diamond coated drill bits

[steamshovel]

I am looking for a good place to buy American made diamond coated drill bits to drill a hole in hard material like granite and to be able to drill a hole 4"'s deep.


Preston

 

[ashaw]

Talk to your local granite counter top seller. They use diamond bits for drill holes in counter tops. They are your best source for information.

 

[plantman]

What size holes do you want to drill ?? Jim S

 

[JohnGreco]

Preston- I've been looking into this for some time now, and getting a diamond coated drill bit that is a jobber length (5-7") and not a hole saw bit is extremely difficult to find. I've actually considered going the way of the Egyptians and using the flat end of a metal punch/pen disassembly kit and put some sand where I want the hole, then keep throwing some sand in the hole as it goes. That should work, but I'm sure wouldn't give me the tolerances I'm looking for. Waiting for carbide tipped bits to arrive now, but I won't be trying them on granite.

 

[steamshovel]

I got a granite slab cheap and I am wanting to make a couple of mantel clocks made from the granite and will be putting columns into the base and top with 1/4" to 3/4" holes to be drilled. A bit extender won't work and no one seems to have anything. I could weld a shank extension on but my alignment better be dead on or I'll ruin the hole size.

 

[Ed McDonnell]

Here's a link I had archived in my "try it some day" folder on drilling granite with carbide bits. If you can get the piece under your drill press and can build the coolant dam, maybe it would word for you. I have not tried this, but it seems like a reasonable approach for a DIY project. As long as you have lots of time to kill, because I suspect it won't be a quick process.

How to Drill Through Granite, Stone, Cement, Glass...etc. » Curbly | DIY Design Community

Ed

 

[plantman]

I got a granite slab cheap and I am wanting to make a couple of mantel clocks made from the granite and will be putting columns into the base and top with 1/4" to 3/4" holes to be drilled. A bit extender won't work and no one seems to have anything. I could weld a shank extension on but my alignment better be dead on or I'll ruin the hole size.

Look on the internet for Star Drills. These are what the old miners used to make holes for there charges, and are still used today. Smallest one I have seen so far is 1/2 inch X 10"s. You hit them with a hammer and twist, hit and twist, hit and twist, etc. You can also buy a 10 piece set of diamond coated hole saw bits in metric sizes, from in China, on e-bay, but they won't drill 4 inches deep. Smallest American diamond coreing bits I saw were starting at 1 inch X 10, and going up by 1/8 inch for around $65.00. Jim S