Cutting Glass and Mirror
You will need:
· A FIRST AID KIT: Have a First Aid Kit handy, with gauze and some good tape.
· GLOVES: Gloves, preferably ones that glass can’t cut through.
· PROTECTIVE EYEWERE: Safety Eyewear is a good idea it can’t hurt.
· A GLASS CUTTER: Use best quality you can afford, the cheap ones are useless.
· A STRAIGHT EDGE: A selection of Tee-Squares are best.
· A WORK BENCH/TABLE: The Work Bench or Table will need to be as level as possible.
In case you did not already know, Mirror is Glass, with the silver coating sprayed on one side.
Mirror is manufactured in sheets of about 8 x 10Ft. it will then be cut to more manageable sizes by the glass merchant and it comes in weights of 2, 3, 4, 6mm it is unlikely that you will find mirror in imperial weights nowadays as most mirror comes out of China and the production equipment in China is generally metric equipment.
The thickness of mirror and glass is described as the weight of the glass as glass and mirror was in times gone by sold by weight.
Cutting glass or mirror is a little like cutting wallboard/sheetrock with a razor blade, cut the outside paper and bend it, it breaks where you cut the paper.
I learned to cut glass on a bench and have never mastered the use of my wall cutter for this task, to me it is frightening to have glass or mirror at face level, I know many of you have mastered the wall cutter and if you are confortable with that you will not need Tee-Squares or straight edges, I’m directing this post in the way I cut glass and mirror.
The work bench NEEDS to be as level (flat) as possible otherwise you will get a crocket cut line and the glass/mirror will not snap properly, I have covered my bench with carpet this helps to take the unevenness out of the bench, special benches for cutting glass can be purchased I think they would cost from about $2500 to $20.000 depending on what you need.
Lesson 1: Have a very flat workbench or forget going any further, you will NOT succeed in cutting heavy mirror or glass without a good flat bench covered with a carpet or if you can get it the special felt that glass suppliers use on their benched.
Straight edges as glass is very smooth it is unlikely you will keep a straight edge from slipping, you could try covering one side of your straight edge with very fine wet and dry sandpaper it will reduce the likelihood of it slipping also the straight edge needs to be a strong one like the ones you have in the US for cutting sheetrock, light straight edges will flex and give an uneven cut. I have three Tee-Squares 30”, 48” and 72” these are quality Tee-Squares for the glass industry, these allow for very straight score lines on the glass/mirror that allows for good snap lines.
Lesson 2: Have a selection of Tee-Squares
Don’t skimp on your glasscutter, the cheap ones are useless for anyone that is serious about cutting glass/mirror. When you score the glass/mirror it makes a distinctive sound, so you must listen to it (turn off the CD player) if the sound skips so then did your score line, try filling in the skipped part before moving your Tee-Square, try a few practice cuts first. 2mm or 1/8” should be allowed on the measured size for the thickness of the head of the glasscutter.
Lesson 3: Get a good glasscutter and allow 2mm for the thickness of the head of the cutter.
Hold your Tee-Square firmly where you want to cut the glass/mirror to cut (mirror glass side up). The glasscutter scratches the outside surface of the glass/mirror. Hang the glass over the edge of the bench or slide the Tee-Square under the glass/mirror on the score line (scratched line) and bend down. That won’t work if you only cutting off a little, at least try cutting of 2” waste or more, hang your 2” over the edge of the bench after you have scored the glass/mirror and tap on the underside directly under the score with the blunt end of your glass cutter, tap lightly until you see it break just a little, line the score back up with the edge of the table then right at the little break bend the 2” down almost as if your twisting off the 2””. If you are cutting 4mm ¼” glass/mirror or more it will be allot harder to bend, you will have to tap the underside allot harder also, I would recommend you buy a pair of breaking pliers they are made specifically for breaking glass/mirror along the score line. The other way as I said is to slide the Tee-Square under the glass/mirror this is a bit difficult with mirror, as you cannot see the score line
Lesson 4: Be careful and practice first, allow enough waste for an accurate break.
Use gloves and protective eyewear and have a first aid kit to hand (you should have a first aid kit already if not you are being silly and possibly breaking the law).
Please be very careful the people who introduced me to glass/mirror cutting had a combined 300+ years of experience between them.
Another tip, if you buy your glass/mirror in the big sheets and do not have a straight edge big enough to cut it with, cut a 3” strip free hand off the sheet and use the straight side as a straight edge.
If safety is a concern for mirrors you could use the slide door mirrors that are used in bedrooms, this mirror has a safety backing, you cut and snap it in the way described above then you need to cut the safety backing with a razor blade or burn it apart but that’s for another lesson.
Finally beware there is a relationship between the size of glass/mirror to weight that you can safely use, again someone gave me the details but unfortunately I have miss placed the chart.
Take care.
