Rock Saws

As BurntBear says a diamond blade is needed. Depending on the size of the material and how much your willing to loose on the cut a tile cutter will work fine. A lapidary saw will work better for smaller stuff and leaves a better finish on the ruff cut as well as reducing the amount of material you'll loose in the cut.

Using a tile cutter you'll have to modify it somewhat. First is to rig a vice to it for the rocks. Second is a weight to counter the retraction spring with enough weight to provide steady but not to hard down force during the cut. And last a way to lock the power switch on so you don't have to hold it the whole time.
For large work you'll need an extra basin under the saw and pump to keep water going back into the primary basin of the tile cutter and maybe rig some additional splash gaurds.
 

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Yup, tile saws work. Not fantastic, but it's a cheap way to cut. This was my first cut with a tile saw; a piece of petrified wood.

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Thanks y'all. Looks like a tile saw initially. Then graduate LOL. If you're dealing with large rocks, you might better have both anyway.
 

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I haven't been cutting rocks all that long but I've had luck with my tile saw. I use a professional 10" with a horizontal table so it's a push saw. So as not to waste good rock I bought a thin lap blade and devised a feed system using pulleys and weights.
Because my saw has no cover like a real slab saw there is some misting requiring a face mask.
Many rock saws use mineral oil for a lubricant. I use an emulsion, oil and water mix I buy at NAPA. It's what machine shops use in their machines. It's cheaper than mineral oil and easier to pump. It does mist a bit though. It's probably safe as it's been in machines forever but I'd rather not breath it.
I built several rock vices based on designs others have bought or made.
If I need to cut something really large I will probably take it to Mama's Minerals here have them do it rather than bust it up and loose valuable rock.
 

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Good advice so far!

You can also just use your hands to feed the rock into the saw. I've done it that way the last 5 years.
Building a "splash guard" may be a good idea, though!
 

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Good advice so far!

You can also just use your hands to feed the rock into the saw. I've done it that way the last 5 years.
Building a "splash guard" may be a good idea, though!

I've also used my hands for smaller stuff. There is a Vice Grip pliers made for work on a drill press. It has a threaded stud that is placed in one of the holes on the press and secured with a nut. When clamped down it hold really well. I drilled various holes on my rock saw's feed table so I could find the best position for the tool and rock.
 

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Another thing: use water as a coolant. Plenty of water.
Oils can seep into materials, making a mess. And also making your material "treated", which you need to disclose should you ever sell.

Perhaps not a thing to worry about as a hobbyist, but should you ever sell its good to know. :)
 

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Another thing: use water as a coolant. Plenty of water.
Oils can seep into materials, making a mess. And also making your material "treated", which you need to disclose should you ever sell.

Perhaps not a thing to worry about as a hobbyist, but should you ever sell its good to know. :)


Good point about oil. I have a piece of turquoise someone had cut slabs from and I bought the remaining rough. Because of the oil used I couldn't tell what the stone was and the seller didn't know either. They were in a house she bought. The stone just appeared like a dull greenish not too impressive.
I cut a slab from the stone and a beautiful deep blue and obviously turquoise appeared. One of those wow moments.
I find the emulsion I mix doesn't appear to soak into even soft stones. I dilute one pint of the oil to about 4 gal water. But like you said plain water works fine too. I was hoping to add some life to the blade and cut down on rust.
 

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The best lifesaver for blades are not using to much pressure, because it "forces/pushes" the metal over the diamonds, making it slow darn quick.
I know a guy which used his (quality) blade for more then 5 years just by this tip!
And that is the main reason I cut by holding the stone in my hands, I can "feel" better how much pressure is applied to the blade.

an occasional sharpening with a metal file can also help, should it start to cut slow.
 

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The best lifesaver for blades are not using to much pressure, because it "forces/pushes" the metal over the diamonds, making it slow darn quick.
I know a guy which used his (quality) blade for more then 5 years just by this tip!
And that is the main reason I cut by holding the stone in my hands, I can "feel" better how much pressure is applied to the blade.

an occasional sharpening with a metal file can also help, should it start to cut slow.


I've heard that some when a blade in under performing will reverse the blade. Put it on opposite the direction arrow. Others will cit into a common brick saying it will renew the diamonds. Not sure about renewing them, more likely like you said about the metal being forced over the diamonds. But like said forcing any cutting tool will generate much more heat and shorten it's life.
In machine work every material has a correct cutting speed, lube. and pressure. Probably rocks are the same. At least with speed and pressure.
When industrial diamonds were more pricy my company would send core bits to a place that would turn the diamonds over and reset them. Not sure if that's exactly what they did o the bits but that's what I remember anyway. A six or eight inch core bit is still pricy.
I just remembered something that struck me strange. In older days the preferred lube for machining cast iron was lard.
 

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I know some that use the brick method to. But I prefer a metal file. The idea is just to remove the metal which now probably sits over the diamonds.
 

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An easy way to think of diamond blades to just think of them as big files. Ordinary hand files have a cleaning tool called a file card~ its essentially a wire brush used to clean out the channels of a file that have filled with shaving material and compacted between the cutting edges. Diamond blades are essentially the same thing~ as they cut material builds up between the cutting edges and fills them in. Using a brick or other material can clean out the gaps renewing the abrasive surface somewhat and extending the life of the blade.
As EU pointed out controlling the pressure on a cutting blade extends the life as well. This is because the heat of the friction can fuse the cut materials in the gaps between the diamond surfaces. Same goes with files ;)
Reversing a blade can also knock out debris from between the surfaces as well but also exposes the sharper edges on the back side of the diamonds that have not been dulled *and are probably even sharpened* by the cutting direction of the disc. Diamond disks that have a direction of rotation noted are set up that way because the manufacture orients the abrasives from maximum cut in that direction.
Sharpening the edge of a cutting disk does not really make it sharper~ what it does is remove the metal that has deformed and mushroomed over the diamonds at the edge of the disk. Removing this material exposes the diamonds and does effectively bring life back to the cutting operations.

For core bits that are sent back for refurbishment often the manufacture will debond the diamond cutting bits, flip them and maybe sharpen them, then rebond them to the bit.
 

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