If you are wanting to cut glass tubing, use a glass cutter or file to create a scratch where you want the break, then pull the two halves of the glass towards yourself, and the glass tubing should...
glass brakes easily because, well it's glass and it isn't very strong so that's why. Glass is hard so it is strong, so glass doesn't brake easily.
no they dont its normal
Yes.
I'm assuming dose means does, but one way to break glass is to drop it or hit it with something hard
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Scoring and Breaking Straight Lines in Stained Glass
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