Ever blown glass? I sure hadn’t. Holy balls it’s fun.

My partner Danielle gifted me a birthday present: nzglassworks.com/products/beginners-glass-blowing-workshop-level-1-2025 It’s a day-long workshop on beginner glass-blowing, at the New Zealand glass works in Whanganui.

She and I had previously visited in January 2024. It is a very wacky place. Its lower level contains the actual glass-blowing workshop, with industrial apparats and safety gear and volcanic glowy shit, you know, the serious crowd-pleasers. The upper level surrounds it in a kind of broad balcony affair. Within the balcony lurks a delightful gift shop, containing usual glasy fare: earrings and paperweights and other bits and bobs. Priced sanely.

A few examples (click to embiggen):

Neighbouring this is an art gallery. It contains spangly artworks. And glittery artworks. And bodacious artworks. Priced accordingly. Holy crap. I think the most expensive was $18,000. No lie, the technical sophistry of these glass-based artworks genuinely dazzled me, but golly gosh that’s a wodge of dough. Though I must admit, my reaction was split roughly 50/50 between “what kind of pampered dummkopf would ever pay that” and “omg sign me up bro”. Check these out:

Whanganui’s glass works was one local attraction among many. Danielle and I passed through, and I snapped snaps of some of the most eye-watering artwork price tags, and we had a good laugh, and I’d not thought much more of it.

Then my birthday rolled around. And she bought me an introductory glass-blowing workshop lesson. How fab is that?

Craftsmanship of any flavour always fascinates me, and I try to learn its ways whenever I can. Most of us are aware that glass-blowing is a Thing. Our grand galaxies of modern glassware presumably don’t just pop into existence like magic. In some form or another, glass products have existed since the dawn of friggin’ civilisation, haven’t they? Glass-blowing in particular must have its own unique set of crafting techniques. Right? I can’t imagine you’d pour glass into moulds like metallurgy. You’d never get ultra-smooth wine glass surfaces. The modern world contains millions of industrial items, via billions of distinct manufacturing techniques, and as gnarly as it’d be to learn at the least the basics of the lot, I’d kind of just missed the boat on glass. Do you squidge it like Blu-Tack? Or chemically torture it? Could glass-”blowing” involve blowing soap bubbles? Or blowing on it like hot soup to cool it? Who knows?

So along I popped, full of questions and inquisitiveness.

Turns out glass-blowing involves insane quantities of heat, and even more insane quantities of grasping and spinning metal rods. I arrived bright and early at the Whanganui glass works, then met my teacher and fellow classmates.

The workshop-proper contains a multitude of benches and workspaces, with three bits of apparatus along the back wall.

The centre, and largest, is a ginormous ceramic cauldron-hutch-beastie with an incredibly heavy and incredibly closed door. It’s flanked either side by twin igloo-things, lighter but still hefty, each sporting a circular hole, within which lurks a generous internal cavity. Brilliant yellow light blasts forth, accompanied by stupendous quantities of heat.

Like, seriously volcanic. LED control panels on the wall behind insist these interiors are being maintained at exactly 1237C. Google assures me that the blackbody radiation produced by an object that hot indeed makes yellow light. Cripes. These igloo-things don’t house a single lightbulb. They’re literally yellow-hot.

Our teacher proudly introduced these twin contraptions to us newbie padawans as Glory Holes. At the time I thought she was just being racy, an impression only reinforced by copious amounts of grinning and cackling, but whilst writing this I researched further, and no, turns out (1) that’s their official name, example at kilns.co.uk/kilns/glass-blowing-glory-hole, and (2) it would appear this glassblowing parlance actually predates the more modern naughty-usage. Obligatory thread discussing this: reddit.com/r/todayilearned/comments/4mfoet/til_the_term_glory_hole_originated_in_glass/ My my. Glory hole it is.

She then asked who among us might first like to make a giant glass droplet. Me, that’s who. She grabbed a metre-long steel rod from a rack housing around ten more, each with a blowtorch flame licking one end. She placed the non-volcanic end in my hands, then beckoned me over to the cauldron-hutch-beastie and opened its door.

Good lord. I’d never experienced heat like it. The physical wump of heat enamating from within the cauldron-slab felt like being turkey-slapped by Smaug. Within lurked a shimmery pool of radiant gunk, blazing yellow-hot. Glass, it would seem. Under our teacher’s guidance, I poked my rod within, enticed a lovely radiant blob aboard … and she requested me to start rotating the rod around in my hands, in what promised to be the day’s first rotation of around 27 million.

For molten glass is incredibly goopy. It’ll drip from a stationary rod in seconds. You coax it aboard by keeping one’s metal bar under constant, constant rotation. You hammer and sculpt your blob whilst maintaining this rotation forever..

Unless you’re building something incredibly simple like a drip-shape. The teacher encouraged me to hold my rod overhead and oscillate it back and forth like a pendulum, stretching the blob from the tip. It was rapidly cooling, losing its yellow lustre, then dimming red. Classic black-body radiation. As it cooled, it hardened, and ceased all gooping. The teacher bounded forward clasping a blowtorch, and gave the frozen blob a thorough seeing-to.

