Glassblowing FAQs
What is glassblowing?
Glassblowing is the art of shaping molten glass by inflating it with a blowpipe. The process starts with glass heated in a furnace until it’s the consistency of honey. Artists gather some onto a blowpipe, introduce air through the hollow tube, and shape it using specialized tools, gravity, and controlled reheating. This allows for the creation of everything from drinking glasses to large sculptural works.
How hot does glass need to be?
Glass must reach extremely high temperatures before it can be worked. Temperatures of over 1300°C are needed to melt raw materials into molten glass. While shaping, artists can work glass between 1150°C and 1250°C. At this temperature, glass is soft enough to move but still stable enough to control. As it cools while being shaped it hardens and becomes unworkable, which is why frequent reheating is necessary during the process.
Do I really have to blow into the pipe, and what will I actually do in a class?
Yes — part of the fun of glassblowing is adding your own breath to shape the molten glass. In a beginner class, you’ll get to blow into a long steel pipe while the instructor gathers the hot glass and sets it up for you. Don’t worry — it doesn’t take much effort; a gentle, steady breath is usually all that’s needed. Your role will depend on the project: you may help inflate the glass, roll the pipe on the workbench (called a marver), or use tools to add texture or shape. The instructor will be guiding you making sure you stay safe while still experiencing the essential actions of glassblowing. By the end, you’ll have a piece you truly been part of making.
What tools do you need for glassblowing?
A glassblower’s toolkit includes both large studio equipment and handheld tools: Furnace – keeps raw glass molten. Glory hole – a high-temperature chamber for reheating pieces mid-process. Blowpipe – a long hollow steel tube for gathering glass and introducing air. Punty rod – a solid rod used to transfer or finish pieces. Marver – a flat steel or stone surface for rolling and shaping. Jacks – tweezer-like tongs for forming necks and openings. Shears, paddles, tweezers – for cutting, flattening, or pulling shapes. Annealer – a kiln that slowly cools the finished piece to prevent cracks.
What is annealing and why is it needed?
Annealing is the controlled cooling of glass inside a special oven called an annealer or lehr. If hot glass is left to cool too quickly the glass is stressed that leads to cracking or even shattering. Annealing prevents this by lowering the temperature gradually over several hours (or days for very large pieces), ensuring the glass is stable and durable.
Why is molten glass orange/red?
When glass is heated to working temperatures, it glows bright orange or red because of its extreme heat—not because of its actual colour. Even clear glass looks fiery when molten. Coloured glass also appears different while hot; for example, blue glass may look hot pink or purple when glowing. The true colour is only visible once the piece has cooled completely in the annealer.
How is colour added to glass?
Glassmakers add very densely coloured glass to the clear glass to create coloured pieces. Because each glass formula expands and contracts differently with heat, artists must choose compatible colours to avoid stress and cracking. Glassblowers use several methods to add colour: Colour rods or canes – solid coloured glass melted into clear glass. Frit – crushed coloured glass in sizes from powder to small chunks. Layering – combining multiple colours through gathering and casing.
Can beginners or children try glassblowing?
Absolutely. Many studios offer workshops where first-time students can create simple pieces like paperweights or ornaments in a single session. Children are often welcome, usually starting around age 12 depending on the studio’s policy. Projects for beginners are carefully supervised while still letting students experience shaping and blowing glass safely.
How long do glass pieces take to cool?
The cooling process depends on the size and thickness of the piece. Small ornaments or beads may be ready in a few hours, while pieces or sculptures may require 24 hours or more. Glass cools inside an annealer, which lowers the temperature in controlled steps. Students should expect to pick up their work later or have it shipped once it’s fully cooled and safe to handle.
Why is blown glass expensive?
Blown glass pieces are priced higher than mass-produced glass because of the materials, equipment, and labour involved. Furnaces must run at high temperatures consuming a lot of energy. The raw materials are costly, and the process is time-intensive—every item is made by hand, often requiring multiple people to assist. Each finished piece is unique, and the cost reflects both the skill of the artist and the resources needed to produce it.
What about scientific glassblowing?
Scientific glassblowing is a specialized branch where glassworkers create lab equipment, medical devices, and precision instruments. Unlike artistic glassblowing, this is usually done with borosilicate glass (like Pyrex) using a torch instead of a furnace. It requires exact measurements, technical drawings, and often years of training. Scientific glassblowers combine craftsmanship with engineering to create functional, heat-resistant, and pressure-safe apparatus. Artists also use these methods to make one off artistic pieces using borosilicate glass heated with a torch.
Is glassblowing eco-friendly?
Glass itself is highly sustainable because it’s 100% recyclable and can be melted down and reused indefinitely without losing quality. Many studios recycle scrap glass (called cullet) back into new batches. However, glassblowing does require a lot of energy to keep furnaces running continuously. To offset this environmental impact, eco-conscious studios prioritise energy efficiency and material reuse in their operations.
Find out more
During a private 1:1 lesson you make a solid piece (eg candle holder) and 3 blown pieces e.g. drinking glass/ vase/bowl). During a 1:2 experience you both start with a solid piece (eg.candleholder) then progress onto a blown piece each. In a 1:3 session you all make a blown and a solid piece each. Please contact me for larger groups and we can discuss what would suit. In all sessions you can choose from a wide range of colours to make glass which will be yours to keep.
The studio is 5 minutes walk from East Finchley Underground Station, zone 3 on the Northern Line. There is parking if coming by car.
Please note your work will need to be annealed overnight in a kiln to eliminate stress and can be collected or posted to you at the earliest opportunity after the session.
The experience requires moderate manual dexterity and access to the studio is via 12 outside steps.
