Cutting through quartz requires some serious drilling |
More Lifestyles

Cutting through quartz requires some serious drilling

The Washington Post
Hammer drills and rotary hammers (also known as rotary hammer drills) can also drill through some types of rock, and they’re great for making holes in concrete.

Question: I want to thread a 12-foot pipe through a hole in a large rock and into the ground to support a birdhouse. The rock would remain on top of the ground, but it would anchor the pipe better and more attractively than my current arrangement. I can take the rock to a shop, but where can I go to get someone to drill a hole about three-quarters of an inch wide through a quartz rock about eight inches high?

Answer: To drill a hole that wide and deep through stone — especially a particularly hard type such as quartz — is a job for a core-drilling bit impregnated with diamond abrasive and a drill that feeds water down through the bit to keep the tip cool and rinse away debris. You might be able to find a countertop manufacturer who will cut the hole for you, because these fabricators use diamond core bits to cut holes for pipes to faucets. However, the bits they typically use are just a few inches long, enough to go through countertops.

Companies that specialize in concrete drilling and sawing are a better fit for a job like yours. They typically drill through basement walls, concrete floors and ceilings, and other concrete and stone surfaces to create pathways for pipes and anchor holes for railings.

For a single hole in one rock, going to a such a company makes the most sense. But if you need holes in multiple rocks or if the rock you want to use is too big to transport, you could explore other options, including renting a drill and a bit and doing the work yourself, assuming you’re relatively handy and strong.

Many home improvement stores rent a Hilti core drill rig that can be used either in a stand, like a drill press or as a handheld tool, which is how you’d probably use it for a job like yours.

If you were drilling only a shallow hole, there are ways to rig up a water-cooling system for a diamond bit without having to get a drill that feeds water into the bit. For example, you could press plumber’s putty into a ring around the area and fill that with water to create a puddle around the bit. But because you want to drill 8 inches deep, this won’t work. The tip would be dry.

Hammer drills and rotary hammers (also known as rotary hammer drills) can also drill through some types of rock, and they’re great for making holes in concrete. Both types provide a hammering action that helps the bit work. But quartz is much harder than many rocks, and it often has a structure that consists of “a bunch of crystals pushed together,” said Ethan Currier, an artist who often drills into stone to create garden artwork. “You’d risk blowing it up” if you tried to drill through quartz with a tool that delivers a hammering action, he said.

Or, taking an entirely different approach, you could decide to forgo trying to drill into stone and instead create a stonelike anchor made of concrete. Mold the concrete around a piece of PVC plastic pipe that will become a sleeve your birdhouse-supporting pipe can slip through. PVC piping is rated by its inside diameter, but test first to decide whether your pipe will slip easily through ¾-inch PVC, or whether 1-inch diameter pipe would work better. Tape over the ends of the sleeve pipe before you add the concrete mixture so you don’t accidentally plug the pipe or get gunk inside.

For a mold, find a cheap large bowl and invert it. A cardboard box also works as long as you support the outside, perhaps with sand piled into a larger box. Spray the mold with cooking oil first so you can slip out the concrete or peel away the cardboard later. Embed bits of broken china or tile for a decorative effect if you wish. Buy almost any kind of concrete mix and check the label to make sure it’s suitable for pouring into a mold as deep as you’re using.

To make sure you buy enough concrete mix, multiply the length, width and height of your mold in inches to determine its volume in square inches. If you’re using a bowl or other round shape, measure across the rim from the center to the edge to get the radius. Multiply that by itself three times, then by 3.14 (pi) and, or take the no-math option and use an online calculator; find one by typing “volume of half a sphere” into a web search engine.

Whatever anchor you’re using, be careful not to pound the support pipe far into the ground where you might hit a buried water or power line. To check on whether that’s an issue, call 811 or file an online request via the “homeowner” section of three days before you want to do the installation.

TribLIVE commenting policy

You are solely responsible for your comments and by using you agree to our Terms of Service.

We moderate comments. Our goal is to provide substantive commentary for a general readership. By screening submissions, we provide a space where readers can share intelligent and informed commentary that enhances the quality of our news and information.

While most comments will be posted if they are on-topic and not abusive, moderating decisions are subjective. We will make them as carefully and consistently as we can. Because of the volume of reader comments, we cannot review individual moderation decisions with readers.

We value thoughtful comments representing a range of views that make their point quickly and politely. We make an effort to protect discussions from repeated comments either by the same reader or different readers

We follow the same standards for taste as the daily newspaper. A few things we won't tolerate: personal attacks, obscenity, vulgarity, profanity (including expletives and letters followed by dashes), commercial promotion, impersonations, incoherence, proselytizing and SHOUTING. Don't include URLs to Web sites.

We do not edit comments. They are either approved or deleted. We reserve the right to edit a comment that is quoted or excerpted in an article. In this case, we may fix spelling and punctuation.

We welcome strong opinions and criticism of our work, but we don't want comments to become bogged down with discussions of our policies and we will moderate accordingly.

We appreciate it when readers and people quoted in articles or blog posts point out errors of fact or emphasis and will investigate all assertions. But these suggestions should be sent via e-mail. To avoid distracting other readers, we won't publish comments that suggest a correction. Instead, corrections will be made in a blog post or in an article.