How to cut a slate slab (and how difficult is it)?

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Krome10

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Hi

An old slate slab has come up that I would like to use for a kitchen worktop. It's from an old snooker table and is 30mm thick.

I'll need to cut it roughly in the first instance so that I can move it and fit it into the car. I can then cut it more precisely once the unit is made and I have exact details.

I've never done it before... For a rough cut and at that thickness, what would be best to use? I have got:

- a large circular saw (are they all capable of cutting stone with the correct blade or are some machines for wood only)?
- a mini circular saw (Worx)
- an angle grinder (but with no discs so would need to buy whatever would be suitable).

Hoping to collect tomorrow, so any advice would be fantastic.

Many thanks
 

Jones

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Angle grinder with a diamond blade will do it quickly but can flake off bits of the edge on the top side as you cut. This doesn't always happen and may not be a problem particularly when roughing out. A jigsaw on very slow speed with a coarse tooth blade is surprisingly effective especially for corners. I've never tried a circular saw ,I expect the speed would be too high which will quickly heat and blunt the blade. Slate dust is a cause of silicosis so take precautions, cutting outdoors on a windy day is good.
 

Krome10

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Many thanks for the quick answers. I don't suppose I could trouble you for a link to the kind of blade I need? I'm just not too sure where to start. The angle grinder I have is an old 100mm Makita - model 9501B. Many thanks
 

Krome10

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That being said, I've just measured the blade and up to the point where the blade is held by the metal piece it is only 33mm. With the slate being 30mm, I'm guessing I'd need more clearance?
 

Fitzroy

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I cut up a 25mm thick slate with an angle grinder and one of these. Erbauer Masonry/Tile Diamond Cutting Blade 125 x 22.23mm

I was making a hearth and found I couldn’t get a straight enough line. Ended up getting a secondhand water tile saw off gumtree for £80. Made the final neat cuts and the sold it on for the same price 2 weeks later.

Edges required lots of sanding to get in good enough condition to leave inview
 

Ozi

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Might be worth getting a 9" angle grinder and diamond blade, I bought a cheep one from Argos when block paving my drive about 15 years ago very useful tool once you have it. You could possibly hire one if no further need afterwards.
 

niall Y

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That being said, I've just measured the blade and up to the point where the blade is held by the metal piece it is only 33mm. With the slate being 30mm, I'm guessing I'd need more clearance?
You could cut from both sides with the angle grinder. Its helpful to clamp a wooden batten to the slate with a couple of clamps. to guide the first few passes, which can be removed to finish the cut. That last 3mm could also be cut with a handsaw - in fact, the whole thing could be cut with a handsaw, which is what was used in the past. It's tedious but doable I adopter these methods when laying a slate floor, but when I fitted a slate window board , the guy who cut it for me, used a large overhead tile cutting saw. He had adapted somehow extending the table,and allowing for longer cuts.
You can also buy stone grinding cutters, to fit your angle grinder.And I'm sure you could improvise some way of using this to neatly dress the face of any uneven cuts
 

PDW125

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Cut 2:3rds through with a grinder and the Erbauer diamond disk from S’Fix and put a batten under and it will snap on the line - that will get you home.

Then keep an eye out for a Rubi wet bench on BookFace or Gumtree and buy that - loads of people buy the Rubi 200 to do one or two jobs and then trade them on. Will cut 30mm slate all day long.
 

Fergie 307

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Go to your local hire shop and get a proper diamond blade disc cutter. You really want a big petrol one with water cooling. The big blade makes it much easier to keep to a line, and you can connect up a hose to dribble water into the cut as you go. The suggestion of using a wood batten as a guide is good. This is how I have always done it, whether cutting slate, paving slabs or whatever. The water also stops dust, and gives a much better finish.
 

