Paddleducks

Other Marine Models => Live steam => Topic started by: malcolmbeak on March 30, 2012, 09:13:53 PM

Title: 3 cylinder paddle engine
Post by: malcolmbeak on March 30, 2012, 09:13:53 PM

3 cylinder paddle engine



http://www.paddleducks.co.uk/smf/index.php?action=downloads;sa=view;down=372

Title: Re: 3 cylinder paddle engine
Post by: peter ravenscroft on April 03, 2012, 12:07:45 AM

i have just downloaded the plans that have just been put in the download section and i am intrigued
 what size of boat would it propell and what type of boiler would it need
regards
peter

Title: Re: 3 cylinder paddle engine
Post by: malcolmbeak on April 03, 2012, 03:09:28 AM

Peter
Good question! A lot depends on what pressure it is run at and how well it's made. The answer is that I don't really know, but I would expect running at about 30psi with paddles 4 to 5" diameter with floats about 1.5" wide would present no problems.
Any type of boiler should be OK - Centre flue: return flue or some sort of vertical would all work well enough obviously provided thy produce enough steam. In order to know how much steam is needed, we need to know the scale speed , the paddle diameter and how fast the engine must run to give that speed. Reckon on about 1/3 slip. Knowing the swept volume of the engine, the volume of steam required can easily be worked out.
I always design my own boilers to suit the particular model. I would suggest "Model Boilers and Boilermaking by K.N.Harris as an excellent book for getting into boiler design.
Is this any use to you?

Malcolm

Title: Re: 3 cylinder paddle engine
Post by: peter ravenscroft on April 04, 2012, 12:57:59 AM

thanks Malcolm
                       i have kn Harris 's book I'll look it up for a boiler you just might have tempted me into start building one then find a boat to put it in
regards
peter