Glass cutting - Mirror to be more specific

[David May 01]

For the guru's of great and powerful knowledge.

I am building a built in with a mirror with a round / curved top. I am currently working on the frame for the mirror (woodworking part) and now will need to cut the mirror to fit.
I picked up two tall arched top mirrors,(came as a package and just in case I screw the first one up ) and now have to trim off the bottom.

Over the course of my life I have experimented with the standard glass cutters, however, I have not been taught the art of snapping the glass.

It should be fairly straight forward, as it is a straight cut mid length of the mirror and only 20 inches across.

Can the experienced in the crew guide me in attmpting this, or should I just take it to a glass shop with my line drawn. I am not worried about the bad luck thang, as I have plenty of that, and another piece of broken mirror will not affect me at all.

My goal is to succeed the first time, and to hang the other mirror on the back of the bedroom door. For my wife of course.

[Tom Klass]

If the glass cutter is sharp once you score the glass it should snap in your hands. Just give the cut off a little up lift, another way would be to put a pencil under the score from both edges and push down on the cut off gently. Don't go over your score line with the cutter once you did your original score. For the cutter you can use a little kerosene or glass cutting oil for a lubricant, this also helps with better cut. I'm no expert just my .02 from working at a hardware store in my younger days.
Tom

[frank shic]

i recommend taking it to a professional glass shop. it'll take them ten minutes to score the mirror, break it and then sand the edges. those glass cutters that you can purchase at home depot will not cut thick mirror well.

[Bill Huber]

If you can't use pocket screws like everyone else uses around here I would take to the pros.:D :D :D

I had some glass cut and finished a year or so ago and it didn't cost all that much to get it done and it was really nice looking edges when they were finished.

So I vote for the glass shop.

[Grant Wilkinson]

Between framing my wife's art and framing mirrors for all the friends that see my wife's framed art, I've done more of this than I would like.

As others have said, only score once. Lube your cutter with a bit of kerosene or Pam if you don't have kerosene. Apply firm steady pressure to the cutter and run all the way across the mirror. Don't stop in the middle to scratch your nose or anything. Make sure that you start over the edge at the start and that you run right off the mirror at the other end.
Then just bring the score line to the edge of your table and sharply push down.
If you need to cut off small strips, the pencil idea mentioned previously is good.

[Grant Lasson]

David,

I found that the mirror coating affected the snapping of the glass. If left unscored, it snapped in unpredictable directions. I had trouble scoring the glass effectively through the coating with one pass. If you're in a hurry to get the job done right, you might be ahead to just take it to a glass shop.

[David DeCristoforo]

I'm with Frank...let a "pro" cut it for you. One thing I can tell you for sure...don't let me do it! My success rate with cutting glass is around .01%. Me and glass just don't seem to get along very well.....

[David May 01]

Ok, Thanks to the all knowing. I think I will call the local glass shop and tell them I am coming. I am sure my wife does not want to hear the tirade if I screw it up. Then I get a rectangular piece too.

David

[Jerry Spencer Mings]

Much to my supprise a $0.99 diamond glass cutter did the trick for me. Cut right through the reflective backing. A bit of round over with a cheap diamond wheel (HF) in a rotary tool and Bob's your uncle.

YMMV

[frank shic]

My attempt with a home depot glass cutter didn't go nearly as well - ragged edges all over the place. i'll admit that i don't cut glass as often as i cut wood!

[Lee Schierer]

When we cut down the large mirror in our bathroom into smaller pieces to fit into the new medicine cabinet, I took the mirror to the local glass shop. I think they charged less than a dollar a cut and I also got the scrap glass so I had a mirror for another project a year later.

[Joe Mioux]

I love cutting glass, I never cut a mirror, but once you get the technique down, you will want to play with curves etc.

Part of the technique is holding the cutter properly and just a consistent score across the glass. don't stop and ease up at the end. Let the cutter and your hand drop away from the end of the glass.

I like to slightly lift the glass and then "snap-through" the scored edge on a side of a flat bench.

Joe