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Cutting Opal glasses

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Cutting Opal glasses

Postby cjalexander » Thu Dec 03, 2009 4:23 pm

I've been cutting and fusing for over 4 years, and lately have been having major problems with several of the opal glasses. No matter how good the score sounds, and no matter which direction I try to cut the glass or which of my 3 Toyo cutters I use, I could not get a single good break out of a half sheet of Opaque White. Same with a half sheet of Periwinkle, and also one of Gold Purple. Very frustrating and very expensive.

Other glass fusing friends have expressed the same problems. Is there anyone who might be able to offer some advice, suggestions, help? It would be sincerely appreciated.

Thanks!

Connie
Sequim, WA
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Re: Cutting Opal glasses

Postby marykaynitchie » Thu Dec 03, 2009 4:32 pm

Hi Connie,

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.

Mary Kay

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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Re: Cutting Opal glasses

Postby tommckay » Fri Dec 11, 2009 8:58 pm

Cold in Scotland!. I am Scottish in fact only came to Northwest just over a year ago. As I write it is 16℉ outside which is minus 9 in real money!! I don't think I ever experienced minus 9 ℃ all the year I lived in Bonnie Scotland. It's like the myth it always rains in Seattle. OK so we don't get 100℉ in summer but most years neither does Washington. Still we love it here, it's just like home!! Only thing wrong it's full of people with funny accents, I think they're American!
Sorry this should be about glass but you started it!!
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Re: Cutting Opal glasses

Postby Vicki Floyd Willhite » Wed Jan 20, 2010 10:27 am

Some friends and I get together every winter to put together Christmas projects in my little studio here in the Portland, Oregon area. Since the studio is only heated when it is occupied it can get pretty chilly in there and, of course, that is where all the glass is stored. We have run into the same cutting problem with the opals (and on rare occasions some of the transparent as well) that you've discussed here. We had suspected that the temperature of the glass might have been a contributing factor but were never sure. Thanks for the verification. We'll be sure to give the studio more time to come up to temperature in the future and will warm the glass before attempting to cut.

Thanks for sharing!
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Re: Cutting Opal glasses

Postby Lani McGregor » Wed Jan 20, 2010 2:45 pm

vitalspark wrote:Cold in Scotland!. I am Scottish in fact only came to Northwest just over a year ago. As I write it is 16℉ outside which is minus 9 in real money!! I don't think I ever experienced minus 9 ℃ all the year I lived in Bonnie Scotland. It's like the myth it always rains in Seattle. OK so we don't get 100℉ in summer but most years neither does Washington. Still we love it here, it's just like home!! Only thing wrong it's full of people with funny accents, I think they're American!
Sorry this should be about glass but you started it!!


Vitalspark,

Feel free to divert the tech talk to Bonnie Scotland and its brilliant dreich weather anytime!

-L
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Re: Cutting Opal glasses

Postby johnreeves » Wed Jan 20, 2010 4:56 pm

I have also had intermittent bad breaks with opalescent glass, and I now suspect that it may have been due to a cold New Mexico shop and too much pressure, trying for the old zip of clear. This post has been very helpful; thanks to everyone.

John Reeves
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Re: Cutting Opal glasses

Postby Dolores » Thu Jan 21, 2010 8:51 am

Ditto, opal cutting problems here, especially 3mm dense white and royal purple. I live in Southern California where it never gets very cold, so I don't believe that that is a issue. My best solution has been to make the "important" cuts on my Revolution saw (gives it a nice clean edge too). Many times I broke a score and had it fall apart where not intended. I just assumed that certain colors had their quirks and found a way around it.

DOLORES
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Re: Cutting Opal glasses

Postby jestersbaubles » Thu Jan 21, 2010 6:45 pm

You said you tried three different cutters, but are all three older? Could just be the wear & tear on the cutting head.

If I am having trouble, many times I will turn the glass over and tap it with the cutter along the score line. That usually helps tremendously. My work room is in the basement, and I'm in Utah, so we have cold winters. It is usually in the low to mid 60s.

You probably know these things, but I have no idea what everyone's experience level is :)

Regards,

Dana W.

www.jestersbaubles.com
Dana Worley Fused Glass Designs
dba Jester's Baubles
http://www.jestersbaubles.com
http://www.jestersbaubles.blogspot.com
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Re: Cutting Opal glasses

Postby s. klein » Fri Jan 22, 2010 4:46 pm

Even here in (usually) sunny CA it gets a bit cold in the winter. My studio is in the mid 40's. I find that this does affect cutting glass. Yesterday and today I had to cut alot of white strips. I started out having a few problems with the cold glass. I went to my nearby Wal Mart and bought $16 an extra large heating pad. Placed 2 half sheet on the bottom and 2 on the top. turned it on to medium. In about 20 mins I had warm glass that felt good to the hand and cut just like summer glass. Now all I neeed is an official BE log cover for the pad!
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Re: Cutting Opal glasses

Postby Lani McGregor » Fri Jan 22, 2010 5:16 pm

Thanks, Steve! What's next, you gonna be knitting tea-cozies for the frit jars?

Oh, I forgot, you can't knit. :lol:

- Lani
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