Hole saw in granite

[Keexet]

After the latest stroke of genius on a fun idea, the question popped up in my head, how the heck do you get a hole in a granite slab?

It's about a 2cm thick polished granite slab I would like to have a hole about 60 mm in size. I have a drill kit for tiles/concrete, but is it good enough? How do you go about it practically? Water cooling? Is it even possible with handheld equipment, or do you need a pillar drill?

It's a fairly unambitious project, so if the planning gets too complicated, I'll probably shelve it. I can "sacrifice" one of my hole saws for this if there's a risk it'll become unusable afterwards.

 

[Daniel_82]

I don't know if it's any help, but a couple of years ago I laid stone flooring, black granite, in the hallway of my old apartment. I had trouble cutting it to fit the edges. Solved it by using an angle grinder with a diamond blade. It was quite thick flooring, I think it was 1-1.5 cm.

My amateur guess is that it should be possible, the question is more about how to do it neatly. If you have a machine with a guide or whatever it's called so it cuts straight with a good blade, I guess it could work. The question is if there's one to rent.

But as I said, this is just my guess, and the floor I have experience with is not a stone countertop. However, if you haven't already thought about it, the piece you cut out might weigh quite a bit, so it's probably good to consider how to manage that piece so it doesn't break or hurt someone.

Maybe it’s also worth testing on a small piece so you don't ruin what I guess is a fairly expensive countertop.

I forgot to mention that some of the stone tiles cracked, even if you weren't super careful since there were quite a few extra tiles available. Hopefully, someone else can give some good tips and help.

 

[hempularen]

I can't say that I know. But I guess you need a hole saw with a diamond blade. The one you have for tiles probably cuts with carbide, and I don't think that works on pure stone, at least not within a reasonable time frame.

Ex. Jula sells such for a reasonably affordable price.

 

[MathiasS]

That's much easier than you think. I made a 100mm hole in paving stone made of granite. Used Jula's blue hole saws with diamond cutting edges. I remember we used the drill press for this, but it would probably work fine freehand.

If you want a perfect edge that is visible, you may need to reconsider, but a hole was made without any major chips.

 

[zeveta]

If you have the patience to wait, there are very cheap diamond hole saws on Ebay from China. I have ordered and tried them with good results. I used a regular battery-powered drill and had a piece of wood with a hole cut out placed as a template on top of the stone. Water cooling is necessary, but it's enough that the cutting edge goes into a water bath. I used a regular plant sprayer and a towel as a barrier around it.

 

[nino]

A hole saw for the angle grinder should work fine, you usually manage the edges but you have to be careful to keep the saw straight as it tends to pinch when it becomes that thick.

Predator is what they're called on kgcverktyg.se

 

[MathiasS]

In the drill press, we ran at low speed to avoid splashing with water, worked fine.

 

[Erik Salhammar]

After the latest stroke of genius on a fun idea, the question popped into my head, how on earth do you get a hole in a granite slab?

It's an approximately 2cm thick polished granite slab that I would like to have a hole about 60 mm in size. I have a hole saw set for tiles/concrete, but is it good enough? How do you proceed practically? Water cooling? Is it even possible with handheld equipment, or do you need a drill press?

It's a fairly unambitious project, so if the project planning gets complicated, I might shelve it. I can "sacrifice" one of my hole saws for this if there's a risk it becomes unusable afterward.

I drilled a 60mm hole in a 7cm thick slab of gneiss. Used some cheap thing from Jula and it worked fine, just make sure to pour on water to cool the steel a little.