Question re powerful hammer drills...

[Rob K]

Hi

I've had some trouble drilling into my walls using an 850watt Bosch Hammer Drill with brand new high quality masonry bits. Its a pretty hefty thing and makes a lot of noise when hammering but not a lot of depth to show for it. I thought I'd hit some steel or something else impenetrable. They're only 6mm holes (for some shelving units) but I couldn't drill more than 10-15mm depth.

I recently had some new windows fitted and asked one of the guys if he could have a go and see if he could finish off the holes I started. His drill went into my walls like a hot knife through butter! His drill was much smaller than mine, ran on 110v from a stepdown transformer and used SDS bits. He said it was to do with the hammer action - maybe it was pneumatic?

Is this correct? Is it possible to get an electric drill with a pneumatic hammer action?

Any idea why his smaller drill was so much more effective? Was it the SDS bits? Was it the length of the bits?

I'm baffled.

Thanks

Rob

[TonyK]

Just go buy a cheap SDS drill for £40 from Argos and it will sort the problem. For more info Google the group on "SDS" and you'll find this has cropped up maybe 10 times a month for the past ? years.

[Tony Bryer]

SDS. When it comes to hard brick and concrete it's way better than a traditional hammer drill ... as you've seen for yourself.

[Set Square]

It was the combination of SDS bits and an SDS drill - you can't use SDS bits in an ordinary hammer drill.

SDS provides a much more effective pneumatic-drill type hammering action.

[Bob Minchin]

I thought that SDS referred to the method of holding the drill bit in the drill rather than the method used to achieve the hammer action.

If this is that case, can one be assured that a cheap SDS drilling machine will automatically have the increased drilling effectiveness associated with professional SDS equipped drills?

Bob

[Dave Plowman (News)]

Not only possible but the solution. SDS drills go through concrete etc that a hammer drill won't touch like the proverbial knife through butter. You wouldn't believe it until you try one.

[John Rumm]

Its the the whole bundle really. If you buy a SDS drill then you get the enhanced hammer action to go with it. This in turn requires the use of the SDS bits.

Yes. It will certainly be (much much) better than a conventional hammer drill. The "pro" versions add more refinement to the product, like longer life, better speed controllers, safety chuck etc. Many also have a "rotation stop" or "chisel mode" for using the hammer action on its own.

[Dave]

Hi Rob

Big difference between percussion drills and rotary hammer drills.

SDS is the generic name for a chuck & bit system originally designed by Bosch. The letters stad for the German words Insert, Twist, Lock or something. It allows the chuck to turn the bit, but also allows the bit to slide in and out by about an inch.

A percussion drill basically works by making the bit vibrate as it spins. A rotary hammer drill whacks the back of the SDS bit as it spins.

If you buy a rotary hammer drill it can also ne used as a mini breaker by turning off the rotary action (most models). The sharp end of the SDS bit is much the same as others.

Dave

[SmileyFace]

Wot he ^^ said.

Gill

[Dave Plowman (News)]

I kept the post below as the question comes up so frequently:-

From: Paul Scott Subject: Re: What is "SBS"? Date: Thu, 26 Sep 2002 09:45 Newsgroups: uk.d-i-y

"SDS originally stood for the german Steck - Dreh- Sitzt (insert - twist - stay)and simply refers to the patented Bosch "keyless chuck" system, whereby drill bits (and saw blades in jigsaws) can be replaced without the need for an allen key. Today SDS stands for Special Direct System or in german Spannung Durch System."

[John Rumm]

As most other makers would say, "tool free blade changing".

SDS blades have a little bulge on each side fo the blade about 10mm from the top of the blunt end, this is what the SDS blade holders hang onto. You can use a SDS blade in an ordinary jigsaw, but not vice versa.

[Jan Wysocki]

Aha, at last I understand why my Bosch jigsaw calls itself an SDS-. Thanks.