Putting beads back on mandrel after annealing.

[killerbeedz1]

Okay I've got a couple of beads that need to go back into the kiln due to hairline cracks (just a few). However, I've tried to do this so many times in the past and it never works out. I dip the mandrel, put the bead on the mandrel, clean off around the bead hole edges with a little brush. Wait for the bead release to dry, then run the bead under a little bit of water and with a little brush clean off the surface of the bead just in case any bead release got on it. So my little procedure doesn't work. Everytime I do this as careful as I might be, there's a little residue of bead release somewhere on the bead that I obviously can't see. A little film if you will. This makes the bead even worse. If there is a little bead release on the bead and I heat it up, I have to trash the bead. Whereas before, with those little hairline fractures, I could have at least worn it or give it to my sister. So what I'm looking for here is to see what everyone else does when they have to put the bead back into the flame to correct little imperfections to make it saleable.

[LavenderCreek]

I do it pretty much how you described except I use smaller mandrels and I put them right into the kiln after wiping the ends with a papertowel. No drying time, they will dry in the kiln. I haven't had any problems so far, knock on wood

[Abacus Beads]

I don't take my beads off the mandrel to anneal them so if they have any cracks etc. I can just put them back in the kiln . I save them so I can run a bunch of them at a time. For me it cuts out a lot of extra steps and time. I guess the trick is to examin each one very close before I take them off the mandrel
Liz R

[killerbeedz1]

Liz:

I don't take my beads off the mandrel to anneal them either. They are made and put immediately in the kiln. The cracks are discovered after they are taken out of the kiln, taken off the mandrel and cleaned. I do examine them, but sometimes I'll miss a tiny crack here or there and I won't see them until I try to photograph them or look at them through a magnifying lens. Or they may crack afterwards. Sometimes a day or two afterwards.

[BarbaraB]

If the bead is off the mandrel, I use a smaller mandrel that is dipped and dry and slip the bead on. After it is has heated up in the kiln and I wave it in the back of the flame to condition it in the flame, I wrap a little glass around the mandrel on each side of the bead so it won't slide off in my lap.

I usually try to repair it before I remove it from the mandrel.

[MaureenKennedy]

I am confused about what you are trying to accomplish? If a bead has cracks, the mere fact of re-introducing them into a kiln and raising temperature to annealing temp will not heal cracks. The only way to do that is to get bead hot in kiln and then re-introduce it back into the flame and have the flame melt the cracks to heal them and then re-anneal the bead.

Having said that, I don't take my beads off the mandrel and if I see I need to heal anything, I wash the bead off in the faucet and use a nail scrubber brush to clean bead so any film around dots and that are washed clean.

[melissabeads]

I was wondering the same thing Maureen. I guess I have always been afraid of trying to fix a bead. Any crackers go into the fish bowl..he he..

If this is a really a sound way of fixing a crack..I would love to hear more.

[Emily]

No, you can't repair a crack by just heating it in the kiln, unless you heat it up to the point where the glass melts and runs together (at which point it would very likely drip right off the mandrel). I think what Patsy's talking about, though, is getting a bead ready to put back into the flame and heal. If you weren't lucky enough to discover the flaw while it was still on the mandrel with reasonably intact bead release, you have to put it back on a mandrel, put it in the kiln, bring it up to temperature, and carefully transfer it to the flame without burning yourself or cracking the bead. If you get it that far, you can re-work it and fix the problem, but getting that far can be a challenge.

[Toni Lutman]

I've never done it with a cracked bead, but I did this with one that was dropped on the driveway and chipped near the hole. It was a pain to get back on a mandrel with out a bunch of mess on it, but I was able to do it, and mended the chipped area. It was an encased bead, so I just needed to add a little clear glass.

[Otter's Flame]

Call me lazy but I just make a new bead. I have repaired cracks before but I just found it to be more trouble than it was worth. Fortunately I have lost few beads to cracks. Even if it is a bead I totally love and it cracks, I just make a new one....yes I am lazy.

[Kevan]

I have successfully done this twice. Every other time I have tried it the bead blew apart.

[ukiacat]

I put the bead back on the mandrel, let the bead release dry and then put it into the kiln the next time I turn the kiln on. I then introduce the bead into the very end of my flame and slowly move it up into real heat. The mandrel almost always burns me when I take it out of the kiln. The heat travels up the mandrel to my fingers. I have to be careful not to let the plunged flowers move under the encasing while I get it hot enough to repair the crack....I ruined a couple beads with movement. The real problem comes though, when it turns out that the crack was caused by glass that did not want to be encased. There are a couple colors that just crack all over again. At least I learned to avoid those colors as a base. So, remember to check the bead closely when/if you think you were successful. Sooner or later it may just crack again.

