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[785boats]

Hi guys.

A little help if you could.
I recently bought, among others, a set of plans for the Josie Olsen from 'Vintage Model plans'.
It is a side paddle river boat with a Walking Beam engine.


https://www.vintagemodelplans.com/products/side-paddle-river-boat-josie-olsen-311-2-full-size-printed-plans-for-radio-control?_pos=6&_sid=e5d544775&_ss=r
[/size]
Now , sad to say I know, but I do not have the skills or abilities to venture into the world of steam.
The original plans are for an electric drive and that is what I am going to do.

The question that I need to ask, is what sort of revs are we looking at here for this type of engine.

I don't want the beam to be rocking so fast that it looks rediculous.

I take it that one up and down movement of the beam equals one revolution of the wheels. Or was there some sort of gearing involved in the real world?

Any help with the revs in the model world, would be greatly appreciated.

All the best.
Paul.

[GG]

785boats,
            Ah, something I puzzled about when building my first RC paddle boat.  Couldn't find anything useful to at least get me in "the right ballpark" as far as the relationships between wheel size, rotation speed and desired model speeds.  So, I used the idea of taking the rim speed of the paddle wheel (circumference times rotational speed) and estimating the "slip" to be around 50%.  This worked reasonably for my simple wheels of around 4 inches (100 mm) in diameter and models of modest performance.


Did some more work on this topic including thrust, blade immersion and rotational speeds.  Well, I needed something to occupy me during "lock-down".  As this has formed the basis of an article submitted to but yet to be published by the Editor of the Model Boats magazine, I can't with any decency detail it on this forum and still expect the Editor to publish it.


I'll just say that faster the wheel turns, the more thrust it generates but only up to a point.
Glynn Guest

[tghsmith]

visit the "paddleducks" web site..  from what others have built this type of boat requires attention to weight of cabin and upper works....

[785boats]

Hi Glynn.
Thanks for the response. Some good points there.
You may remember years ago I built up an enlarged version of your Phantom Blockade Runner.
She still runs beautifully when I take her out. I should take her to the club more often.
I've been playing with a mockup of a rocker, & figure that at a paddle speed of 60rpm the beam will go through one up & down cycle each second.
It looks to be a nice speed as long as that paddle speed pushes the boat at a decent speed. the wheels on this one are 120mm in diameter.


tghsmith.
Thanks for the tips. I'll go and look over on Paddleducks.
I also think that a crosswind will have a big effect on all that 'sail area' above the decks too.
But it will be built as light as possible.


Cheers.
Paul.