Frit-Happens !

Lampwork => Lampworking Tip n Tricks => Topic started by: Jane C ♫ on December 16, 2013, 09:31:23 AM

Title: Cubic Zirconia - multiple inclusions query
Post by: Jane C ♫ on December 16, 2013, 09:31:23 AM
Hi!

Is there a limit to the number of Cubic Zirconia I could add to a bead before it becomes too stressed?

Are you supposed to encase them or can you leave the tops open to the air?

Thanks!
Title: Re: Cubic Zirconia - multiple inclusions query
Post by: mel on December 16, 2013, 05:09:58 PM
I think that you could get quite a lot into a bead without it cracking, although I personally would avoid having them cheek by jowl over large parts of the bead surface. I never encase them, but I make sure that I poke them well in so that the glass just begins to flow around the edge to hold them in. Don't forget that they have 2 different sides too, the flat side faces outwards and the more pointy side goes into the bead.
I glue them onto the tips of knackered mandrels which I have filed flat, then it's just a case of spot heating the bead and a confident poke.

I have never had a bead stressed due to CZ. There is more stress for the bead-maker than the bead!
Title: Re: Cubic Zirconia - multiple inclusions query
Post by: Redhotsal on December 16, 2013, 05:44:15 PM
I think it depends on size. I had some .8mm CZs which I quite happily encased in clear and at any level within the glass and although you can see stress around them (with a polariser) they have survived quite well. However, I also have some 1.2mm CZz which can crack the surrounding glass. I have mine very close to the surface and I encase with a thin dot of clear. They don't like to be "half-encased" - in other words - either encase the thing fully (so that all the CZ is beneath glass) or have it on the surface of the glass like Mel says. I really think size is the major issue.
Title: Re: Cubic Zirconia - multiple inclusions query
Post by: Jane C ♫ on December 16, 2013, 05:45:48 PM
Thanks Mel and Sal - that's really helpful.

I'd done a bit of an internet search and found the PVA glue / mandrel trick.
Have ordered some 2mm cz so will see how I get on with them.
I'll try them encased / not and see what happens!