in the smooth shank of the drill spinning in the collet, irrespective of how forcibly it was tightened.

It is certainly a very versatile drill/driver, nevertheless, and can be easily and speedily be adapted from drilling with spade bits to driving.  It's also excellent for using sockets to tighten the nuts of Dynabolts. Low gear is about 750rpm, and top the same as the impact setting, 2600rpm.

It is, however, fairly big in the head.  Much bigger than a dedicated "rattler".  It, in common with many others, doesn't have adjustable torque, or even speed/torque as do better tools from Makita, for example. But perhaps it's worst crime is that it doesn't have a safety clutch (for the tool, not the operator).  It can be too easily be stalled out in either low or high gear.  Stalling this tool results in armature smoking and burning smells, and if repeated is guaranteed to lead to its early demise.  As a result I can only ever drill in "rattler" mode, to prevent stalling, which rather defeats its so-called "multifunction" purpose, don't you think?

Just use you current rattler with some el-cheapo hex shank bits, and the occasional spade bit!