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I use Nichrome high temp wire inclusions alot in my fusing. Usually it works fine but sometimes I have trouble with a small crack occurring at the tip of the wire. I have tried slow soaks, slow ramp down, longer anneal soak, thicker glass, everything I can think of. I am frustrated, and wonder if others have learned about this?

Use the thinnest you can find. It is strong after firing, unlike copper

I use the nichrome wire in fused glass sculptures. I usually use 17 Ga, and sometimes twist several strands together. I have been doing this for years and it works fine 2 out of 3 times. I just dont understand why sometimes it doesnt work. There must be others who use wire and have experience with this. There is a reason why it cracks sometimes and not others, I just dont know it. The wee crack starts right at the tip of the wire. I think it is something in the cool down process. Any input would be of value.

Got a picture? Sounds like the twisted wire is fairly thick. How close to the edge of the glass are you going? What's your schedule?

You may want to look at your glass under a polarizing lens and light. Sometimes the crack is just the final manifestation of stress. I don't, off the top of my head, know the thermal expansion rate of nichrome, but it could be that nichrome doesn't really "fit" your glass. If it doesn't and there's a large enough mass of wire compared to the glass, it could be stressed all along the length and only cracking where the stress exceeds a certain level.

The problem with that is that, sometime in the future, the uncracked pieces might be subjected to uneven heating/cooling and expand/contract just enough to push the stress over into a fracture.

I use 17 gauge kanthal wire and have excellant results when the ends of each leg meet together inside the glass, like in a circle or oval.

Gee, I use much smaller gauges, but mostly stainless steel wire. 27 and 23 gauge. I have some nichrome that looks maybe smaller than 23. I've always used SS, but quite a few years ago I bought the nichrome, since everyone seemed to use it. I tried it, and it seemed so stiff and hard to work, so I put it away. Funny, this year I pulled it out again, and it bent so easily. I may just be crazy. I used to bend the ends of the wire or curve them in to keep them from pulling out, but I've never had a problem with straight legs coming out -- they stick tight in the glass.