Ratio between hull cross section and swept area

[freedem]

In studying paddlewheelers I have failed to find any relationship
between the area of the cross section of a hull comapired to the
area of the floats
Thankyou to any one who would please offer their thoughts on
this ratio.
does the intended service area or speed of the vessel effect the
prefered ratio?
best wishes to all
jeffery

[Mike Mayhew]

Having been associated with paddlers both real and models for over fifty
years I agree with you there is no relationship at all. Designers of such
craft were influenced by dock sizes, stability of basic hull form, and so
on. The only relationship at all was the fact that the floats just submerge
when on their lowest point of travel. P&A Campbells , on some of their
steamers tried metal floats in place of the wood originals, and some of
these were curved. It was reasoned that they would be less likely to
damage from driftwood etc and give more speed...Answer to both was a slight
Yes. The overall width of the steamer was governed by the Lock sizes in
Bristol Docks. Some Austrian steamers, Gisela, for example have very
narrow floats. The Director tugs we had in the dockyard at Plymouth in the
50's had very wide floats . So.. I believe that it was left to the designer
, how he felt and the working location of the boats .Best Regards ..... Mike
Mayhew

[Paulrjordan]

Hi Jeffery:

This is a very interesting topic and particularly relevant to a
research project I have which is the 180' Clyde built Excursion
Paddle steamer "Worthing Belle" (originally built as "Diana Vernon"
in 1885 by Barclay Curle for The North British). In spite of
exhaustive research in Scotland earlier this year there seem to be no
known plans for her. Specs that elude me completely are the actual
width and number of her floats, paddle wheel diameter, sponson deck
width and thus BOP (Beam over Paddleboxes). In the absence of any
formal plans, maybe "Waverley" Mike (or anyone else) could step in
here and offer some inspired "guesstimate" as to the appropriate
float and wheel specs for a Clyde paddler of this length, vintage and
builder. At 180'6" and a hull beam of 18'2" (confirmed) she is one of
the smallest excursion service steamers built on the Clyde during
this period.

At this point I am purely estimating her wheel specs from scaled
photographs which I am listing as follows.

Paddlewheel diameter: 14'(est)
Float width: 5'(est)
Float depth: unknown
Float shape: concave/feathered (concave radius not known)
Float number: 7 or 8 (I really need this one confirmed!)
Sponson deck width: 6ft (est)
BOP: 30'2" (18'2" + 6' + 6')

Does Mike or anyone "Doon the Watter" have any comments which would
help me guess this as accurately as possible for, without plans,
that's all I can do ?

Regards
PJ
Victoria, BC Canada

[freedem]

--- In Paddleducks@y..., "paulrjordan" <pj@p...> wrote:
Two guess and they are ! wild guess! I've a gut feeling that most
feathering wheels had an even number of floats one bit of
research sugests that the radiour of the concave floats are the
same as the radious of the wheel.

no help but on american side wheelsers the drawing I have
found tend to have the width of the paddlewheels equel 25 to 35
percent the width of the hull so an 18 foot beam hull might have
wheels each 5 foot wide.( or 4.5 foot wide)

another rule I found in austrailian maurry river paddlers was that
the width of the wheel ( length of the floats) was 1/3 the dia and
height of the floats 1/3 the length) which would give length of
4foot 8 inches and height of 18 and 5/8ths.

[Derek Warner]

Jeffery - Mike Mayhew has posted should we say 'certain design parameters', but if you are interested in
building a model search the paddleducks messages for key words like 'paddlespeed' or 'paddlewheel'

I would suggest that most model paddle wheelers built or being built if not from plans, then would have been
scaled from photographs or sketches from archives [and this would include paddle wheel dimensions] - Derek