Good Luck
J

[ziggys]

Hm....I remember reading and printing out a post on the ISBG forum that was called something like "playing god" healing your glass creations. It told how to heat parts up in the kiln and re-attach them. It was more for sculpture work though. So that might not be of any help. But it's about re-introducing glass to the flame so maybe? I still have the article if you want more info.

But the other day I was talking to Flametree Glass asking about the latest best clear glass.
She said they stopped carrying Lauscha because they had a class making huge beads, encased with that and they all cracked. She said to "heal" cracked beads take them up to 1020 degrees. Then the normal annealing process I would assume.
Maybe that would work for you. And no extra work with the flame again!

The other thing that has been making me think is the film you speak of. I can't help but wonder if it's coming from something else. Are you sure it's bead release? It just sounds odd that you would have so much trouble with it after doing all that work! What else could cause a film on beads?
Do you ever batch anneal? Is that the schedule you use to re--introduce them to the flame? If so do batch annealed beads ever have a film? Just thinking out loud.
I tend to agree with Otter's Flame though. Since I don't have many, ( thank god, knock wood) I just make another. But if I had a lot I would definatly try to do what Flametree does.
FWIW,
Angela

[Magicfire]

Hi Patsy:

I'm not sure why you are having the problem with the bead release...I just wanted to say that I have done this lots of times and generally have good results with it. I take a mandrel that already has dry bead release on it, and rub some of the release off so there is a thinner coating. Then I try to coax the bead on to the mandrel without breaking the rest of the release. Sometimes I have to try 2 or 3 different mandrels before I get it on there well enough so it will stay in place.

I don't use wet bead release. I'm not saying that wouldn't work; I've just never tried it. I wipe the bead off really well with a dry cloth before I put it in the kiln.

Another thing I do to help keep myself from getting burned: I've discovered that if I dunk the end or ends of the mandrel in my water jar, it instantly cools off the mandrel so I can hold it.

So I grab the mandrel from the kiln with my cross-locking tweezers, dunk and then start warming the bead up in the end of the flame. I make beads in the middle of the mandrel, so I dunk one end, grab that end with my hand and then dunk the other end. "Normal" people could dunk the one end of the mandrel if you are holding it with tweezers near the bead.

Some beads, however, are doomed. I'm never quite sure why, but some beads I try to heal just won't stay healed, I guess because of incompatibility.

Some beads are worth the trouble, though, like a bead I made in a Michael Barley class that had a thermal crack!

Good luck!
-Patti

[Dasi]

See post #14 about the mandrel...

http://www.lampworketc.com/forums/sh...ad.php?t=10151

[killerbeedz1]

Emily is correct in what I am trying to accomplish. The reason I wanted to repair a couple of beads is because they were large and very time consuming and one had a couple of tiny cracks the other had one. I took Teresa's advice above and put the beads on a smaller mandrel. Before putting them on the mandrel though I cleaned them with a toothbrush and some soapy water (just in case there was some scum I couldn't see). (I should say at this point the reason there might be scum on the bead is because I put them into a glass filled with water when I take them out of the kiln and some release falls off into the water.) Anyway I put the bead back on the mandrel and I let them dry because they were big heavy beads. After drying I took a small paint brush and some clean water and further cleaned around the holes (again afraid there's some bead release I can't see). Heated up the kiln to 950 slowly introduced into the kiln. Took them both to the torch and I'll be damned (there's the freaking scum by the bead hole). I tried to stay away from it and did so on one, but on the other bead I had to get into that area to repair one of the smaller cracks. The scum is bead release that as hard as I try (and believe me I cleaned the area with water and brush by the mandrel hole several times to avoid this) I can't get around this. On the bead I was able to avoid the scum - looks great, but the other not. I think when I have to do this again, I will try the suggestion above and put the bead back on a dry mandrel. That has got to work better than what I just decribed to you. Anyway, thanks everyone for your help.

[opportunity-shop]

Originally Posted by BarbaraB

If the bead is off the mandrel, I use a smaller mandrel that is dipped and dry and slip the bead on. After it is has heated up in the kiln and I wave it in the back of the flame to condition it in the flame, I wrap a little glass around the mandrel on each side of the bead so it won't slide off in my lap.

This is what I do. Reintroduce the bead high in the flame. Barb