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Cutting the basics tutorial


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Cutting glass is not a difficult task with quality tools, a few basic techniques, some practice and confidence along the way.

There is three steps involved: the score, the snap and grinding.
Scoring is making a "scratch" across the glass, it has to be continuous, and it usually starts and ends on the edge of the glass you are working on.

The Snap is a fracture you cause that follows along the score line. The glass will part company cleanly when a fracture is made correctly. There are many ways of achieving a particular cut and being familiar with what technique to use, is what you'll find out very soon. Practice and experience will show you the rest.

Grinding is a step that some people miss out.... DOH. I never miss this even if the shape is already tidy after cutting. Grinding at very least removes sharp edges which makes them safer to handle.
The primary purpose of grinding is to remove extra glass left over on the cut edges.
This finishing work makes a huge difference in the quality of your final product, believe me, it is worth the effort. Grinding also helps with shaving off small amounts of unwanted glass and does a far better job at this than grozing pliers. Trust me, spending money on a grinder is worth the investment..!!

Your work bench needs a few important features.

A large and solid flat surface, preferably topped with wood and finished in white
Most excellent lighting
A carpeted area on the floor below
It is best to stand while working, so a bench at a comfortable standing height is ideal.

For cutting curves and circles I recommend you have a small table set up, one that you can step all around. This will make curve cutting so much easier.
Watch the following video clip and you'll understand why....

Youtube Video clip
Make a cutting table

Hand tools for cutting glass

The cutter
There are many available out there but only one class that "cuts the mustard"....!
Buy the very best you can afford, believe me it is worth it, your results and confidence will show!
Get a self oiler like those illustrated below. There's really no point in using cheepo's, don't buy them, they do not save you money in the long run!
Illustrated below is 3 variations of handle. You'll need to choose for yourself the cutter that best suits your hand size and cutting style. Try them out at the glass supply store before you buy one!!
The cutting heads will survive intensive use for up to 12 months providing you look after it by keeping it clean, dry and well oiled. Do not abuse it with heavy handedness, i.e. pressing too hard while scoring. You'll hear a distinct small sound when the cutter is scoring, listen for it. The louder it is tells you that you may be pressing too hard.

a few cutters available

The Grozing pliers
These pliers have jaws designed specifically for holding and nibbling glass. Do not use any old pliers laying around, they will not perform like the proper ones!
Grozing pliers close at the tips, the jaws are specifically angled so that they hold and nibble glass correctly. They have tough rows of rasping teeth that enable them to nibble away glass on the edge.
The two pliers illustrated below serve different purposes: the red pair are general purpose, holding and nibbling. The blue pair have a very narrow jaw and are used exclusively to nibble glass back into tight concave curves. These pliers also have spring loaded handles that hold the jaws open, a feature most helpful during nibbling.
When buying pliers, ask for knowledgable advice at the supply store. Buy two pairs of general purpose and a pair of narrow nibblers. These tools are essential, using them well on a specific task will be covered and demonstrated shortly.

grozing pliers

Ruler and T-square
Not any old ruler or square will do. They must be quality tools, made from hardwood or steel.
You'll need a short 12 inch and a long 36 in. A short T-square and possibly a long one too. I have a good selection of rulers and squares, one for any occasion a?!
I also have a T-squares wide enough to reach across a full sheet of stained glass, it is called a "Glass Crop" They are all "battle scared" but as long as the edges are not damaged, it's all good.... :-)

rulers and T-squares

The glass grinder
Some say that grinding is an optional extra however, if you want very accurate fitting lines that facilitate a professional finish, you are going to need a grinder. Everything I cut gets a pass on the grinder. The only exceptions are straight lined pieces that have no edge errors.
There are a variety of grinding heads available for a machine, check out your options at the supply store. I go for a course head generally.
The heads are expensive so look after it! Always use it with the water feed working (never dry) and do not press hard with your glass.

OK, lets get cutting.

We're going to start with the easiest cuts, the straight line. Tools needed are just a cutter, metal ruler or a T-square. Initially you'd best start with lots of practise on some 3mm clear window glass.
It is cheap to get and it cuts like butter so you can make it easy for yourself..... :-)

Don't accidently choose toughened glass to practise with...!!

Hey,... why won't it snap easy??.... give it some more force mate.... you know you want to.....!!
Then SMASH, it shatters to a thousand bits..... !! DOH it must have been toughened glass?!
Just as well you are wearing safety goggles a?!
YEP.... :-0

OK, I'm not going to write endless instructions, there is just so much to say....
Instead, watch the following video. View the video a few times until you've got the idea, then practise cutting with each technique many times until it's really easy for you.
Only move onto the next episode when you've mastered your current one... Yes?!

Youtube Video Episode 5
Cutting a straight line

Next Tutorial Cutting curved shapes.

www.karalstudio.com/glass/stained-glass-tutorials/cutting basics.html