Free blowing shapes hot glass with breath, gravity, constant rotation and hand tools alone, with no mould. The sequence is to gather glass on a preheated pipe, roll it on the marver, blow a small bubble, then shape by blowing, swinging and tooling, reheating in the glory hole whenever it stiffens. The pipe must never stop turning, because hot glass sags within seconds, and the finished piece must go straight into the annealing oven.
Part of Glass Blowing and Forming
Shaping hollow glass without a mould, using breath, gravity, rotation and hand tools.
Free Blowing Is A Sequence Of Short Operations On A Cooling Gather
The glass starts at working temperature and loses it while you shape it. The corpus’s Glassblowing article calls free blowing the foundational skill, and states that the blower shapes entirely by gravity, centrifugal force and hand tools. The operations below each have their own article.
| Operation | What happens | Article |
|---|---|---|
| Gather | Pick up molten glass on the pipe tip | Gathering |
| Marver | Roll to centre and cool the skin | Shaping and Finishing |
| Bubble | Inflate the first parison | Bubble Formation |
| Shape and finish | Jack, swing, open, trim | Shaping and Finishing |
What You Need
- A furnace with a crucible of glass at working temperature; see Glass Properties for Blowing.
- Blowpipe, pontil and a toolset; see Tools and Equipment.
- A glory hole, and an annealing oven already at its hold temperature.
Method: A First Piece
Step 1: Preheat the pipe tip in the glory hole until it is hot; cold iron cracks the glass.
Step 2: Gather. Dip, rotate slowly and withdraw while turning.
Step 3: Marver. Roll the gather into a cylinder on the marver.
Step 4: Blow a short puff to start the parison. You should feel a moment of resistance, then give.
Step 5: Shape and reheat. Blow gently, swing the pipe, reheat as needed.
Step 6: Finish the lip after transfer to the pontil and crack off.
Step 7: Anneal immediately. The carrier states unannealed glass will crack within hours.
Common Mistakes
- Blowing hard. The glassblowing article calls for gentle, sustained pressure for even walls.
- Stopping the rotation. The carrier explains that hot glass sags under gravity; a pipe that stops turning gives a lopsided piece within seconds.
- Uneven walls. Thin spots blow out and thick spots do not stretch.
- Skipping the oven for “just a small piece”. Every piece must be annealed, no matter how small.
Safety
Hot glass does not look hot
The finished piece, the pontil scar and the end of the pipe look cold once they fall below about 600 °C, but they burn. Put finished work only on a marked tray or straight into the oven.
Never inhale through the pipe
Only breathe out into it. Drawing breath through the pipe pulls furnace air into the lungs.
What’s Next
- Learn next: Gathering — the first operation in detail
- Combine with: Mold Blowing — repeatable shapes from the same skills