What tool?

[Simon Avery]

Hello All

I have (waves arms) about 10m2 of concrete that's 2-4" thick. I need
to get rid of it so I can lay some decent paving without going about
the DPC of the house.

I was wondering, would a biggist cheap SDS drill do this? (I'm
thinking of the 2kg 40 quid Ferm jobbies in Screwfix). Even if that
takes a bit longer than a hired breaker I'd be happy as I'd have
another tool at the end of it, but would it actually do the job?

 

[Mike Taylor]

the easiest thing to break concrete at 2-3 inches is a sledge hammer. Once
you have the edge broken it goes very quickly. At 3-4 inches you may well
find that you need to hire a heavy breaker. Your SDS drill will not do it.
You may well buy a new one then use it and it may break to start with but I
am sure that by the end you will need a new SDS drill as it will have worn
out

 

[Grunff]

I have (waves arms) about 10m2 of concrete that's 2-4" thick. I need
to get rid of it so I can lay some decent paving without going about
the DPC of the house.

I was wondering, would a biggist cheap SDS drill do this? (I'm
thinking of the 2kg 40 quid Ferm jobbies in Screwfix). Even if that
takes a bit longer than a hired breaker I'd be happy as I'd have
another tool at the end of it, but would it actually do the job?

Don't bother with a cheapo SDS Simon, it'll die long before that
job is done. Yes it'll be under warranty, but that's another
trip to the shop etc.

As AndyM said, hire a kango for £20 - should make a very quick
job of it.

If you want an SDS, spend £100 on a DeWalt 566 - you won't
regret it. But I still wouldn't want to do that area with it,
takes too long.

 

[Dave Liquorice]

Wimp! Saw Charlie Dimmock breaking up a larger area than that on the
TV, using a sledge and a bar!

Quite. two people, one long crowbar and a sledge hammer. Once you have
got under an edge(*) just prise it up a few inches and whack it with
the sledge, at a point where it has no support underneath. Concrete is
excellent in compression but next to useless in tension, thats why you
have to put reenforcement into it for areas that are in tension.

(*) That might be the bit you need a power breaker for but a cold
chisel an lump hammer will do.

 

[Simon Avery]

Hello Grunff

G| Don't bother with a cheapo SDS Simon, it'll die long before
G| that job is done. Yes it'll be under warranty, but that's
G| another trip to the shop etc.

Yeah, and I've already got a few cheap tools that expired but I never
got around to taking 'em back.

G| As AndyM said, hire a kango for £20 - should make a very
G| quick job of it.

Gotya, and thanks for all the replies. I'll do that over a weekend
soon. (Got me little trailer to refurb first though)

G| If you want an SDS, spend £100 on a DeWalt 566 - you won't
G| regret it. But I still wouldn't want to do that area with
G| it, takes too long.

Understood. I don't really have a need at the moment for one, and the
bosche 20 quid normal drill I bought 7 years ago is still doing a good
enough job for me.

 

[geoff]

Quite. two people, one long crowbar and a sledge hammer. Once you have
got under an edge(*) just prise it up a few inches and whack it with
the sledge, at a point where it has no support underneath. Concrete is
excellent in compression but next to useless in tension, thats why you
have to put reenforcement into it for areas that are in tension.

Don't forget, it's much easier to break if you can undermine it (i.e.
remove whatever is underneath it)

 

[geoff]

Or a pickaxe, I reckon the more concentrated impact from a pick starts cracks
better, and you can alternate between thumping and levering.

But I agree with the others, this is a Kango job

Nah a sledgehammer

 

[Andrew McKay]

Don't forget, it's much easier to break if you can undermine it (i.e.
remove whatever is underneath it)

If you can get underneath it then one good way of breaking up the
concrete block is to light a fire underneath, then sit back and wait.

That's one of the methods that they used in days gone by to bring down
the walls of a fortress - dig a hole beneath the castle wall, fill it
with firewood, set it alight, then have a party whilst the castle
dwellers shat themselves knowing what was going to happen.

Andrew

Do you need a handyman service? Check out our
web site at http://www.handymac.co.uk

 

[Graeme]

Wimp! Saw Charlie Dimmock breaking up a larger area than that on the TV,
using a sledge and a bar!

Well, yeah, but surely the point is that Simon is really just looking
for an excuse to buy a new toy

Not that the rest of us would do any such thing <g>

 

[Guest]

If you can get underneath it then one good way of breaking up the
concrete block is to light a fire underneath, then sit back and wait.

That's one of the methods that they used in days gone by to bring down
the walls of a fortress - dig a hole beneath the castle wall, fill it
with firewood, set it alight, then have a party whilst the castle
dwellers shat themselves knowing what was going to happen.

You do need to have a large stone tower on top of it for this to work
though. The bit you missed out is that, as they dug under the defences, the
miners put in a large number of very heavy wooden supports, to stop the
tower falling down on top of them. The fire was to burn the wood away,
allowing the tower to fall under its own weight. Fred Dibnah demonstrated
this technique on TV, when he was demolishing a building. He also
demonstrated how difficult it is to know just when the timber is about to
give way and ended up running off the site as bits of masonry started to
fall.

