DIY How to cut a sink hole in Granite, Quartz or Marble.
Cutting a hole is a stone counter top sounds like an impossible task for a DIY'er. Professional stone workers will use grinders and bits that cost several hundred dollars. But I was able to do it with tools that cost $41.00.
If you'd rather get straight to the video, here it is:
I used:
1. 4.5 inch turbo rim diamond blade. $10.15 with free shipping on Amazon (affiliate). http://amzn.to/2wRizuD Home depot carries it for $10.97
2. 4.5 inch angle grinder for $30. I used a Ryobi, but any brand will work.
3. Something to place your slab on. Most people use two horses. I placed two left over 5" vinyl Fence posts on the ground. Equally sized lumber should work just as well.
4. 1 inch wide masking or painters tape to place on your cutlines to prevent chipping.
Setup:
I placed the slab on my vinyl fence posts, in an area that I didn't mind getting dusty. You'll want to use a dust mask, and safety glasses. If you're cutting with water, you'll need a hose pipe with a trickle of water running on to your slab. Cutting stone is a very messy project. You can cut dry , but you'll produce a horrendous amount of dust which goes everywhere, probably including your neighbor's house.
You can cut with water, which reduces the amount of dust and keeps the cutting blade cool, extending its useful life, but the tools that I used were not meant to be used with water. I took safety precautions, such as using a GFCI outlet and using basic electrical safety. I've never been shocked, but it's always a risk.
Use the paper template that comes with your sink as a guide to lay out your tape.
Use the paper template to trace your cut lines on the tape. Pro's use a wax pencil, but I like using a permanent marker which was easier to see when the dust starts to cover the slab.
Technique
I Started by making a plunge cut and ensured my cuts were approximately 1 to 2 mm inside of the lines to give myself a buffer.
My sink was rectangular and had relatively sharp corners. I was unable to cut completely through the slab at the corners due to the geometry of the blade being round. I made a second smaller rectangular hole about an inch smaller then my final hole. I then cut away the material from the middle of the hole, outwards.
If you have a oval or round sink, you use a different technique. Instead of making a plunge cut, you'll make a shallow 1 to 2 mm cut and go all the way around your cut lines until you make a complete circuit. You'll then go a little deeper with the next circuit and keep going around until you completely cut through. There are several videos on YouTube that shows this technique.
Your next step is to drag the tip of the angle grinder blade along the edges of the sinkhole to remove any deep scratches and unevenness. You never want to push the tip of the angle grinder blade as it will result in gouges.
Please watch the YouTube video at the top of the page that I created to get a more detailed idea of how I did it.