In June artist Steve Klein was teaching in La Granja, Spain. By July he had led a professional artist-in-residence program at the Pilchuck Glass School in Washington State. It’s August now and he’s co-teaching a workshop with Kaffe Fassett at North Lands Creative Glass here in Scotland. This fall he’ll be at Bezalel Academy in Jerusalem.

Steve claims to have bad knees. I can’t imagine how much faster he’d move with good ones.

read more

I expected to be blogging about Teaching Artists again today, but a recent kerfuffle over on a popular Internet glass forum caught my attention yesterday. Since it’s about one of Bullseye’s kids – aka products – I feel like I need to get all Mommy-like and charge into the playground to defend my brat.

The thread started out peacefully enough with one of Bob Leatherbarrow’s students lamenting the discontinuation of 0313 Dense White, one of our more than a dozen varieties of white glass.  So who needs this much white in their life?


The infamous “ring around the collar” caused by the collision of lead, sulfur and heat in Bob Leatherbarrow’s “Pebble Boulder Roll-Up”.

read more

Levenson grenade 2

Last week I got an email notice of a new podcast that promised to “Expand Your Mind and Explode Outworn Beliefs!” read more

It’s a weird business climate today. On the one hand, anything you write from inside a for-profit business is going to be met with skepticism. On the other hand, a lot of people still buy into commercial messages without question.

When will she quit??!?? Soon. Soon. Meanwhile, here’s a laboratory test glass with a measured COE of 89 (sorry, the 90 COE lab glass that we’d tested previously has been discontinued). According to popular understanding this glass should be within the range of expansion mismatch for a COE 90 glass (plus or minus 1 COE point). Not.

I’ve been ranting for weeks now about the misunderstanding of the Coefficient of Expansion within the studio glass community. Steve from Glasgow made the brilliant if obvious point in a comment to my April 11 posting that we’ll never get rid of this use of the COE as a shorthand equation for compatibility until it’s replaced with something else.
read more

After dragging you tediously through how we test for compatibility, what the COE is, how it is tested and what it does NOT tell us, the obvious question is: So, who ever suggested that matching COEs could identify compatibility in the first place?

We did.

GETTING OUT FROM UNDER SOME SERIOUSLY OLD INFORMATION. Written almost 25 years ago by my partner Dan and his then-partner Boyce, Glass Fusing Book One was the first – and is still the most definitive – book ever written on the subject of kilnforming. Today, even Annie is too smart not to dig out from under that old story.

Yes, this entire mess started at Bullseye. We made a mistake. We (actually, it was Dan Schwoerer and Boyce Lundstrom. I wasn’t here at the time, Your Honor) believed that matching the LEC would insure that glasses “fit” when fired together.
read more

READY, FIRE, AIM. Before you start kilnforming on this scale, you might want to understand what you’re doing.

I was about to unmask the fools who started the COE mess when I got a private email asking me why I was making such a fuss about compatibility standards when – by our own admission – Bullseye’s are likely tighter than they need to be.

First of all, that wasn’t quite the point of my rant, but I’ll take a momentary detour here to explain why this stuff matters…
read more

I’ve got a brilliant vet. She’s coming to our home to help Ed “pass over”. I wish there were a glass doctor who’d do the same thing for the sick old myth of the COE.

Fat chance. This misunderstanding about compatibility and the Coefficient of Expansion has been around for longer than many people have been fusing. They were raised on it. Sadly, it may be around forever, mucking with basic technical information in our field and making it harder for users to solve problems when they occur.

We’ve never labeled Bullseye glass as “90 COE”. At the beginning, we labeled the sheets – and still refer to them today as – TESTED COMPATIBLE. Due to the confusion that arose when other companies entered the market and adopted the term we’d coined, we now label our sheets BULLSEYE COMPATIBLE. My two earlier blogs in this series define exactly what this term means.
read more

Sorry to be dragging my feet on this subject. I have to confess to finding it a little tedious. For me, technical information is like lifeboat maintenance on the Titanic. No one really cares about it (myself included) until something goes wrong.

Then you’d like to know that the equipment doesn’t have holes in it.

Last week I went over basic compatibility testing as it was established at Bullseye and has been practiced in our field, with little or no variation, for the last 25 years. Whether that test is being performed within the factory or the artist’s studio, it is not – and never has been – a measurement of the so-called COE. What is measured is the strain that exists at the interface between the chip and the base glass.

WHAT STRESS?! By Bullseye’s factory standards the four chips on the far right of this bar are considered incompatible. Chips 1570 and 1572 are low relative to the base clear. Chips 1573 and 1580 are high relative to the base. Compare this bar with one in which many of the samples are very obviously out-of-compatible range
read more

Third, and last, on my list of “Unbeautiful Things” is the manner in which kilnforming is being marketed today. I have some pretty strong opinions on this, so if you’re not ready for another rant, you may not want to keep reading.

This is what STRESS looks like. It happens when glasses that are not “compatible” are fused together. Understanding it is the foundation of glassforming.

IMO reducing a rich and fascinating field to a litany of assurances that success will come from buying a glass with a “wider margin of error” and a kiln that a dog can program does a disservice to the many exceptional artists who have worked to advance the reputation of the medium and to the beginners who deserve to be educated, not harvested.
read more