# Drill bit that works with slate?



## AquaNeko (Jul 26, 2009)

I'd like to know two scenarios 1. the appropriate drill bit type to use on slate and 2. the next best option if you're in a pinch drill bit to work with slate.

I recieved a slate item from a member which I'm thinking of doing a little modding with a drill (likely a dremel if not then the corded drill I've got). Thanks in advance.


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## InSpirit (Mar 14, 2009)

You can use a simple masonary drill bit. Be even better to use a masonary drill bit chucked in a hammer drill. In something harder like granite I'd use a "Groo-V Granite and Marble Drill Bit." You can get this at CRL.


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## Mr Fishies (Sep 21, 2007)

Not sure sure I'd use a masonry bit and hammer drill on slate - pretty good chance you'll shatter it, some slate, especially when thin, is pretty "delicate" (for stone). Maybe with the hammer turned off and plenty of water but that would be my #2 solution.

#1 solution would be a glass/ceramic bit with a regular (non-hammer) drill. They look like the attached image - a standard CT, Rona type item. As previous, use water to keep it cool, don't lean into it too hard and the bit will last a lot longer. If you lay the slate flat on a bench/floor wherever, build a little round plasticine (for example) walls to keep a shallow pool of water where you want to drill and it will go easier and faster.


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## InSpirit (Mar 14, 2009)

You're right. Especially the thick stuff being sold by Home Depot and Lowes. The stuff just shatters along the layers when you cut it down with diamond tile saw. I just gave away a bunch of caves built with a box of this slate. But if it's of better quality, it will work. I use to drill slate bottoms for driftwood brought into a wholesaler. A slate company use to give us the off cuts for free. Thanks for the correction.


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## InSpirit (Mar 14, 2009)

AquaNeko what you need these holes for? Application wise. I have these spear point drills. If you don't want to say here. You can pm me if you want.


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## 50seven (Feb 14, 2010)

Mr Fishies said:


> Not sure sure I'd use a masonry bit and hammer drill on slate - pretty good chance you'll shatter it, some slate, especially when thin, is pretty "delicate" (for stone). Maybe with the hammer turned off and plenty of water but that would be my #2 solution.
> 
> #1 solution would be a glass/ceramic bit with a regular (non-hammer) drill. They look like the attached image - a standard CT, Rona type item. As previous, use water to keep it cool, don't lean into it too hard and the bit will last a lot longer. If you lay the slate flat on a bench/floor wherever, build a little round plasticine (for example) walls to keep a shallow pool of water where you want to drill and it will go easier and faster.


+1

Slate is too brittle and soft; a masonry bit will not work, and could shatter or flake the slate. Use the glass bit, or if you are desperate, you can use a regular HSS drill bit, but you'll make it dull pretty quickly.

PM me if you're stuck


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## InSpirit (Mar 14, 2009)

*masonary drill bit on slate*

Neko... I drilled out a cheap piece of slate using a 1/4" masonary drill bit without precussion of my hammer drill. I had the speed dialed up and I noticed it cut like butter through the slate piece. The holes were drilled close to each other to see if the piece would shatter. Nothing. Don't be afraid to try it.


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## AquaNeko (Jul 26, 2009)

Thanks for the help. I was thinking of drilling some viewing holes on the sides of the slate I have so I can see inside when I shine a light to see if any jiggy jiggy action is going on inside the little hide cave.  

It's on my to-do list but right now I gotta ramp my garden plans up first before I get all David Cronenberg on the slate with my dremel.


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## BillD (Jun 5, 2006)

A masonry bit goes through slate like a hot knife through butter.


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## KhuliLoachFan (Mar 8, 2008)

+1 to everybody who said masonry bits bore slate easily. Better to keep it wet though. I have even drilled it while running a drip of water from an airline tube.

W


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## wildexpressions (May 3, 2010)

my wife uses a masonary bit and a small hammer drill to drill slate all ofthe time. Sometimes it goes fast, sometimes slow. Not all slate is the same by any stretch.

She drills 3/4 inch hole in pieces up to 2 inches thick so that she can run a 6" long lag bolt though to attach them to wood to reinforce them while the glue dries.

I don't think she has ever broke one.


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