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FEATURE

HackSpace Learns... Glass-blowing

HackSpace makes a Christmas bauble – we’re going to need a bigger tree...

GLASS-

BLOWING

HackSpace learns...

umans have been creating with

glass since ancient times. Not for

as long as we’ve been using wood,

stone, or metal, but they’re naturally

occurring, and our ancestors could get

them from the world around them.

Unlike those materials, glass needs to made before

we can make anything out of glass.

It needs high temperatures, the right materials,

a load of skill, and a combination of things to go

right if you’re not to end up with a load of, well,

broken glass.

We were lucky enough to have a go at

glass-blowing, thanks to Hen Ogledd Glass

(henogleddglass.co.uk), a team based in Cumbria

who are keeping this ancient craft alive, taking it to

the people, and creating some unique handmade

pieces along the way. Josh and Ann started their

own studio only recently, after training at the

University for the Creative Arts, and working with

master craftspeople in Somerset and Devon.

WE ARE GLASS

We start with the raw materials. In this case,

that’s premade glass pellets, as Hen Ogledd’s

Ann explains: “We buy in our raw, plain glass in

pelletised form. When the glass is made from its raw

chemical constituents, it takes around three days of

H

heating at 1600°C. Then you’ve got to let that sit so

all the bubbles rise out, to ensure it’s in the same

condition throughout. We have a mobile furnace, so

if we did it that way we’d have to be here three days

in advance, burning gas 24/7.” This speeds up the

work, but glass is such a good insulator of heat that,

even at 1200°C, it takes three hours to get the glass

up to temperature.

After the furnace, the tool you’d most obviously

associate with glass-blowing is a metal tube, called

the iron. The first step is to dip the iron into the

molten glass that’s sitting at the bottom of the

furnace. This comes out glowing reddish-orange,

and you have to keep twisting the iron in your hands

to stop the molten glass dripping onto the floor, like

honey on a spoon. We take a deep breath and try to

squeeze some air down the tube and into the glass.

Then we try again, but this time harder; the glass is

molten, but it’s still viscous and heavy, and the first

breath in takes a lot of effort to break the surface

tension and introduce a bubble into the glass.

Now it’s time to add the colours. These come

as granules of broken glass, into which we dip

the molten glass in the same way you’d put

breadcrumbs on a bit of meat to make schnitzel,

first on one side to add the yellow granules, then on

the other to add the green. This isn’t as simple as it

looks, however...

By Andrew Gregory @andrewgregory83