Introduction

Boilers using this technology come in a variety of shapes and sizes.  However, the potential user would be advised to think carefully about the use to which s/he wishes to put the technology.  In the contex of this site we are most likely to be concerned with steam plant to power launches of up to about 20ft/6.1m.  This is firmly in the hobby boating arena but given that a typical engine might be a Stuart Turner Cygnet, it would be fair to say that any applicationto which that sized steam engine might be put could be powered by a mono-tube steam generator.

To begin the 'story' we offer you the development of the boiler in Snipe by John Emmett.  In some ways this is beginning at the end in that this is a very recent design.  However, we also consider some of the earlier designs that have featured in the pages of the SBA's magazine Funnel over the last 50 years on the 'Featured in Funnel' page.  We should remember that the monotube boiler is not a new idea by any means and the basics of the technology were well worked out before 1900 as is explained in this edited article about the Herreshoff steam generator.  The difference today is that we have rather better pipes, insulating materials and monitoring equipment than were available then. For those who prefer videos to text, the story of the Lynx mono-tube boiler development can be found on the Links page.

Happily there are many modern builders who are happy to share their stories and designs.  A first contribution in that area is from John Draper, a member of SBA Australia. However, in terms of time order we should really be considering Sven Olof Carlberg's outboard motor which was developed from the 1950s.

The Designs

1.  Snipe - Horizontal coil
2.  The various boilers featured in Funnel Magazine (On going)

  • Funnel - Issue 15 p. 73. March 1978 George Wall - Coil Boilers.
  • Funnel - Issue 45 p. 35. Autumn 1985 G B Young – A monotube boiler.
  • Funnel - Issue 48 p. 40. Summer 1986 Wally Mounster – Development of a modern steamboat – Part 1 – A monotube boiler.
  • Funnel - Issue 49 p. 33. Autumn 1986 Wally Mounster – Development of a modern steamboat – Part 2 – Boiler control.

  • Funnel - Issue 92 Spring 1997 Jim White - The development of a Small Monotube Steam Generator

3.  The Herreshoff steam generator
4.  John Draper's Triple Coil Boiler
5.  Sven Olof Carlberg's outboard motor with monotube boiler
6.  Designing a boiler for the Fairlight Canoe (a sort of Blog)

7. Mike Tilby's Electronically Controlled Mono-Tube Boiler

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