Steam Launch Estral

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STEAM LAUNCH – ESTRAL
Marine engineer (retired) Bill Voisey sent in the above photo of his 21’ kauri steam launch – Estral. Estral has a a beam of 8’6” and draws 3’, and was originally built in Port Chalmers, for a Riverton Rocks farmer c.1940s. Bill understands this family (Jaimison) owned and used her until the 1990s.
Bill restored Estral and converted her to steam in the 1990 > 2000 period with the installation of a Stewart Turner 6A steam engine, and a Stirling  water tube boiler.
Video below of engine prior to clean up and painting
Video below showing back of engine showing boiler feed pump, and condensate pump.

The vessel is currently being re painted and tidied up to put it back in the water. Below is a summary of her set up:

Engine. Stewert Turner No 6a, 2 cyl compound,
Pumps engine driven condenser pump and boiler feed pump.
Keel condenser with return to hot well.
Prop 16″x 18 pitch. Hull speed 6 knots .
Stern tube oil filled with mechanical seals?
Thrust block fitted with forward and reverse thrust bearings.
12 volt alternator v belt driven from prop shaft.
Water tube boiler,pressure tested to 600lbs static pressure,stamped by inspector at 400lbs (not marine certified.)
oil fired automatic pressure controlled with Beckett oil burner fitted.
Water level kept by manual control via needle valve bypass.
Engine can be run to atmosphere
Tanning type boiler water treatment used.
Boiler always left with the total boiler system full of treated water filled from hot we’ll by hand boiler feed pump.

30-01-2020 Update – Russell Ward requested more details on the boiler. The below was supplied by Ben Voisey

“The Boiler design is of the type of water tube boilers common in the late 1890’s, taken from an article in book No 5 of the Modeltec magazines Sept 1988 page 27.
I adapted the design to suit the available space in the hull of Estral.
As you can see the design can be varied as to width, height and length with ease.
The headers at each end have only a 1.5 “ gap and the total of the boiler’s water capacity is under 30 litres .
Fuel type can be whatever suits the furnace that is designed, in this case oil fired.
These photos were taken when I did the last boiler clean.”

 
Hopefully I’ll See Some Of You Tomorrow At The Mahurangi Regatta – If You Don’t Make It, We Will Have Coverage In Tuesdays WW Story 🙂

 
WAITANGI DAY WOODY BEACH PICNIC – FEB 6 – Put A Circle In Your Diary, All Woodys Welcome. RSVP Below
Woody Waitangi Picnic

2 thoughts on “Steam Launch Estral

  1. Mmm looks cute. The engine is a Stuart Turner 6A (not Stewart). I’d love to know more details and see a pic or two of the boiler -a Stirling type. Maybe Bill will advise.

    Like

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