I checked with our technicians (who also frequently teach glass cutting and get a lot of practice around here) and here is what they suggest:
If you've had success cutting this glass in the past and are suddenly struggling, one possibility is that your glass may be cold – the weather has recently gotten much colder, and cold glass, particularly opal glass, is much more difficult to cut. One of our techs had the same problem the first time he went to teach in Scotland (in the warm middle of summer, ha!). He put the glass in front of the heater for about an hour and suddenly cutting was very easy again.
That would be a place to start. If that rings no bells (because you are storing your glass and working with it in a heated space) then we’ll need to dig deeper.
Here are some suggestions that I am sure you already know about, but let me mention them anyway. Ample cutting oil (or mineral spirits) and a carbide wheel are necessities to cut opal glasses. Also, unlike transparent colors, opal glass creates very little sound when scoring at the correct pressure. The cutter doesn't "zip" in the consistent and audible way that transparent colors do. So if someone is getting a good zipping sound on their opal glass, then we suspect there is too much pressure on the cutter.
If those are not the issues, then sometimes we have solved cutting problems with opalescents (particularly in production uses) by analyzing the sequence of cuts from the sheet. Sometimes the sequence and placement of scores can be changed to make the glass cut successfully.
Let me know if any of these seems worth a try.
PS: If others have advice for cutting opal glasses successfully, please feel free to chime in!
Mary Kay Nitchie
Bullseye Glass Co.
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