How to drill in marble?

[AlexThePalex]

I have a question, how exactly do you drill in marble, as I have never done it before.

I need to attach a new glass shelf over a sink to a marble slab that's about 1 inch/2,5 cm thick.

Can you simply use a masonry drill bit or do you need something special? I thought I'd ask before trying anything, because I don't want to ruin the marble.

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[Alan m]

get a diamond  tipped core bit.  or use an sds bit with the hammer off
use a steel nail to create a centre hole

 

[Wuffles]

Marble's pretty soft (from experience) and I wouldn't use a hammer drill on it as it can also be fragile along the veins.

If you're in a desperate rush to get into it, take my advice and kick things off with a tile bit (for the pointy start) or a diamond bit then switch out to a decent masonry bit. That's what I have used before and had no problem.

Someone will be along with better advice shortly.

 

[tjbnwi]

Diamond hole saw.

Tom

 

[AlexThePalex]

Thanks for the advice so far. I just need to make 4 small holes of 6 mm (1/4th) diameter, nothing more. Is a masonry bit really out of the question?

 

[tjbnwi]

Thanks for the advice so far. I just need to make 4 small holes of 6 mm (1/4th) diameter, nothing more. Is a masonry bit really out of the question?

As long as your not real close to a vein the masonry bit should be okay. Medium pressure, low speed, as mentioned above a nail will give you a starting point or make a template.

I have the full line of Bosch diamond hole saws. I can buy cheep ones at the big box stores here for less than $10.00. Here is the one I do have;

http://www.amazon.com/dp/B003TO5F54?tag=price1264-20&m=ATVPDKIKX0DER

Tom

 

[Stephen B]

Diamond hole saw.

Tom

Alex, these diamond hole saws are pretty common down here; available from most hardware and tile supplies and are 'relatively' inexpensive. They are available in small diameter sizes within your requirements.

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The trick to using them is to dip the lip in some water, then apply the lip edge at an angle to the marble and at low speed, then as it starts to cut straighten out and drill your hole through. You should re dip in water as the drilling proceeds.

If you apply the saw straight on to the marble there is a great danger it will move across the marble surface.  [eek]

You may know all this but some others may not.  [smile]

[member=5277]Alex[/member]

 

[tjbnwi]

To keep the bit cool, drill through an ice cube, this packs the hollow of the bit, friction melts the ice, water carries heat away. You can also drill threw a wet sponge, squeeze to release water as needed.

I make a plywood drilling guide, drill the 1/4" hole hold the guide in place it keeps the bit from wondering.

Tom

 

[CrazyLarry]

For marble a diamond bit is IMO overkill more appropriate for porcelain.

You really want an arrowhead TC bit, trend or armeg are both good makes.

You can drill it in one go with a 6mm so long as you either spray with water to keep it cool or gently squeeze a sponge resting above the bit.

If accuracy is critical though I'd start with a 3mm to a 2mm depth then switch to the 6mm

In any case rotary only and keep the speed down.

A masonary bit might be ok, but they come in a range of tip shapes many of which will skate, an arrowhead will be reasonably cheap less than a diamond bit for example and get you 4 holes in the right place quickly

 

[neeleman]

I therefore use the Pro-Fit Diamond Dry drills.
Sold separately from Ø5 to Ø120 mm or in sets.
And can be used in a normal bit adapter or Jacobs chuck.
Sold at: Borentappenschuren NL

 

[AlexThePalex]

Thank you all for your advice.

I think I have such an arrow bit tucked away somewhere deep in a drawer, I'll try to dig it out. I had the idea to use a piece of wood with a hole in it to keep the bit in place, glad Tom confirmed that can work.

At least the owner still has the pieces off the old shelf which was broken, so I can make some test holes first.

I'll talk to her about getting a diamond bit, she'll have to foot the bill.

Thanks again.

 

[Wuffles]

Thank you all for your advice.

I think I have such an arrow bit tucked away somewhere deep in a drawer, I'll try to dig it out. I had the idea to use a piece of wood with a hole in it to keep the bit in place, glad Tom confirmed that can work.

At least the owner still has the pieces off the old shelf which was broken, so I can make some test holes first.

I'll talk to her about getting a diamond bit, she'll have to foot the bill.

Thanks again.

You probably won't need it, just kick it off with the tile bit and see how you get on.

They are a couple of euros for a 6mm one on eBay.

 

[CrazyLarry]

The plywood trick works but is better for use with diamond bits such as the pro-fit ones below. Although if you are drilling enough to need those I'd also use a guide with a suction foot that takes a water supply from a pressurised sprayer. You can get small ones with dedicated holes for 5 6 8 10 mm.

For an arrowhead bit into soft material like marble just put a piece of insulation tape over the drilling spot, drill an indent (no more) then peel off the tape and start drilling wet. Much quicker and no need for 3 hands

 

[AlexThePalex]

Thought I'd follow up on this hread with the result. Took some time because the homeowner backed out originally, but I got a call this week she wanted it to be done now.

I got a drill bit for glass, a simple bit with an arrow shaped point, and it was a piece of cake to drill through the marble. Marble feels realy hard to the touch, but for drilling it turned out to be pretty soft. The bit went through very easily, without any wander, and the dust felt really soft like chalk dust, or baby powder if you will. I wouldn't have thought that.

Thanks again for all the advice I got. The lady is very happy with the result.

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