Colin Bignell

 

[Andrew McKay]

You do need to have a large stone tower on top of it for this to work
though. The bit you missed out is that, as they dug under the defences, the
miners put in a large number of very heavy wooden supports, to stop the
tower falling down on top of them. The fire was to burn the wood away,
allowing the tower to fall under its own weight. Fred Dibnah demonstrated
this technique on TV, when he was demolishing a building. He also
demonstrated how difficult it is to know just when the timber is about to
give way and ended up running off the site as bits of masonry started to
fall.

You may be correct - but that's not entirely the way I understood it.

Yes, for sure you need to prop up the structure above. But the damage
to the concrete comes about because the concrete gets some localised
heat which it doesn't dissipate very well. And it can't expand and
contract like (for example) a piece of metal. And so it shatters.

However I'm happy to accept that I could be wrong.

Andrew

Do you need a handyman service? Check out our
web site at http://www.handymac.co.uk

 

[The Natural Philosopher]

Hello All

I have (waves arms) about 10m2 of concrete that's 2-4" thick. I need
to get rid of it so I can lay some decent paving without going about
the DPC of the house.

I was wondering, would a biggist cheap SDS drill do this? (I'm
thinking of the 2kg 40 quid Ferm jobbies in Screwfix). Even if that
takes a bit longer than a hired breaker I'd be happy as I'd have
another tool at the end of it, but would it actually do the job?

If I were you, I'd hire a self drive digger with piointy toothed bucket,
and smash it up and dig it up and put it in teh skip with that.

You can smash screed like that with a sledge, If its really concrete,
its a bit more of a bugger. But a 3tn digger smashing a toothed bucket
down on the lot is pretty hard to resist. Lilewise getting the bucket
under and edge and lifting..

If it's reinforced, all bets are off tho. Concrete saw is about the only
option.

 

[The Natural Philosopher]

Quite. two people, one long crowbar and a sledge hammer. Once you have
got under an edge(*) just prise it up a few inches and whack it with
the sledge, at a point where it has no support underneath. Concrete is
excellent in compression but next to useless in tension, thats why you
have to put reenforcement into it for areas that are in tension.

True, but use a digger. Then you won't have to carry all the bits into
the skip.

 

[mark]

sds is not the right tool for this job. Had to do similar area recently,
used a hired kango.
SDS with chisel bit ok for tidying up around the edges

As a few others have pointed out...a BFH is your best and cheapest
option. I smashed up about 20 square metres of contrete slabs on top
of about 6" of conrete & hardcore...the sledgehammer head weighs about
10kg....picture your mother in laws face on the concrete....BAM! A
nice bif crowbar helps too..

The hard bit was getting rid of the concrete...my local dump will only
take 5 bags of rubble...when i turned up there with two tons in a
trailer and another ton in the back of the truck.... Had to pay £10
per load at another "commercial" dump...still cheaper than a skip
though...

 

[Paul C. Dickie]

I have (waves arms) about 10m2 of concrete that's 2-4" thick. I need
to get rid of it so I can lay some decent paving without going about
the DPC of the house.

I was wondering, would a biggist cheap SDS drill do this? (I'm
thinking of the 2kg 40 quid Ferm jobbies in Screwfix). Even if that
takes a bit longer than a hired breaker I'd be happy as I'd have
another tool at the end of it, but would it actually do the job?

I'd doubt it, but you could drill lots of holes all over the concrete,
pack them all with timber and wait for rain...

On the other hand, you could ask your local scout troop to smash it up
for you with a few sledge hammers. That's the *best* way of saving
effort -- get someone else to do it!

 

[geoff]

Well, yeah, but surely the point is that Simon is really just looking
for an excuse to buy a new toy

Not that the rest of us would do any such thing <g>

Some of us need no reason

 

[Andrew McKay]

Bugger that - dynamite works much faster

Wasn't around in days of old when knights were bold. And paper was not
invented. They wiped their r's on a blade of grass, and walked away
contented.

I digress...

Not much time to sit back and have a drink while you're waiting though

Hell, there's always time to sit back and have a drink.

Andrew

Do you need a handyman service? Check out our
web site at http://www.handymac.co.uk

 

[Peter Ashby]

The castle in St. Andrews still has the mine and the three counter mines
the defenders dug. You can go down the final counter mine and then drop
down into the mine. The guide stuff says its the only surviving example
in Europe. Both were cut out of rock, so I don't quite understand how
the attackers intended to collapse it to bring down the wall. Unless
they simply intended to gain access to the inside of the castle.

What was the counter mine for? To get out?[/QUOTE]

No, so the defenders could attack the miners before the mine got under
the walls. Since they were cutting through rock the defenders eventually
found them by sound. The castle was eventually taken when some French
warships arrived off the coast and bombarded it. This was during the
religious strife during the reformation when Mary Queen of Scots was
very young and there was a series of regents.

Peter