Making copper spiral tube
How to make a copper coil for a HERMS system and wort chilling from 12×1 mm Cu pipe – including the trick for removing packed salt.
- 2 min read
Making copper spiral tube
For my DIY microbrewery I needed two copper coils:
- HERMS coil – for heating the mash by circulating it through hot water
- Wort chiller coil – for rapidly cooling the wort after boiling
Copper was the obvious choice: it has roughly 20× better thermal conductivity than stainless steel, significantly reducing heat exchange time. Durability was less of a concern since I won’t be brewing 24/7; cleaning in citric acid handles any oxidation.
Parameters
- Cu pipe: 12×1 mm half-hard, 5 m
- Price: 515 CZK (~21 USD)
- Source: triker.cz – Cu pipe 12×1 mm half-hard
Procedure
- Fill the pipe with salt – this prevents kinking during bending
- Wind the pipe around a drain pipe used as a mandrel (my wife helped by walking around it :D)
- Shape into the desired coil diameter
Getting the salt out
This turned out to be the hardest step. After bending, the salt was compacted and nothing worked – pressurised water, knocking, even vinegar. The solution:
- Connect a garden hose to one end and pressurise
- Close the valve and leave for 1–2 hours
- Open the valve – the built-up pressure forces the salt out
It took 2 hours but it worked. It turns out others have had the same problem:
How to get the bloody salt out – Tapatalk (the author there used compressed air instead).
- Tags:
- Homebrewing