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[ooyah/2]

CORPOSANT AS REQUESTED.

Hi Mike
 Here are some pics of my CERVIA, she is 40 years old and started out as being electric powered and was built from a free Vic Smeed drawing .
However after building the frames at 1/4" scale it was too small so I redrew it to 3/8" which made it 42' long and at that time steam power was far from my mind.
It lay up in my loft for 25 years before I remembered that it was there and by this time I needed something to take my mind off work so I bought a lathe and started to convert her to steam.
The engine was machined from Stuart 10V castings and the boiler was designed and made by myself (similar to the black one in the pics ) all the valves and bits and pieces were scratch built ( I like making boilers).
As you know Single cylinder engines are not self starting so with a slip eccentric and Meccano gears it can be done.
As I need a new challenge I am going to machine up a set of D10 castings and make it with reversing gear like the engine I have shown with my Puffer which I will install in the boat over the winter, although the 10V can be started and reversed it is not 100%, at present it runs at 50 psi but that will be too much for a D10 in such a small boat so probably will run at 30 psi. .
The all up weight at present is 34 lbs and the boiler is fed by a pump using pond water.

I am off now on holiday to the lake district so it will get my mind of steam boats and the fast electric K7 that I am building, will probably stop in at Conniston to the D Campbell museum.
George.

[kno3]

Lovely tug! What heated surface does you return flue boiler have?

[ooyah/2]

Kno3,
The boiler was made by myself and is similar in design to the boiler shown with the exception that it has 20 return tubes,
Neglecting the back and front plates there is approx  118 sq" of heating surface.
Boiler is fired by a plumbers blow lamp head and the gas is a camping gas can which I refill with Butane from a 4.5kg bottle. once steam is raised I can sail for as long as there is gas in the tank and water in the pond which can be 3 hrs.
Before all you guys start  pointing out that you shouldn't refill these cans, I am well aware of that but with experience gained over the years  it can be safely done.

George.

[south steyne]

Hi do you have any pics on how the feed pump works and how it is controlled
Cheers
John

[Corposant]

George

Please accept my humble apologies - I missed your July post responding to my request for pictures of your Cervia. (July was not a good month as I nearly lost Mrs Corposant during emergency surgery for a twisted gut - but she's made a good recovery and her "plumbing" will be put back to normal in the new year.)

So, a belated thankyou for the pictures and explanation. Like your Puffer, she is superb and a brilliant example of model engineering. The saga of her development gives me great encouragement over the slow progress I'm making with my Puffer (electric powered!).

Mike

[ooyah/2]

Hi John
The pump in the Cervia is tucked underneath the bow and is powered by a 12 v battery through a small reduction gearbox with a disc on the shaft and a Scotch crank to move the 1/4" dia pump ram, I find that 120 strokes/min is about correct but  I can alter the stroke via holes in the disc,also if the valve starts to blow off I can switch the pump off by a servo for a little while ,experience lets you know how the boiler is getting on.
The gearboxes that I use are no longer available but if you go to MFA-COMO gears   http://www.mfacomodrills.com/ you will see a selection of gearboxes in their
918D &919D ) range with all the various speeds. great little gearboxes and not too expensive. The only problem is that you have to make a support to prevent the gears moving, see the pic No 2 not a big job.
I hope this helps you


Pic No 2 you can see the support just to the right of the red end cap


Hi Peter,
No apologies are necessary, your good lady must come first and I am glad to hear that she is getting better,  Keep at your Puffer and if I can be of any help let me know 
George.