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bethanybeads
2010-09-07, 9:01pm
Hi everyone,
This is my first time posting, although I've used the site many times. I made an amazing underwater bead that cracked (argh!!). The crack appears to be due to uneven heating/letting the bead get too cold (??) even though I thought I was really careful. Is there any way to fix this bead by heating it up really hot in the kiln? ...Or any other way? I'm (hopefully) attaching pics.
Thanks!
http://i73.photobucket.com/albums/i209/bethanylemasters/IMG_0637.jpg
http://i73.photobucket.com/albums/i209/bethanylemasters/IMG_0636.jpg

ewdb
2010-09-07, 9:54pm
yup, i've done it several times but it's not easy: don't remove bead from mandrel, put cold bead in kiln, ramp up slooooowwwlllyyy no more than 200F/hr to preheat in the kiln to about 980F. let bead sit at max temp for at least an hour - you want the bead to be evenly heated through to the core

then... here's the tricky part (so if you really love this bead maybe practice with another cold bead first)... cool the mandrel with a damp cloth and remove the bead. begin waving it faaarrr out in your flame slowly wafting/twirling the bead in and out of the flame to slowly reheat it evenly.

moving slowly is the key - the idea is to slowly reheat the bead through to the core without cracking it so watch the layers of glass and as each layer heats to glowing you can move a few mm closer to the normal working range. you'll know if you're moving too fast as the bead will likely explode, lol...

if nothing else consider this great practice in heat control... :-) Good luck!

PerfectDeb
2010-09-07, 11:09pm
wow really nice bead - worth giving it a go, good luck

theglasszone
2010-09-08, 12:03am
yup, i've done it several times but it's not easy: don't remove bead from mandrel, put cold bead in kiln, ramp up slooooowwwlllyyy no more than 200F/hr to preheat in the kiln to about 980F. let bead sit at max temp for at least an hour - you want the bead to be evenly heated through to the core

then... here's the tricky part (so if you really love this bead maybe practice with another cold bead first)... cool the mandrel with a damp cloth and remove the bead. begin waving it faaarrr out in your flame slowly wafting/twirling the bead in and out of the flame to slowly reheat it evenly.

moving slowly is the key - the idea is to slowly reheat the bead through to the core without cracking it so watch the layers of glass and as each layer heats to glowing you can move a few mm closer to the normal working range. you'll know if you're moving too fast as the bead will likely explode, lol...

if nothing else consider this great practice in heat control... :-) Good luck!

Evelyn...please forgive me for adding to your awesome explanation...but I feel this should be clarified since the original poster is trying this for the first time:

"...then... here's the tricky part (so if you really love this bead maybe practice with another cold bead first)... cool the (exposed portion/handle part of the) mandrel with a damp cloth and remove the bead (still on the mandrel!) from the kiln. begin waving it faaarrr out in your flame slowly wafting/twirling the bead in and out of the flame to slowly reheat it evenly."

One additional suggestion:

While slowing moving the bead in the flame, try to avoid hitting the cracked area directly with the flame in the beginning of the re-heat. Flip the bead one side (where there is NO crack) and waft and wave it in the flame. Flip the bead 'round to the other side and continue to waft and waive it in the flame. Once these two uncracked sides begin to show signs of glowing, then slowly introduce the cracked areas into the flame. This will also better your chances of preventing it from cracking further.

:)

Yeah?

Seasoned Soul
2010-09-08, 3:52am
Most valuable information. Thanks everyone for this info.:smile:

Ofilia
2010-09-08, 4:04am
I suggest, take advantage of the perfect middle split, and let it be two cabs! Then go make more aquarium beads. Then again, it could be good practice on reheating an old bead, I just like the cab idea more..... especially when half the work is already done for you;-)!

houptdavid
2010-09-08, 11:01am
I'm with Ofilia make cabs!

Laura B
2010-09-08, 11:20am
... "...then... here's the tricky part (so if you really love this bead maybe practice with another cold bead first)... cool the (exposed portion/handle part of the) mandrel with a damp cloth and remove the bead (still on the mandrel!) from the kiln. begin waving it faaarrr out in your flame slowly wafting/twirling the bead in and out of the flame to slowly reheat it evenly."...

You rock... I was totally trying to figure out how she's going to cool the mandrel down, remove the bead, and then wave it through a flame. Ouch!

Kevan
2010-09-08, 11:25am
The problem with fixing these kinds of cracks is that if you do get the bead reheated they tend to divide along the crack when they begin to melt. You have to be really really careful and go really really slowly when you reintroduce it to the flame. When it's end to end like that it tends to just split open further. It's easier if it's only partly cracked. I've fixed a lot of cracked beads and this is the hardest kind of crack to fix. But what's to lose?

squid
2010-09-08, 1:20pm
I would probably make cabs too. Kevan is right - the edges of the crack will retract from each other when you heat it. If your clear is thick enough, it may be ok.

Elizabeth Beads
2010-09-08, 2:46pm
Even if you manage to heal the crack, you will most likely have an optical line where the crack was. I think the risk of having half of a 900 degree bead go flying or worse explode outweighs the benefit of a repair. Chalk it up to experience and make another.

I know it hurts. I have a few of those half beads lying around myself, or worse yet, the ones where I picked up and used a clear short of the wrong CoE right as I was finishing a bead.

one hot beader
2010-09-08, 3:11pm
Make it into a pendant for yourself, with a fixed bail so that only the good side shows.

That's what I'm going to do with my coral reef bead I just made that cracked.

yellowbird
2010-09-08, 3:18pm
I suggest, take advantage of the perfect middle split, and let it be two cabs! Then go make more aquarium beads. Then again, it could be good practice on reheating an old bead, I just like the cab idea more..... especially when half the work is already done for you;-)!

YES

ewdb
2010-09-08, 5:37pm
Evelyn...please forgive me for adding to your awesome explanation...but I feel this should be clarified since the original poster is trying this for the first time:

"...then... here's the tricky part (so if you really love this bead maybe practice with another cold bead first)... cool the (exposed portion/handle part of the) mandrel with a damp cloth and remove the bead (still on the mandrel!) from the kiln. begin waving it faaarrr out in your flame slowly wafting/twirling the bead in and out of the flame to slowly reheat it evenly."

One additional suggestion:

While slowing moving the bead in the flame, try to avoid hitting the cracked area directly with the flame in the beginning of the re-heat. Flip the bead one side (where there is NO crack) and waft and wave it in the flame. Flip the bead 'round to the other side and continue to waft and waive it in the flame. Once these two uncracked sides begin to show signs of glowing, then slowly introduce the cracked areas into the flame. This will also better your chances of preventing it from cracking further.

:)

Yeah?

thanks for clarifying! i forget details sometimes... :-D

and for those saying give up/make cabs - it all depends on the bead. some i'll just dunk cuz it's not worth it - but if i've worked 1-1.5+hrs on a single bead and it cracks right near the end you bet i'm gonna try to save it!