The Framers Forum

I'm not bad at cutting glass, but only small sizes, up to 20" x 16". Bigger than that, I get it cut at a local glass merchant. I watch them do it, and they cut very large pieces of glass in exactly the same way that I do. Lay it on a padded table, score it with what looks to be exactly the same glass cutter as I use (Toyo) and then lift it slightly and break it apart with a finger & thumb pressure. Except when they do it, they barely have to look at the glass for it to snap, whereas I have to apply some pressure, and sometimes quite a lot of pressure.

What are they doing differently? Are they using a heavier pressure when they score the glass so that the score goes deeper?

I suspect it could be how much pressure you apply when scoring. I was taught that you know when you have scored the glass correctly when it sound like tearing a piece of silk fabric as you run your cutter along the glass!

Also, it probably looks easier when you see a full sheet being cut because as you lift the sheet of glass, its own weight takes over and the glass sheet just falls apart.... it that makes sense?

A good tip is to clean the glass first, so that the cutter doesn't skid over a greasy bit. Then make sure your cutter isn't worn out. I keep my cutters soaking in an inch of white spirit, and shake this off a bit before cutting. This lubricates the wheel. Best thing to do is take scrap piece of glass and spend a while scoring and scoring until you get a good feel for the cut.

Both the above advise is good, I use an oiled filled cutter, but I always check it and even drop a bit of oil on the wheel, then score a couple bits of off cuts to check it's okay, when I cut a full sheet, I score, put down the cutter and t-square, then fingers and thumb either side of the score mark, then in one movement lift and flick of the wrists to break the score line, after all this time it's done subconscious, don't really think about it. What you need to do is watch how you cut the smaller bits of glass, how you hold the cutter, the angle you hold it, and the angle when you are doing the score all the way down the t-square (it needs to be the same all the way down the cut) . The hand cutter is like a good fountain pen, it gets worn into the way you use it, so don't let anybody else use it, A) they will not be able to use it right, B) they could bugger it up for you.

Also it could be down to the glass, or the way you store it, I store mine on a rack I made, 3ft wide by 4ft high frame work covered in chipboard, with a base, so when you look from the side it look like the letter L but the back leaning back about 10 degrees, so the glass is put on the rack leaning back, but is supported across the whole surface, if you store glass leaning back not supported, so it has a curve to it, in other words has a stress already in the glass, so when you lay it flat, and score it, then try to snap it, the two stress work against each other and your score like will either shatter or the line will go off course

as with everything, practise makes perfect,

In order to avoid the amount of pressure you mention in your OP try easing the scored sheet over the edge of you bench and "open" the cut by giving a firm tap on the underside of the cut with the back of your glass cutter. You will see the cut start to run and much less pressure is required using the finger and thumb method

When I cut a full size sheet I prefer to swing the sheet around on the bench until the scored line is parallel to the edge of the bench and around 2" on the bench, then gentle equal and downwards pressure with both hands works a treat. That way you are using the weight of the glass to work in your favour

Very little to add to the excellent advice you have received so far except always wear the correct clothing (gloves/boots) as has been said a drop of oil on the tip of the cutter and a professional cutter with a swivel head is essential when drawing down log cuts.

I keep a old cutter for slicing up my off cuts.

Peter

These are all very helpful suggestions which have given me some pointers, thank you

It's mostly a matter of confidence. Those guys at the glass co. do it all day and could do it without looking.

If you are having to lean on the cutter to get a score then you need a new cutter. Not all cutters are created equal and it's
worth paying the extra to get a decent one. A wet with White Spirit (as mentioned) helps a lot.

You'll get so you can tell a good score. It 'sings' rather than crunches. If you have a ragged line with tiny shards shooting off then that is not good.

Lion VAPOURMAX glass cutting fluid
- penetrates deep into the cut, keeping it ‘warm’, which helps improve cut quality

- lubricates the wheel and axle for reduced wear and flushes the glass dust

- perfect viscosity for hand cutters

- evaporates quickly, leaving minimal residue, which helps speed glass cleaning. Low odour


Works with all cutters, with or without a reservoir in the handle.

If you use a cutter without a reservoir, we suggest a glass jar with screw on lid. Pour some Lion Vapourmax onto a felt pad in the bottom. Stand the cutter in there when in use. When not in use, lay the cutter to one side and screw the lid on.

When I started cutting glass I just could not get on with it, then I had someone come to my workshop to teach me and straight away he said the problem was with my cutter which I had only purchased a few weeks before. I then purchased a new Fletcher Gold cutter and straight away there was a massive improvement. I was also using a wooden T-square and changed to one from Wessex Pictures and as soon as I did that I was fine at cutting glass as the cutter ran down it much more smoothly.

Once I changed the cutter I found I needed very little pressure. You know when it's working fine just by the sound of the cut. If the cut is good the glass also separates along the score line easily with very little effort.

When I started using glass I order 6 sheets to be delivered from a local company. They were 6' x 4'. Bad Idea.
I was working from home then. Not a big house.

So I thought I would slice the sheets in two to make them more manageable. Good Idea. In theory.....

I had bought a 6-wheel cutter. Cheap one. Long story short, I ended up with a lot of triangular pieces.

Learned two things: Don't use cheap cutters and kitchen floors are not as flat as they seem.

All really good points, many thanks

I feel a bit spoiled with this one, I've only ever used an Excallibur 5000 to cut glass.

Need to give it a try doing it properly one day...

Hello! Watch a good video tutorial on glass cutting.