Cutting Indian sandstone

[Tricky Dicky]

Just been laying a sandstone patio, having finished laying the full flags I am now starting on all the cuts. I tried one today thinking the angle grinder would chew through it in no time. To my surprise the grinder with a stone cutting disk was struggling, in the end I used it to score the cut line and ended up splitting it with a chisel which was OK for the one done but some of the other cuts need to be neater. The hardness of the stone has surprised me some of the shards chiseled off are so sharp you could perform surgery with them. Would investing in a diamond saw prove any better? I see Aldi has one on offer this week.

Richard

[John Rumm]

AG with a diamond disc should do fine. The SF own brand diamond disks do
surprisingly well on hard materials.


--
Cheers,

John.

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[JimK]

The reason they are so hard is why they are so thin...

Jim K

[harry]

On Thursday, 20 August 2015 23:34:47 UTC+1, Tricky Dicky wrote:
> Just been laying a sandstone patio, having finished laying the full flags I am now starting on all the cuts. I tried one today thinking the angle grinder would chew through it in no time. To my surprise the grinder with a stone cutting disk was struggling, in the end I used it to score the cut line and ended up splitting it with a chisel which was OK for the one done but some of the other cuts need to be neater. The hardness of the stone has surprised me some of the shards chiseled off are so sharp you could perform surgery with them. Would investing in a diamond saw prove any better? I see Aldi has one on offer this week.
>
> Richard

I only buy diamond disks anyway for the angle grinder.
But there are disks and disks.
The cheapies are not as good.
Down to the amount of diamonds in the mix I think.
But IME the cheapies are good enough for the Indian sandstone.
Won't look at granite
I laid quite a bit myself three years ago.

[Tricky Dicky]

Hi John, looked at the SF site could not find any SF own make, are we talking about the Erbauer ones, one has a lot of good reviews from both trade and DIYers for about £15?

Richard

[The Natural Philosopher]

On 20/08/15 23:34, Tricky Dicky wrote:
> Just been laying a sandstone patio, having finished laying the full flags I am now starting on all the cuts. I tried one today thinking the angle grinder would chew through it in no time. To my surprise the grinder with a stone cutting disk was struggling, in the end I used it to score the cut line and ended up splitting it with a chisel which was OK for the one done but some of the other cuts need to be neater. The hardness of the stone has surprised me some of the shards chiseled off are so sharp you could perform surgery with them. Would investing in a diamond saw prove any better? I see Aldi has one on offer this week.
>
> Richard
>

angle grinder of serious power with a diamond disk will piss on it.



--
New Socialism consists essentially in being seen to have your heart in
the right place whilst your head is in the clouds and your hand is in
someone else's pocket.

[Dave Liquorice]

On Thu, 20 Aug 2015 15:34:42 -0700 (PDT), Tricky Dicky wrote:

> I tried one today thinking the angle grinder would chew through it in no
> time. To my surprise the grinder with a stone cutting disk was
> struggling,

"Stone cutting discs" fails the "fit for purpose" test of the SoGA
IMHO.

A Diamond blade ought to cut better and last longer.

> ... in the end I used it to score the cut line and ended up splitting it > with a chisel which was OK for the one done but some of the other cuts
> need to be neater.

Neater? This is natural stone you don't see natural stone in the wild
with polished faces and razor sharp corners.

I've found that one can "cut" the rather large through stones for
drystone walling by treating it like glass or tiles: "score and
snap". Scratch along the line where you want the cut, I use the
corner of a 1" chisel in an SDS drill. Just run the chisel along at
45 degrees or so a few times so there is a definate cut maybe 1/8"
deep and V shaped to the chisel. Turn stone over and support on 1"
battens that run parallel to, equal distance and as far from the
score as possible. Then give the stone a well spread reasonable thump
above the score. I just drop the end of 5' length of 8x3 from about a
foot, the 8" dimension aligned with the score. Stone just drops in
half along the score.

These stones are local sandstone (which is quite a hard dense
sandstone) about 2 to 4" thick and up to 3 x 2 feet so the battens
can be a foot or more from the score. It might not be so
easy/succesful if the battens have to be much closer to the score.

With say less than a foot from score to batted I'd try with the score
upper most and a single batten underneath with the edge aligned to
the score with the smaller bit of stone left completely unsupported,
stand on the supported bit and drop the 8x3 onto the unsupported bit
as far from the score as possible again with the 8" dimension aligned
with the score.

What is happening is that the bottom of the starts a crack (or lots
of micro cracks) in the stone which you make propergate through the
stone by suddenly flexing it open. Given this making the score with a
chisel may work better than the clean, ground, cut of an angle
grinder, the whacks from the chisel will create micro cracks.

--
Cheers
Dave.

[Fredxxx]

Are you sure this wasn't a "steel" cutting disk?

Would certainly recommend a diamond disk, they last ages.

[Dave Liquorice]

On Fri, 21 Aug 2015 09:04:13 +0100, The Natural Philosopher wrote:

> angle grinder of serious power with a diamond disk will piss on it.

Just as well there is some piss about, you can use it to control the
dust.

Score 'n snap, only generates a bit of grit and a few flakes. B-)

--
Cheers
Dave.