It regained its yellow radiance and resumed glooping, cooled, froze, blowtorched, glooped anew, and my classmates and I beheld a lightning-fast education in the dazzling interplay between glass’s temperature and viscosity. When kept near melting, it glows and it gloops. Remove one's heat source and it freezes fast.

At length she’d teased my rod’s blob into a drip-shape a foot long. She directed me to another work bench, grabbed a knife immersed in room-temperature water, applied the blade to her desired blob-break-point, and the blob immediately and cleanly snapped off the metal rod. Thermal contraction in action. Finally, the blob went into a slightly-volcanic cupboard called an annealing kiln, which she assured us would then be cooled overnight, incredibly slowly, thus safely bringing my drip and the day's other creations down to room temperature.

The other three students jumped through the same process, one by one. Three more great drops into the annealing kiln.

Doohickey Two: paperweights.

This time, we’re encouraged to follow similar actions, but refrain from pendulumming, and instead keep our molten rod-blob vaguely spherical. This will form our paperweight. Then we’re directed to a work bench, with a chair and two horizontal rails, on which you continue rolling and rotating your rod with your left hand, and with your WIP glass on your right side, and with your right hand apply to it the tools of your choice.

Specifically, huge metal tweezers. A simple, unadorned glass sphere can be a hideous fire risk, even when not volcanic. Strong sunlight against curved glass produces a magnifying effect, which can ignite things and burn your house down. I hear homeowners frown on this. Our teacher encouraged us to physically attack our yellow/red-hot blobs with a great honkin’ set of metal tweezers, and sculpt ridges and hollows and holes in our rod-blob, then coat the blob in another layer of cauldron-glass, called a “gather” in glass-blowing parlance.

I got stuck in. This was the first tactile experience I’d had so far with molten glass itself. Turns out yellow-hot glass is somewhat goopy, like chrome-snazzy Blu-Tack. Merely red-hot glass, however, becomes spectacularly viscous, like the thickest tar you can imagine, and you have to shunt serious force into deforming it.

And it cools bloody fast. You have a roughly twenty-second window to work your steel-tweezer magic, then it’s back to the Glory Hole for reheating.

Then back and forth and back and forth until you’re satisfied.

I twisted and twiddled my red-yellow-blob at tedious length to form ridges and hollows, then submerged the ridges and hollows in additional molten glass gathers to produce internal voids, and then used a handy wooden sculpting-tool with a hemispherical cup to persuade my glass-goop to remain vaguely spherical.

The cup-tool reminded me of my grandmother’s wooden chopping boards, in that it looked like it’d been used around twenty thousand times over as many decades, in a similar fashion to an ancient and beloved teapot, or a cast-iron frying pan. Aeons of character.

Then one narrows the paperweight's neck with a second set of rather sturdier tweezers.

Finally, it's off to the cold-knife work bench and snap the glass-goop paperweight free of the steel rod.

And fling it into the annealing kiln alongside the glass drop.

Item Three was a second paperweight, this with enough internal colour and opacity that it attenuates sunlight and internal safety cavities to disrupt rogue lensing prove unnecessary. Yes. Colours. So many colours. One method of introducing colours is brightly-coloured sand or gravel, which you press your blob against.

The mechanics and crafting of our technicolour paperweights were otherwise similar to the previous lot, so I won't repeat them here.

Item Four is a cup. A whiskey tumbler. And for the first time in our glass-blowing sojourn, us newbies encountered actual literal blowing.

Turns out it’s how you produce hollow glassware. Of the steel rods upon which you gather your molten-goopy glass, some are solid, and others are hollow. You literally blow down one end, and the hot glassy-end inflates into a literal bubble. It’s neat. Or rather, you form two-person teams, with one person controlling the unrelenting rod-rotation and the cup-tool sculpting, and the other in charge of applying air pressure. This forms a bubble.

Coaxing such a bubble into an actual whiskey tumbler shape requires extra steps. The side of the blob furthest from the metal rod forms the tumbler’s base. You flatten it.

Also, note that wooden board. It's being held by another classmate, between the current classmate's proto-tumbler and her gloved hand, physically blocking line-of-sight. Why? Good gosh it's friggin' hot, that's why. That glass is undyed. It's still yellow-hot, still over a thousand degrees. You can feel the heat blasting off one's goop-glass, even through thick safety gloves. You sweat buckets. The glass works sports a water cooler. I've never seen a water cooler with such heavy wear and tear. I remain amazed the glass works' management didn't go the whole hog, so to speak, and just construct a water cooler in the shape of an enormous lactating sow, and just have every workshop inhabitant permanently suckle from it. It'd save a ton of hassle.

Anyway. With the aid of your sturdy metal tweezers, you narrow the neck of your blob.

You adhere a second metal rod to your tumbler's base via a dab of molten glass, then you snap the narrowed neck and remove the first rod, and now you re-widen the narrow neck with those great honkin' metal tweezers from before into a shape actually resembling a tumbler.

Then detach Rod Two with further cold-knife-stabs, and mission accomplished!

The next morning, I popped back to collect my own winnings:

Glass-blowing has proved to be one of the most fun experiences I'd had in months, and I'd recommend it to anyone. Getting seriously expert in any craft takes years, and I suspect there's a slight gulf between fashioning these simple neon blobs, versus sculpting intricate laboratory apparatus or, possibly, a work of spangly art north of ten grand.