I got several questions and emails about how to cut mirror, so I thought I’d show you a quick little how-to. It’s important that we briefly pause to discuss the molecular dynamics of glass, and touch on the debate over whether it’s an amorphous solid or a viscous liquid and —
Just kidding. I don’t care.
What I do care about is turning these giant sheets of glass we found on craigslist for free into an octagon, or whatever shape we may need.
Materials You’ll Need
- Glass cleaner
- Glass cutter (Something like this one if you’re looking for low cost, or like this if you’re looking for fancy.)
- Optional: Glass cutter fluid (this kind goes with the fancy glass cutter) or kerosene
- Safety goggles. Yeah, I said it.
Brief interlude about safety goggles
Andy occasionally watches these incredibly dry and snooze-inducing woodworking shows. On every episode, the host pauses before he uses his first power tool, looks deeply into the camera and says:
“Now remember, there’s no more important safety rule than wearing these, your safety glasses.”
–But I don’t buy it. Is there really NO more important safety rule than that? What about: “Do not attempt to clip fingernails with a miter saw” or perhaps: “remove any blindfolds before using a power tool?” I’d like to submit to you that there ARE more important safety rules than wearing your safety glasses. But you should still wear them. And maybe gloves. The end.
* * *
1. Prep the glass
2. Measure and mark your cut line
There’s probably a professional marking device of some kind, but we used sharpie. ‘Cause we’re all about just getting the job done with minimal fancy extras. White crayon can work too.
We clamped down a straight-edge right along that line so we could run the cutter against it.
3. Score the line
At this point, technically you should lubricate the mirror with kerosene or glass cutting fluid. Some glass cutters are self-lubricating (like the one I linked to above) so you’d just prep the cutter and you’d be set.
Our glass cutter is not self-lubricating, but you want to know a secret? We didn’t use any fluid. And we never have. The fluid just helps your blade last a little longer, but if you don’t use any, the glass-cutting police might never even know.
After you’ve lubricated the line (or not), run the glass cutter along your line one good time, pressing down hard enough to hear an awful screeching sound.
It will leave a scored line that looks like this:
4. Break the mirror down the scored line
This part is either amazing or terrifying, depending on whether you’re the kind of person who likes to ride rollercoasters and eat raw cookie dough or not. Prop up a board or something under the mirror on one side of the scored line.
Then gently press down on the mirror until it breaks along the line you just scored.
It’s nerve-wracking but also kind of awesome. Pass the raw cookie dough.
5. Optional: Sand the edge
Our mirror went inside a frame and the edges will never be seen or touched by a human again, so we didn’t do anything to the raw edge, but you can sand it down or apply a mirror edge sealant or just clear fingernail polish if you’d like.
* * *
It’s really a simple, straightforward process as long as you have the right tools, and as long as you wear your safety goggles like a winner.
Have you ever cut glass? Where do you fall in the mirror-as-viscous-solid-or-liquid controversy? What would YOU say is the most important safety rule?
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