[The Natural Philosopher]

I've cut a lot of sandstone. Score and snap doesn't work on 1-2" thick slabs

[Capitol]

Tricky Dicky wrote:
> Just been laying a sandstone patio, having finished laying the full flags I am now starting on all the cuts. I tried one today thinking the angle grinder would chew through it in no time. To my surprise the grinder with a stone cutting disk was struggling, in the end I used it to score the cut line and ended up splitting it with a chisel which was OK for the one done but some of the other cuts need to be neater. The hardness of the stone has surprised me some of the shards chiseled off are so sharp you could perform surgery with them. Would investing in a diamond saw prove any better? I see Aldi has one on offer this week.
>
> Richard

I find any diamond disc works well, but always try to use lots of water
when cutting which seems to extend the blade life. Most tile saws IME
don't have enough power for this application.

[Fredxxx]

I have a tile saw table which as you say runs the blade in water.

However I also use a 9" blade on blocks and stone dry without ill
effect. The blade still lasts ages.

I've also used a 4.5" diamond blade on ceramic tiles without any
breakages or issues.

Why this need for water?

[Tim+]

Dust control. Rock dust ain't good for your lungs.

Tim

[GMM]

On 20/08/2015 23:34, Tricky Dicky wrote:

> Just been laying a sandstone patio, having finished laying the full flags I am now starting on all the cuts. I tried one today thinking the angle grinder would chew through it in no time. To my surprise the grinder with a stone cutting disk was struggling, in the end I used it to score the cut line and ended up splitting it with a chisel which was OK for the one done but some of the other cuts need to be neater. The hardness of the stone has surprised me some of the shards chiseled off are so sharp you could perform surgery with them. Would investing in a diamond saw prove any better? I see Aldi has one on offer this week.
>
> Richard
>

I've been using Aldilidl discs: Bought two packs a while ago, thinking
I'd run out quickly and I'm still on the same disc after a couple of
years of occasional cuts on stone (limestone, granite) and concrete.

If you want to keep the dust and noise down, use the disc to make a
shallow score, then snap. I tend to just give a few passes to go all
the way through. It's worth doing it somewhere where the fall-out won't
be a problem, like the end of the garden.

[dennis@home]

On 21/08/2015 10:44, The Natural Philosopher wrote:
> On 21/08/15 09:24, Dave Liquorice wrote:
>> On Fri, 21 Aug 2015 09:04:13 +0100, The Natural Philosopher wrote:
>>
>>> angle grinder of serious power with a diamond disk will piss on it.
>>
>> Just as well there is some piss about, you can use it to control the
>> dust.
>>
>> Score 'n snap, only generates a bit of grit and a few flakes. B-)
>>
> I've cut a lot of sandstone. Score and snap doesn't work on 1-2" thick
> slabs
>
>

Just do a score of 95% depth and it will.

[The Natural Philosopher]

By definition, that isnt a score...

[Phil L]

"Dave Liquorice" <allsortsn...@howhill.com> wrote in message
news:nyyfbegfubjuvyypb...@srv1.howhill.co.uk...

It doesn't work with indian stone I'm afraid, I've recently laid 200m2 of
this stuff and apart from the fact that diamond blades wear down very
quickly, scoring halfway through often has no effect on which way it will
snap, about 50% of the time it snaps nowhere near the score and makes two
useless pieces, and this is about £17 per m2

[Fredxxx]

Would that be a score of 5% leaving 95% of the material?

Or are we discussing a deep cut? There is a difference!

[Phil L]

"Tricky Dicky" <tricky...@sky.com> wrote in message
news:83485b96-f82d-42f5...@googlegroups.com...

Diamond blade, B&Q trade have them for a tenner (200mm)
Indian stone wears them down quite quickly, like ten times quicker than
concrete, but you should get 50 or 60 cuts out of one disk.
Don't try scoring and snapping because Indian stone snaps with the grain

[Dave Liquorice]

On Fri, 21 Aug 2015 10:44:40 +0100, The Natural Philosopher wrote:

> I've cut a lot of sandstone. Score and snap doesn't work on 1-2" thick
> slabs

Works on the lumps I have but then most are about > 2" thick.

Whats the problem on thiner stuff? No following the score line? A
solution might is proabbly a better (deeper sharper) score and use
the score up method. Waste end totally unsupported, the "good" end
fully suported and stood on. The the 8x3 dropped onto the waste say
4" from the score.

You also need to apply the force over a long section of the score at
the same time, hence the 5' length 8x3 which also has a fair bit of
gentle umph when dropped a foot. A lump hammer is too concentrated.

--
Cheers
Dave.

[John Rumm]

Yup that's the one...

[Tricky Dicky]

Thanks all, I have bought a diamond saw and weather permitting will have a go at it today.

Richard

[The Natural Philosopher]

On 22/08/15 08:35, Tricky Dicky wrote:
> Thanks all, I have bought a diamond saw and weather permitting will have a go at it today.
>
> Richard
>

I pissed through my last awkward shaped bits of sandstone with a hired
big grinder and diamond blade. In about 10 minutes. The hire guy said
'didn't it work' I said' It worked so well I am finished'

I DOD manage some with a tile saw but it took forever.

[Tricky Dicky]

Well the term "like a hot knife through butter" certainly applies to the diamond saw. I have got all the cuts I need for now just need to lay them probably Monday, weather and F1 on Sunday not permitting. Then it's a couple of steps and 3mts. of single flag footpath past the conservatory up to the hard standing. That will leave probably a couple of days pointing up all the joins.

Thanks John and all who responded.

Richard