Drilling through rocks

[MiamiCuse]

I have never drilled through rocks before and I am wondering how different it will be compared to drilling through solid concrete. I suspect it may be harder?

I have an exterior wall that is a 12" thick concrete block wall (8" block with a layer of 4" block), and on the outside of this is a layer of rock/stone face like this:

I want to add a hose bib on that wall. I have access from the inside and a copper pipe is near by that I can split off and run a 1/2" copper pipe there. I have a rotary hammer with concrete bits and I can chew through the

12" concrete block like butter, but I am not so sure about this rock...I don't want to end up pushing a piece of rock completely out, and if I can drill into it I don't know how clean the hole will be, will I end up cracking it into two?

I don't have a spare piece of rock or I would try to drill it just to see.

Thanks in advance,

MC

[Steve B]

I would be interested in this answer, also. I want to make a rock feature on a rebar skeleton, and I was wondering about drilling half way through the rocks to mount them on the skeleton's fingers. Wondering if the Makita roto-hammer I have would drill a hole or crack the rock. I have tons of rock I would like to get rid of if you would like some. They grow here. Every time you think you got them cleared, more pop out of the soil.

Steve

[gfretwell]

It really depends on what kind of rock you are talking about. In Miami it will be coral rock or limestone and a hammer drill will go right through it. They break up coral rock with a back hoe. I am not sure about what kind of rock Steve has in Utah. I collect rocks from our travels out west and I have picked up everything from soft sandstone you can drill with a pocket knife to some granite like material that would be tough to drill with a rotary hammer.

[MiamiCuse]

Not coral rock. It may be more like granite.

[Larry Fishel]

Knock out a small rock in a suitable place and drill throught the wall from the outside? Smash that rock. Mortar in a few of the pieces around the pipe. (Measure five times before you start drilling.)

[dadiOH]

When rock is quarried, they...

1. drill hole(s)

1. insert dynamite in hole(s)

Don't do #2.

[JIMMIE]

Be prepared for the rock coming off the wall. That's what happened the only time I have done this. My friend and I were drilling a hole through the wall into his basement with a hammer drill. It wasnt such a big deal, we epoxied it back in place.

Jimmie

[jamesgangnc]

Measure and figure out where to drill from the outside and then do it between the rocks.

[Jim Elbrecht]

I'm not a geologist but it looks like they might be shattered quartz- in which case you can only drill them with a diamond bit.

You might try a post to a geology group with a good color close-up of

3-4 rocks. They might be able to ID and tell you where they fall on Moh's scale. [or you can determine where it falls by scratching with some known substances- ]

Most rocks [in my part of the world] are drillable with a regular masonry bit- no hammering needed.

I'd try drilling first- if that doesn't work, go for the remove/shatter/re-install that someone mentioned.

-snip-

No problem- See above-

No problem- see above.

The 'spare piece' is sitting where the pipe comes out. Even if it ends up getting removed and a new mortar spot has to appear where it was.

Jim

[Pete C.]

Diamond core bit, with water, no hammer, drill from the outside in so you don't knock the rock loose.

[Steve B]

wrote

You name it, we got it. A lot of spongy lava rock here. Lots of sandstone type stuff. I just need to go out and drill some. Weather has just been dreary, and rain forecast for the next few days.

I need a bigger shop.

Steve

[JayTKR]

And, maybe try to find a place to start the drilling from the outside that is in the crevice/corner between 3 or so full rocks that are on the outside surface -- so that most of the rock drilling will be in the second layer below the surface rocks. This is just a guess on my part based on looking at the picture.

[Joe]

Totally agree. Milwaukee has diamond bits, hole saws, stuff like that. If you want to go easy on your budget, Harbor Freight has all manner of diamond products, blades, hole saws, drills. When you get through the veneer, then break out the brutal tools.

Joe