A

Some people can cut glass in the cold, but most of us have trouble when the temperature drops.  That could be because our hands tremble a bit in the cold, making it more difficult to do a good score.

But there could be other reasons for the trouble. Start by checking your cutter’s cutting head.  The little wheel should move freely.  If it doesn’t add a few drops of mineral spirits or light oil and make sure it moves easily.

In addition, some glasses, such as streakies, whites, and textured sheets, are harder to cut. Take extra care with these glasses.

Even worse, some sheets of glass are just plain evil! They might have been poorly annealed by the manufacturer or maybe the kiln gods weren’t happy on the day they were made. For those sheets, it helps if you put them back in the kiln and fire to around 1000F/540C, then re-anneal.

But it does help to let pieces warm up a bit before cutting, if only so you can warm up, too.