Drilling Hole in a Glass Mirror

[Ross Richardson]

I have a question on what and how to drill a hole in a glass bathroom mirror. I have to replace the light fixtures and they are different than what I have. These were the light fixtures in place when we went to full length vanity mirrors and the installer made access holes for the wire and the attachment screws. And, guess what, the attachment screws will be in a different place this time.

What is there to use. I have Googled some and found out that there are diamond drills out there. How are they used. I have to do this job right the first time or I get to have a new mirror installed.

Ross

[Jeff Wisnia]

These, or the same type from another source, will do the job if you have a steady hand and take your time.

They work for me.

HTH,

Jeff

[Jerry G.]

You can get diamond drills at most of the large hardware centres. It is best to properly mount the mirror and use a drill press. As the drill is turning you should use some high temperature silicon lubricant to help reduce the heat from friction. This type of work is best done with experience. It is best to have the feel for this, or you have a very good chance to scrap your mirror. The drill bits have a high wear factor, so you may need more than one for the job, depending on the number of holes. The instructions with the drill bit may indicate something about its wear factor, or expected use.

The best solution is to precisely mark where you want the holes, and have the proper size. Take the mirror over to a place that does glass work. They will only charge a few dollars for the job.

[3rd eye]

This is easy. Take it to a glass shop & have them do it for you.

If it's glued on the wall have them come to you. Some things are just not worth trying to do yourself.

[ceraboy]

Ross

If you can, find an old broken mirror and do a test run before you try it on the real thing. Of course the test may dull a cheap carbide bit to the point it will not work well on the real piece. While drilling through the glass should not be too problematic, you must be real careful with the mirrored coating on the back. This is typically a thin foil or sprayed metallic film. Either way it is very fragile and if you are not careful you can peel off large pieces beyond the mounting coverage of the fixture. Taping it might help, but this was more problematic for me than drilling through the glass itself. If you do use a diamiond drill bit use plenty of water to clear out the debris and keep the bit cool. Also, do a search of this newsgroup, I remember this exact same topic a year or so ago.

[Oren]

Test on the current mirror if you like, but the dangers of being seriously hurt is still a factor. I agree with others - call a glass and mirror company.

Oren "My doctor says I have a malformed public-duty gland and a natural deficiency in moral fiber, and that I am therefore excused from saving Universes."

[Big Al]

You can use a brass flathead screw and valve grinding compound. Just don't let the glass get hot. Mount the screw by the threads in an electric drill. Run it slow in a puddle of compound. Press down and wait. When you feel it quit cutting, lift the screw and push the compound back in the right place. It's not fast but it works. I'd make a test hole in some scrap glass just to get the feel of it.

Al

[Tom McQuinn]

I saw my father drill a hole in glass this way probably 35 years ago. He used a drill press, a wooden dowel rod, and valve grinding compound.

Tom

[BocesLib]

Anyone ever try using a grinding bit used on rotozips. Works GREAT on hard glazed tile, it might work on glass too.

[Ross Richardson]

Thanks for all the replies. From the searches I have done, this seems like a art to do. I must tell everyone that the mirror is already mounted to the wall, so I really do not want to remove it. The suggestion of having someone come to the house is a good suggestion. I bookmarked the Harborfreight drill bits and for the price might buy them and get some old glass to practice on. For the reflective surface I figured there would be some flaking near the hole, but at first that was not a concern since I would be covering it with the light fixtures by several inches. But the one responder makes be wonder how far this might migrate. I'll have to think about this one. Everything that I did read says it is a slow process, the diamond bits do wear, and should use a drill press. Since the mirror is mounted the drill press is out of the question. I have some more thinking to do.

Aga> Anyone ever try using a grinding bit used on