How can you cut rectangles in glass?

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Forum topic by tefinn posted 02-10-2012 04:06 AM 10582 views 0 times favorited 14 replies Add to Favorites Watch
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1222 posts in 2677 days

02-10-2012 04:06 AM

Topic tags/keywords: glass mirror cutting question picture frame

I’ld like to make a frame-in-frame picture collage with the two frames seperated by a couple inches of unbroken glass or mirror (8×10 center, surrounded by glass/mirror, surrounded by 4×6 multiples). This requires cutting a rectangular hole in the center of the glass to inset the inner frame.

How can I cut the center opening in the glass/mirror?

If I try to cut the opening with a wheel cutter I get fractures in the corners that travel out to the edges like on a windshield. I’m getting tired of wasting glass. My only thought was to use a glass bit and drill at each corner and then “connect the dots”.

Any other thoughts or ideas?

-- Tom Finnigan - Measures? We don't need no stinking measures! - Hmm, maybe thats why my project pieces don't fit.

14 replies so far

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3261 posts in 2915 days

#1 posted 02-10-2012 04:59 AM

I think you are correct when you say drill the corners. Then you can sand it….maybe you want that and you are done. Otherwise there is no place for the break to stop.

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joey bealis

177 posts in 2746 days

#2 posted 02-10-2012 05:02 AM

Use a diamond cutting wheel on a dremel. Even drilling the corners would still be just luck to get it to do right.


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2139 posts in 3954 days

#3 posted 02-10-2012 01:00 PM

This is something that is out of my league, but I’ll offer a suggestion anyway…lol. Have you tried a circle cutter? I would start by trying to cut a circle out of the rectangle, one that touches at least two of the rectangles sides. Then, repeat with smaller circles in the remaining waste. This would eventually give you triangles within the border of the rectangle that you should be able to score and snap.

Glass cutting is something I do not do, and have never tried that… Just offering an idea.

Good luck,


-- As iron sharpens iron, so one man sharpens another. (Proverbs 27:17) †

View DrSteve's profile


34 posts in 3089 days

#4 posted 02-10-2012 01:07 PM

Probably not what you want to hear, but unless you are looking to become proficient at glass cutting I would look into having someone else do it. We have a glass shop locally who has years of experience and that it what they do. I bring the project in and they do the rest. Easy as that. No cleaning up broken glass shards from my floor either.


Do what you do best, contract out the rest

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388 posts in 2570 days

#5 posted 02-10-2012 03:43 PM

Perhaps look in the yellow pages under water jet cutting and see if any of the companies can do glass.


-- OK, who's the wise guy that shrunk the plywood?

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4032 posts in 3211 days

#6 posted 02-10-2012 04:01 PM

A waterjet machine can cut anything you want, but at $80 per hour it may not be what you want either.
Drilling the corners with a diamond drill makes sense.
Then scribe hole to hole and also corner to corner; then rap the center of the cross.

Or, as Steve said, take it to a glass shop. My local shop always surprises me how cheap they are.

View jmos's profile


905 posts in 2609 days

#7 posted 02-10-2012 06:20 PM

I made stained glass for many years as a hobby. I’ve never tried what you are attempting, but it will not be easy. As you’ve discovered, glass tends to “run,” any crack will continue to travel. If you score the glass first, and the score isn’t too curvy, you can get the glass to run along the curve. However, if the curve is too tight, the crack will go off the score in an unpredictable manner. Concentrating stresses is you enemy.

I would try drilling out the corners as you propose, then scoring from hole to hole. If you have a simple glass cutter it has the scoring wheel (it’s not a cutting wheel) on one end and a ball on the other. Once you have the straight line scored, flip the glass over and use the ball and tap along the score; do this hard enough to get the glass to crack along the score, but not hard enough to chip or shatter the glass. If you lucky you will get the glass to crack through along the entire length of the score. Repeat on the other 3 sides.

If you do get the center out, do not try to square off the corners too much. This will provide a place for stresses to concentrate, and the glass might crack due to some incidental movement. You can sand the glass to smooth things out, but I think you’ll still end up with a rather ragged looking opening.