GweithdyDU

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I used an irregular piece of Welsh slate with one straight edge into a hearth and needed to cut out a section where the grate stuck out. over 3" thick and I managed with a mechanical hacksaw blade. You can even use a cheap cross-cut wood saw. I live in North Wales's former slate quarrying area and around here you often see it cut into all shape and used almost like plywood. From cold cupboards for milk, to speaker cabinets and name-plaques; it is a relatively easy material to work with. Yes with the water, definitely. I've not tried it, but I reckon a skill saw with an RCT blade pushed very gently and with lots of water would have it. Be aware of power tools and all that water though and use a 110v if you can. I've been surprised over the years over how easy slate is to work with although I only have experience of Welsh slate. Other slate, like Spanish for instance, behaves quite differently (more crumbly).

Good Luck.

PS it will stuff-up your blades
 

Craig22

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I guess I'm lucky that I live close to Home - Abingdon Stone & Marble . They have done slate work for me (a record deck plinth believe it or not).

So it might be worth searching locally for something similar. Perhaps search for "monumental masons" who make gravestones etc.

Craig
 

Jonm

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For the final cuts it would be a good idea to make templates from corex (or similar) to make sure the angles/widths are all correct, as the professionals do. As for cutting them you could try a local stone worktop supplier to see if they will cut them for you.
 

Adam W.

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Hi

An old slate slab has come up that I would like to use for a kitchen worktop. It's from an old snooker table and is 30mm thick.

I'll need to cut it roughly in the first instance so that I can move it and fit it into the car. I can then cut it more precisely once the unit is made and I have exact details.

I've never done it before... For a rough cut and at that thickness, what would be best to use? I have got:

- a large circular saw (are they all capable of cutting stone with the correct blade or are some machines for wood only)?
- a mini circular saw (Worx)
- an angle grinder (but with no discs so would need to buy whatever would be suitable).

Hoping to collect tomorrow, so any advice would be fantastic.

Many thanks
Hire a petrol disc cutter with a diamond blade and plug it into the hosepipe, the dust will be a horror show otherwise.
 

quintain

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Might be worth getting a 9" angle grinder and diamond blade, I bought a cheep one from Argos when block paving my drive about 15 years ago very useful tool once you have it. You could possibly hire one if no further need afterwards.
I am not a lover of 9" angle grinder due to frequent viciuos kickbacks. I realise I will be told the tool has to be used correctly but my (then early 2000s) 2 x very competant farm labourers suffered severe, possible serious injury, kickbacks with the tool. Sufficient for me to realise I had to prohibit its use. I have now set it up as a bench mounted (v infrequently used) chop saw....I replaced the 9" angle grinder with a petrol disc cutter with a diamond blade (edited after reading Adam W input)
 

Tony51

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Do not cut half way and try to snap the rest slate is laid down in layers when first formed it will take the path of least resistance and you can end up with a large lump cleaved off. Cut all the way through with a disc cutter support both sides securely .that way you should get a clean cut.
 

Cordy

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Not relevant, but I needed to cut some roofing slate; did it easily with a hack-saw
 

dickm

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The deWalt diamond blade disc in an old 4" Bosch angle grinder made short work of slate that thick for various name plates etc. At worst, wear an N95 mask, preferably a powered respirator and do it outside.
 

Ozi

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I am not a lover of 9" angle grinder due to frequent viciuos kickbacks. I realise I will be told the tool has to be used correctly but my (then early 2000s) 2 x very competant farm labourers suffered severe, possible serious injury, kickbacks with the tool. Sufficient for me to realise I had to prohibit its use. I have now set it up as a bench mounted (v infrequently used) chop saw....I replaced the 9" angle grinder with a petrol disc cutter with a diamond blade (edited after reading Adam W input)
You're absolutely correct they do have the potential to be very dangerous, one of the things I was taught and stick to religiously was to expect it to kick so your ready for it and always work with space around you to allow for it. Plus keeping the area tidy and positioning the guard and handles to best advantage for every cut. Still the second scariest tool I use after a grinding wheel.
 
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