nichrome wire inclusion

[Deb Brown]

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?

[Stephen Richard]

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

[Deb Brown]

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.

[Jeanne]

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?

[Morganica]

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.

[Mark Hall]

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.

[Mark Kemp]

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.