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tammydownunder
12-17-2005, 05:38 PM
I know this has been done to death, but my question is twofold. I was using Hotline but the beads would release too easily when I did any kind of manipulation. I bought the purple pfiffle and have the exact opposite problem. Lately I've been playing with a new lentil press, dicroic glass and copper green hand pulled glass. The beads look fantastic and appear not to have cracks but when I remove them from the mandrels after much struggle, they crack. I hate wasting expensive supplies and time only to turn them into rubbish. Any suggestions?

Tammy

Henrywashere
12-18-2005, 02:53 AM
Hi Tammy,
I have very limited experience with lampworking - but I am very experienced in cracked and broken beads lol. I discovered that my vermiculite was not hot enough that I was cooling the beads in. If you are using a kiln and this is happening I have no idea. Regarding the bead release I was having all amount of trouble using a specific brand - I found a recipe for making your own on the Aussie forum that works a treat - but it did stir up quite a ruction on the forum because of the ingredients. I figure if you use a mask etc and take necessary precautions to guard you health while making it the benefits of the release far outway the negatives.
Christine
aufolkart@optusnet.com.au

Luthien
12-18-2005, 05:53 AM
Are these kiln annealed? If not that is probably the problem. Round beads do ok in vermiculite most of the time, but once you begin pressing and doing alot of shaping you increase the amount of stress in the bead and they break much more easily. Before I got my kiln I would say that 1 in every 5 lentils would break, usually during cleaning, or sometimes just by putting them in water.

I don't know anything about dicroic glass but maybe there is a compatability problem with the other glass you are using? I do know that when I mixed different COE's, before I had a kiln, those beads would also crack fairly often.

If these are annealed beads then it might be that you aren't re-heating them enough after you press them. Are they cracking down the middle, or in a spiderweb pattern?

Can't help you with bead release, I still haven't found one that I like.

Daisy May
12-18-2005, 02:16 PM
Like Teressa says it could be any number of different things which are making your beads crack.What you need to do is exclude a few things by experimenting. Try using the same combination of glass in a simple round bead, so you can see if the glass is compatible, Make it about the same size as your lentil. If that cracks then its sounds like it might be the glass. Another thing you could do is make a the same bead your making now with your old bead release and see what happens. Sometimes if you put too much stress on a bead while making it, the bead release will crack just a bit in the middle of the mandrel, where you dont see it. The glass sticks and then you have trouble getting the bead off. Sometimes when your having trouble getting a bead off, you can put it in the freezer for a while. Thats supposed to shrink the steel a bit and make the bead come off easier. Also is this a new shape for you, Have you successfully made this bead before using different glass or different bead release. If your using a base of copper green, you could be getting it too hot. Sometimes if you overheat opaques, it makes it difficult to get the bead off the mandrel. I know this isnt an answer for you but maybe this will help you figure it out, What about the annealing process, if this is a new shape it could be that you are not evenly reheating the bead before cooling. Try to exclude a few things and then post with some of the info we dont have. Good Luck