Schott 90 Rods

[Irene]

I've got a bunch of Schott 90 clear rods and was wondering if anyone has ever used these for fusing with BE 90. I searched the internet but found only one thing. Arrow Springs says to NOT use these with BE but they did not say why. These were given to me by another fuser and I haven't tried anything with them yet. I was hoping someone had some experience with them. And yes, I will do a stress test for sure, but I think stories and experiences are great ways to learn too.

If you think they should not be used with BE, I'd be curious to learn why. I don't know much about Schott at all and could not find anything on their site regarding this.

Many thanks for any help.

[Brad Walker]

The Schott rods should work for flameworking, but will not be compatible for fusing.

There's more to compatibility than coefficient of expansion. The two glasses have different viscosities. Since flameworking is less demanding in terms of compatibility than fusing, you can usually get away with using Schott rods with Bullseye rods when flameworking, but most likely they won't work together for fusing.

The kind of stress test that flameworkers do won't necessarily tell you if the two glasses would work for fusing. You'd need to do a compatibility test for fusing to know for sure.

[Irene]

Interesting! Thanks very much, Brad. It's just what I needed!

[beninfl]

You can always dump them on lampworketc.com's garage sale forum, it's pretty busy there for this type of glass they'd sell in an hour if priced reasonably.

[Irene]

Thanks, BeninFL!

[Bert Weiss]

COE is only one of the factors that make glasses compatible, viscosity is another. PPG Starphire is around 90 COE and not even close to compatible with Bullseye tested compatibles. On the other hand the COE of Youghiogheny EZ fuse has quite a different from the COE than the PPG float it is compatible with.

The other factor with a COE number is that it is calculated around 300ºF, and the published numbers are a loose average. This means little relative to fusing compatibility. Compatible glass is compatible.

[Brad Walker]

The other factor with a COE number is that it is calculated around 300ºF, and the published numbers are a loose average.

300 C.

[Bert Weiss]

The other factor with a COE number is that it is calculated around 300ºF, and the published numbers are a loose average.

300 C.

still pretty cool...
(first time I ever used an emoticon)

[Irene]

Thanks, guys! I think this stuff is really neat to know. Explains a lot!

Appreciate all the info!

[KaCe]

So you are working!? I miss you. Glad to hear you're doing some glass. Would love to spend some time yakking... my insomnia keeps me up; then I sleep late. I'll give you a call tomorrow, or you can call me.