The art of scientific glass blowing (2018)

> Was this a purely hands on course? How was it graded?

Almost purely hands-on. It has to be. I dabble in guitar, and like a musical instrument, no amount of reading theory will train your hands to have the dexterity and muscle memory to manipulate soft glass.

We had about 8 projects over the semester. The instructor demoed how to make the project and things to look out for, usually stress in the glass or why you want to build something a specific way.

We had a thin handbook that wasn't really used, and might have actually been published by a company like Corning. I think it covered some of the properties of glass.

We got to warnings at the beginning of the semester: if you care about your GPA, take it pass/fail--there were no A's the prior semester, and you'll get a B if you put in an honest effort, you need to do good work to get an A. The second warning was someone goes to the student health center every semester, and everyone will get a minor cut or burn.

You didn't ask, but a some surprises with glass:

- It's surprisingly strong in the right circumstances. Drop a glass marble on a hard surface and there's a good chance it doesn't break.

- Borosilicate is amazing; it should be the only glass in your kitchen. Its tolerance to rapid temperature chances only works in one direction--cold-hot-cold can make it shatter.

- You can "unbreak" glass. I had a project that started to get a stress fracture as it cooled. I quickly put it back in a cool part of the torch flame to anneal it. The cracks literally healed.

- Different glasses have different thermal expansion properties, so when you join them, you might need an intermediate glass.

- We built everything from tubes. The way you "cut" a tube is score it a few mm with a tungsten carbide scoring knife, firmly grab in both (bare) hands, and snap it away and out. Snap it wrong and the tube shatters in your hands.

- Glass conducts heat poorly. You usually hold the project with a bare hand while the other end is in the flame.

- Early on, I remember being somewhat afraid of using a big flame, and struggling with part of the project. The instructor just told me to use a bigger flame. Use the right tool for the job.

The rest of the knowledge seems to be passed person-to-person, mostly in informal settings. There's a decent program at Salem community college, but it's just too short to become a fully-capable scientific glassblower. That takes about 10 years of full time apprenticeship, which is why the field is dying out.

I've (briefly) studied with some extremely talented glassblowers (Sally Prasch, ...), and I found that helpful, but also most of the learning came from staying up to 1AM trying to replicate something that took them 5 minutes to demonstrate...