Maybe what she needs is bead release that makes it easier to remove the beads from the mandrel. I have read that the blue sludge is not as easy to get the beads off the mandrels as the dark grey sludge with the graphite in it. Even easier is a dark grey graphite release like KRAG Mudd. If you are making large beads, you really need to have a bead release you don't have to fight with.

Donna, have you ever tried KRAG Mudd?? If not, PM me and I will send you a little sample of mine.

I use Mama G's (and love it), and I keep it fairly thin. I have noticed, though, that as it dries it does take on a thicker look and feel

Real or imagined?

I'm using a new batch of blue sludge and haven't seen any cracking issues at all with it. I've had it for about 6 weeks now. I got super blue sludge and dip n go. No problems with either. I made a few thinner beads to try and see if they would break. I got no breaks.

[Q


Which ingredient in bead release could have the expansion capabilities?[/quote]

h2o is the only one I can think of
even after the release is dry it contains water until it reaches 212 *
the boiling point at which time it is steam












.

h2o is the only one I can think of
even after the release is dry it contains water until it reaches 212 *
the boiling point at which time it is steam

.[/quote]

That makes sense.

I wonder if some bead releases hold temperature better than others. And therefore one may be more forgiving than others on that score.

Different bead releases seem to require different thickness coatings as well. Maybe that plays into it somehow.

I've been teaching beadmaking for over 10 years now and I am pretty definite that this is a shocked bead issue.

The question is not just how thin your beads are, it is how long you keep them in the press without reheating them and how long you reheat the glass after the bead has been in contact with the metal.
The thinner the bead, the faster it will lose heat so the faster you need to put it back in the flame. Even if most of the bead stays hot enough, the thinner layer that is over the mandrel hole may have been shocked (i.e. the glass got below the temp where it is elastic enough to handle stress) and if that part of the bead is not taken back to a soft state, the stress will not be erased and the bead will crack because it will have been shocked.
I would advise you to press quickly, go back in the flame immediately and reheat carfeull along the mandrel on both sides. If the pressing is not what you want, do it in stages until you are sure that you get the timing right. Does that make sense ?

Anne I agree !
It makes sense that heat is the problem.

I only offered the illustrate to show that after a mandrel is in the flame for a few seconds it is impossible for it to cause a bead to crack.

I would also look at your clear. I have used Lauscha forever and love it. Some years ago I had a problem with certain rods of clear, but not all of it. Something to think about anyway.

I was thinking the same thing. We have so many brands of clear out there now and there is no way of knowing if they are truly compatible with the brand(s) of 104 COE we choose to mix it with. They only thing we can hope to do is keep up with reports of compatibility issues. It seems like every time I read about cracking beads, it's from mixing all these lines (brands) of glass together.

If encasing with clear glass, I say use DH with DH, Effetre with Effetre, and CiM with CiM, just some examples here. But of course, there are no guarantees with using glass in the same lines either.

Incompatibility cracks usually aren't straight, right?

Incompatibility cracks are usually not going to break in half straight down the mandrel. Donna's beads have a thermal shock problem rather than incompatibility, I'm pretty sure.

As far as any kind of cracking goes, I have read dozens of threads over the last 11 years that I have been lampworking and many of them are referring to clear encasing and incompatibility cracks. That's why everyone needs to be careful with clear and do a little research and take notes on what colors and particular brand combinations other artists have found to be problematic.

Incompatibility cracks are very different from what Donna has. I've had problems with a Lauscha clear years ago and the beads cracked 6 months later, all at the same time and with a webbing pattern to the cracks. Thankfully I still had all of them !