Anatomy and Physiology of the Lampwork Bead

Don't let the title scare you off. This has to be way more interesting than that cat I had to dissect in college...right?
On every lampworker's table should be a cup/can/pot/non meltable container of some sort filled with water. This is basic safety (along with a fire extinguisher close by!) but also serves a practical purpose. Sometimes beads turn out so ugly, even my mother would hate them and there is no saving such ugliness. Why bother annealing the monstrosity? Dunk it into the water and listen to the satisfying sizzle and pop and all proof that I ever made an ugly bead shatter to pieces.
Over the weekend I decided to clean the cup of the 50 or so mandrels that had collected in there over the course of several months. Most were empty of beads. However, this bead clung onto the mandrel for dear life:
Just the day before, I had a long conversation about fat mandrels and bead release on my facebook page with beady friends and non beady friends. The non beady friends were confused as to what a fat mandrel was...a band? Another name to call someone driving like a jerk?

The conversation was still fresh in my mind when I removed this bead from the mandrel (the steel rod the hot molton glass is wound around and leaves a hole. See below:

This particular bead wasn't a rejected fugly. It was actually a bead I was making for a friend to give to a friend and had almost completed when I let it get a little too cold. When I reintroduced it to the flame, all hell broke loose and it cracked in half. Sometimes you can save those. This one couldn't because the end popped off and took half the bead release.
Bead release is the white stuff you see on the steel mandrel. It is what keeps the bead from being permanently fused to the mandrel and a nice ornament for your plants. It is also the white stuff you see in what was supposed to be the hole in the cracked bead.

Lampwork beads generally crack for two reasons. The first is thermal cracking. It cools too quickly and the molecules are unable to align properly and it causes stress for the glass. The bead usually cracks in half. This is why it's important for you to buy beads that have been annealed (cooled very slowly in a controlled manner) in a kiln. If a bead has been properly annealed, it should bounce on tile or concrete, but not crack apart. It WILL have little chips of glass break off where it landed, because it IS glass after all...

The 2nd reason beads crack is because the glass in incompatible with another glass used. This results in spider web breaks where the incompatible glass meets. This is why lampworkers and fusers talk about using COE compatible tested glass.

So, back to the bead. I thought it might be interesting to all of you to see the middle. It's clear. Why? There are 3 main reasons lampworkers use clear in the middle and encase it with other colors. It just so happens I used clear as the core for all 3 of those reasons.

#1-the lampworker plans on using a premium (meaning expensive) color on the exterior. Making a clear core is a way to stretch the premium glass to last longer and cost less. The opaque pale yellow on this bead is the premium color. I don't want to waste any of it in the core where you won't even see it.

#2-the lampworker wants to use dense transparent colors and needs to lighten it up with a clear core. This bead I used a violet, intense blue and turquoise (not shown). If I had just done those colors solid, it would have looked black...or at least close to black

#3-opaque colors get very runny and soupy when super heated. Using a transparent core prevents the opaque color from dripping onto the table. The technique used in this bead to create the surface color requires a super hot flame.

Here was the second try bead where I made sure to pay better attention to keeping it nice and toasty.

Hope this was at least a little better than dissection a cat...


Ginga Squid

Wow - the finished one is amazing!I'm now going to use the term 'mandrel' for people I see driving like jerks!


Pretty nice post. I just stumbled upon your weblog and wished
to say that I've really enjoyed surfing around your blog posts.
In any case I'll be subscribing to your rss feed and I hope you write again soon!


Very informative!! I love to learn about the bead making process, and you are a very good teacher! Someday I'll have to give it a try. The finished product is beautiful! As usual! :)

Jennifer Cameron

Thanks ladies. The friend liked the bead, which was the most important thing. Anytime you happen to be in Indiana, I will be happy to teach you how to make beads.

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