SDS drill terminology . . and a view on a model

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robgul

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I need an SDS drill for some concrete work (almost a one-off) but the time I need it for makes hiring expensive - by the time I've hired the drill and bought the bits it look like a value judgement on buying a budget model.

First : Screwfix has various SDS drills and refers to "n Kg" in the spec - what does that mean?

... and Tool Station has the Bauker 1500W 32mm SDS Plus Rotary Hammer Drill 240V for about £70 with bits etc - reviews on the site largely positive, any experiences here please - or other suggestions near that price point?
 
One Newton is the force required to accelerate 1 kilogram of mass . ( OK i giggled it :LOL:)

Yep, I found that . . . is the kg figure just the degree of "oomph" that the drill has? - although I was assuming the motor wattage was also a factor ?
 
I think its impact force at the pointy end, the bigger the motor wattage the more Newtons it can produce :unsure:
 
I have the Screwfix Erbaur one, it’s been brilliant. Like you I don’t use it all that often but every time I use it I’m extremely impressed, concrete lintels – like a knife through butter, I bought a tile lifter, - spade shaped attachment for it and that is really useful. Ian
Edit, mine came with a Jacobs chuck as well in the case.
 
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N is Newtons, not sure what n kg is, or do you mean “n” is a number? In which case it’s the hammer weight.

The bigger your hammer, the harder you can hit (duh!), but you have more mass to lift.

Depending on what concrete work you have to do, you may need a big one, generally you don’t and it just takes longer with a small one.

Having hammer only is fantastic as you can use cold chisels for breaking out old fence posts etc... it’s a very sound investment of not much cash.

A normal jacobs chuck (that’s one that talks about sharpening a lot) is useful to use your ordinary bits, but you can buy an adapter later on or get auger bits that fit an SDS/SDS plus for when you want to really drill big holes.

Aidan
 
When drilling concrete, a direct interpretation of drill wattage gives an incomplete picture: The drill has to impact the concrete first with enough force to break the material and then remove the fragments before the next impact can be exerted. Most hand drills with a "hammer" function that relies on a toothed cogwheel that provides very short strokes at a high rate or "BPM" (Blows pero minute), is only adequate for drilling holes in not too-hard materials, like brick or masonry. On the contrary, the bigger "Rotary Hammers" that use a pneumatically actuated piston driven by the electric motor, can deliver less blows per minute of a much higher force and effectivity. Thus, Wattage alone cannot describe the effective drilling "power" of a given drill, but the "Joules" rating is much more directly related to drilling speed and easy. At least in my country, good rotary hammers are expensive for an ocassional use, except perhaps the Skil-1859 model, which is about half the price of the next more powerful model from other brands like DeWalt or Bosch. It has a 2.1 Joule rating, and can make up to one inch holes in hard concrete. Its motor is perhaps a bit too low on copper, therefore it tends to overheat soon when pushed hard, but for th price, it seems a good value for the money as it comes with an SDS-Plus chuck and an adapter for a std chuck and three concrete drill bits, a pick and a chisel. Taking care of letting it cool between holes, it could be a very good value. Best luck.
 
N is Newtons, not sure what n kg is, or do you mean “n” is a number? In which case it’s the hammer weight.

The bigger your hammer, the harder you can hit (duh!), but you have more mass to lift.

Depending on what concrete work you have to do, you may need a big one, generally you don’t and it just takes longer with a small one.

Having hammer only is fantastic as you can use cold chisels for breaking out old fence posts etc... it’s a very sound investment of not much cash.

A normal jacobs chuck (that’s one that talks about sharpening a lot) is useful to use your ordinary bits, but you can buy an adapter later on or get auger bits that fit an SDS/SDS plus for when you want to really drill big holes.

Aidan

Yes "n" was for number in my original post.
 
Hi

You are not saying whether you want to drill holes or break concrete up, so is it a drill only or do you also need a breaker, one where you can turn off rotation?
 
Hi

You are not saying whether you want to drill holes or break concrete up, so is it a drill only or do you also need a breaker, one where you can turn off rotation?
Sorry - for the moment it's just for drilling into concrete bases and lintels/fence posts as well as through the odd wall for electrical conduit. . . . . breaking stuff may come later but that's often better with an electric Kango!
 
I gave a titan sds Max which is more of a beaker.

Also I have the a DeWalt sds which is more of a general purpose drill. Cost about £60.

Cheers James
 
The spec for the Bauker at Tool Station is:
FEATURE

3 functions: rotary drill, hammer drill, chisel
Aluminum gear box
Rubber over mould grip
Forward and reverse rotation (A couple of the reviews do suggest there is no reverse . . . can't see why you'd need it with a machine just for drilling holes/breaking stuff?)
Quick change SDS-Plus chuck

SPECIFICATIONS

Rated power: 1500W
No load speed: 850/min
Impact rate: 4200/min
Max. impact energy: 5.5J
Max. drilling capacity:
32mm/concrete , 13mm/metal, 40mm/wood

That seems pretty powerful based on the wattage/power and Joules.
 
Looking at the technical spec for that range of drills, there doesn't seem to be any detail as to the weight of any of their drills......
This surprised me a little as it is relevant if you are going to be using it for any period of time.
The 1500w version you mentioned is a fairly big, hefty machine and depending on what you're planning on drilling and how often you're going to be using it, you may choose to go for the slightly smaller version as it will certainly be easier on the arms and wrists.

A 1000w SDS drill would be far better suited to drilling holes with the occasional bit of chiselling.

The 1500w version would be more suitable for breaking up concrete or chiselling up floor tiles for example as all the weight would be downwards and be of benefit.

I have both types of these drills ( different brand) and the decision to use one or the other depends on the job at hand.
 
Just a thought as I mainly use my sds out side where being cordless is a big bonus, if you have a battery platform of one brand or other for any cordless tools you have could you buy a bare drill for that platform. This is what I did with my Makita & it was just over a £100
 
I got myself the cheapo Screwfix (Titan?) one a few years back. Happy.

I was breaking up fence post holes which the builders must have put in 30 years ago expecting heavy bombers. Spent 2 hours with sledge, lump and various cold chisels on one, drove off to Screwfix, bought the cheapest SDS they had and did the rest at about 10 minutes each. Never used one before, thought is wasn't working properly until I put some pressure on it then - rattle rattle whoosh - yes it does.

Paid for itself that afternoon. Not a 'nicely made proud to own' kind of tool but effective. Chisels not that good but a quick regrind helped. They are never going to be sharp but a bit pointy helps. Lots of stuff in the box including a Jacobs chick and drill bits, most of which I've never used. Its one of those tools that does what it does but is a bit heavy and awkward if you have an alternative. It's esential to have the non-spinny hammer option for breaking stuff up - I suspect all of them do.

Downside - it's addictive - after the fence posts came a wholly unnecessary smashing up of a bit of patio I didn't like, a most enjoyable hole in wall for a kitchen extractor, and an offer to a neighbour (which he didn't accept, sadly) to make a hole in his garage wall when he locked himself out.
 

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