Having said all that, you might want to consider using stained glass techniques to make a glass frame. It sounds like you’ll have all straight cuts, so it will be really easy cutting. I prefer the copper foil method (Tiffany) as opposed to lead came. If you want to try it, let me know and we can talk. It’s not too hard to do. According to your profile your in south Jersey, as am I. I’d be happy to help you out.

-- John

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3261 posts in 2915 days

#8 posted 02-10-2012 08:07 PM

I had another thought. My in-laws built a house and in the master bathroom she had a large mirror installed behind the sinks. On each end of the vanity there was a short wall so she had a mirror installed there also. they cut the holes in the mirror for light switch boxes then they cut mirror switch cover plates out of mirror. This was all holes (rectangles) cut in glass. It can be done and it can be done well and it never cracked.

View tefinn's profile


1222 posts in 2677 days

#9 posted 02-11-2012 04:44 AM

Thanks for all the replies. I know this is going to be a hard one!

jmos - I’ve done stained glass myself in the past and you are correct it is a scoring wheel (it was late and I was tired when I wrote the OP last night). I’ve already made frames with stained glass before. My idea for this one would be to have words or designs printed on or glued to the clear glass to give the illusion of them “floating” between the inner and outer wood frames. I’m going to try drilling the corners and score hole to hole. I think crank49 had a good idea with scoring the diagonals also. I dont need sharp corners because the edges of the frames will cover the glass by at least 1/2 inch and I can shape the inside of the rabbits to fit the glass.

If I can get the cut made I’ll post the method that worked!
Thanks again all!

-- Tom Finnigan - Measures? We don't need no stinking measures! - Hmm, maybe thats why my project pieces don't fit.

View mtenterprises's profile


933 posts in 2933 days

#10 posted 02-11-2012 05:49 PM

Have you tried scoring your square then scoring corner to corner diaginals then tapping the x in the middle?

-- See pictures on Flickr - And visit my Facebook page -

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#11 posted 02-11-2012 07:25 PM

Another thought completely would be to use lexan or plexiglass.

-- TJ - Perryville, Missouri

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933 posts in 2933 days

#12 posted 02-12-2012 02:49 PM

FreshSawDust, Now thats the best idea. Mask it off drill a hole and go at it with the scrollsaw. 2, or more, heads are better than one.

-- See pictures on Flickr - And visit my Facebook page -

View BradB's profile


3 posts in 3137 days

#13 posted 02-13-2012 12:30 AM

I hate to burst your bubble. I am a professional glass artist. What you want to do cannot be done with tools the woodworker will have. It has to be sandblasted by someone who knows what they are doing. DO NOT use the scroll saw. That is very dangerous. It will shatter and possibly explode from the friction. Glass is NOT cut it is scored or ground down with a special water cooled saw called a Ring Saw. Taurus Ring Saw if you want to google it. Phone a glass company and see what they have at hand or call a stained glass store and see if they will do it with a ring saw. Mirror is very fragile and thin. Especially if you are using mirror tiles. Call a pro!

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1222 posts in 2677 days

#14 posted 02-13-2012 02:55 AM

mtenterprises – I’ve tried scoring the sides and then corner to corner. The glass will still radiate fractures at the corners. Thats why I’m going to try drilling at the corners before scoring. I checked with a local glass shop and they said this should work fine. If not they can do it for a reasonable price. I just haven’t had the time to try it out yet so I don’t know for sure if it will work for me.

FreshSawDust – I thought about using one of those, however they don’t have the look that glass does. They have that plastic look that real glass just doesn’t have. If I was making them for retail I probably would use one of them just for time savings and cost, but thanks for the suggestion.

BradB – Nobodys suggesting cutting glass with a scrollsaw. If you read the posts, it was suggested to use lexan or plexiglass as an alteranative to glass and cut with a scrollsaw. This CAN be done.

-- Tom Finnigan - Measures? We don't need no stinking measures! - Hmm, maybe thats why my project pieces don't fit.

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