Sunday, July 22, 2012

Drilling holes in granite... easy!

I needed a 2" hole in the back of our kitchen office area where the computer lives... Problem is, it's a jumble of wires, power cords,  USB cables, power-strips, LAN cables, DSL modem and Wi-fi router.  A real-eye sore.
So the wife wants me to fix it.  Solution?  Get the gear below the desk-top, and run the few cords through a 2" hole to below.  Second problem:  How to get the hole drilled.  Hire a Pro?  $100.  On second thought, maybe run through the wall?  The backsplash is slate tiles.  So back to drilling a hole.
I go to YouTube and lots of videos on how to do it.  Just buy the right diamond-encrusted hole saw and use lots of water while going REALLY slow.

I bought this 2" (50mm) hole saw off of Amazon (CLICK HERE) for just a few dollars, and it came in a week or so, wrapped in a nice re-usable ziploc sealed bag to protect the diamond dust cutting edge.

I read that one can make a small encircling rim to hold water around the targeted hole using plumber's putty... worked like a charm.

The trick is to mark the area with a grease pencil or small dab of white paint to show you where to start.  You begin by tipping the bit and starting just a small edge to get a bite, and as it starts to dig in, you slowly tip the hole drill to vertical to start the downward plunge.  The tip-start ensures the bit doesn't walk around, causing all kinds of mayhem and unwanted gouges and scratches.

It took about 20 minutes to slowly go through the 1" granite, with frequent stopping to cool my cordless drill.  The bit actually stayed cool to the touch with the little pond of water it was dipped in to drill.

Since the bit is only about an inch deep, it didn't make it through before bottoming out.  No worries, as I knew I was maybe 1 or 2mm from completely the hole.  I mopped up the residual water and just gave the center of the hole a moderate tap with a large hammer and just knocked the core out the bottom.  Cracked out pretty cleanly with maybe just a small lip...but that's on the bottom of the desk and won't be seen.

The finished product is fantastic, and after a quick clean up of the granite slurry and overspray, I was finished.

The shelf below the desk was made from 3/4" birch plywood, and stained, and installed using countersunk drywall screws (short).  The shelf is 10" deep and 24" wide, and dropped 8" from the bottom of the sliding desk drawer.

Super easy, after all, and not out of the realm of any DIY'er.  Good luck!

Matt