Requesting Small Sternwheeler hull design and analysis help

[phrogjlf@yahoo]

BTW, phrogjlf, here's an outline of what I'm leaning towards in a paddlewheel boat.

http://www.boatdesign.net/gallery/showphoto.php/photo/24218/ppuser/54771

That rear deck, where you're putting the wheel looks a lot like the one on a Lafitte Skiff...

Matter of fact, the outline could have come from one, though the Lafitte Skiff has a V bottom.

Wish a flat-bottom would work, here. It would be a lot easier to build.

 

[Rurudyne]

Funny, my thoughts had earlier been that the Lafitte Skiff looks like it may have been influenced by paddlewheel boats.

 

[rangebowdrie]

One of the big problems with small sternwheel boats is getting enough area
on the floats,(paddles). When pittman arm drive is used, you must use two, at 90 degrees from each other to eliminate "dead centers".
For effective drive, the wheels need to be as wide as possible, the drawings
you see of 8ft wide boats with two wheels, each only a couple of feet wide, end up operating like a "water wheel" at a grist mill, nice to look at, but without much real thrust. With an 8ft wide hull, try to get a single wheel of at least 5ft wide, whose floats operate at not-quite full immersion.
For good operation you need rudders both in front of, and behind the wheel. The rudders ahead of the wheel need to fill the roughly trianglular area that is between the up-sweep of the hull, and the wheel, three rudders work good. Using linkage, connect the "monkey rudders", (the ones behind the wheel,,can use two), to follow the mains.
Don't worry about directional control, if you use a set-up that will alow you to operate the main/monkey rudders independently of each other, you will be able to vector the wheel thrust in a wide swath to either side, both astern and ahead. Back in the day, watching the steam sternwheeler Portland muscle ships around in crowded areas with only one wheel, would give you an idea of just how paddle wheels work. They can be quite powerfull at low speed.

 

[Rurudyne]

I recently posted a DelftShip produced image a shallow draft sternwheel boat that going by its drag calculations should require about 3.8 HP to push the thing to 6.3kt.

Working with Seaton's Rules, available as a free PDF from Google Books, the size of wheel in that picture would run around 62 rpm with 30% slip (assume the worst, hope for the best). That would translate into the floats, 7 floats per wheel, being 26.2" x 6". Seaton's rules appear to be for sidewheel boats so a single sternwheel twice that or twin stern wheels of that should satisfy.

Even though Catfish is only 7' in beam it would still be possible to use twin sternwheels, though that speed would require the operating depth of the wheel be increased by 2" or so from the position shown to achieve that (thus my interest in adjustable height). Naturally, a wider/thinner float and one wheel would be a lot less complicated and probably be the way to go.

More to the point, back off the expected speed and the twin wheels quickly become doable even without adjustment.

 

[phrogjlf@yahoo]

For mine, I was aiming at a pair of 30" wide, 6' diameter wheels, and 8 floats (diameter, plus 2 floats rule-of-thumb). Figure 6" outside arms and a 14" central one, with a touch of side clearance.

I had planned for rudders and the possibility of monkey-rudders, though I may not have mentioned it.

Once I get a water-line on the actual hull, I'll set the flat depth, to clear the lowest point of the hull, up to the waterline, plus about 1/3rd more above the water-line.

Right now, I'm working up a simple hull to build, for a practice-run, before I start the model hulls for comparison. Simple stitch-n-glue SUP design, for experience, then move forward. Don't think I even ever made paper boats, as a kid.

 

[rangebowdrie]

The nice thing about monkey rudders, is since they are so far aft behind the hull, they have great leverage for turning, and the main, (forward), rudders work very well for directing the thrust when going astern.
What you don't want is sponsons alongside the wheel, they act as long rudders extending aft of the hull, and reduce manuverability/turning ability.
A 100 and some years ago, there were scores of little sternwheelers operating in all the tributaries of the Wilamette/Columbia rivers, some as small as 30ft., many times they backed up small streams to get to places where they would not be able to turn around.
Given enough float area, they are quite agile, there is no "walking" of the stern, either ahead or astern,,they go where you point them.
Get the sharp cutwater to flare-out quite quickly to a flat bottom, and get the flat bottom to rise-up, and clear the waterline at the stern,, slab sides, perhaps curving inward a bit at the stern, to match the wheel, (in plan view), and you can't really go very wrong.

 

[Rurudyne]

Actually, the monkey rudders are more for backing up. I know this sounds looney but for some reason with paddlewheels it's pulling water across a rudder that makes it effective rather than pushing it past (as props do) that makes the thing work. Or maybe props work that way too but it's just too easy to put them after the wheel. Hey, who says physics actually has to be consistent?

 

[Rurudyne]

And while we're at it check out those groovy bow mounted rudders on some paddlesteamers!

 

[Rurudyne]

This is one reason why I get headaches....

 

[rangebowdrie]

Whether by ahead or astern, rudders are more effective when within the area of water flow that is being accelerated at a faster rate than the speed of the vessel.
Here's a couple of small boats;
https://www.youtube.com/watch?v=-bQJOxwpzeQ
https://www.youtube.com/watch?v=CtgDvKOf0iI

And for a more stately vessel, that I'am quite familiar with;
https://www.youtube.com/watch?v=cQecwRr3U3o

 

[Clyde2001]

Hull shape

Jeff,
Most of the old stern-wheelers on the Mississippi were pretty much flat bottomed but your shallow v will give you better tracking in the wind. Not that paddle-wheelers are all that great in a wind. Since your wheel and rudders are normally above the bottom of the boat, For a smaller boat, a scow hull would probably work as well as any, just make sure to have sufficient stern rake to allow a smooth flow of water to the wheel or wheels. Typically your rudders fit in the rake. Unlike a propeller driven vessel where the prop pushes the water by the rudder in a stern-wheel boat, the rudders ahead of the wheel are the mains and operate by directing the water into the wheel. The water behind the wheel is mostly foam and the rudders (monkey rudders) aft of the paddle-wheel aren't real effective unless you are backing.
If I had it to do over again, I would definitely go for independently driven split wheels. Much easier to handle in a tight spot.

 

[SamSam]

Jeff,
Most of the old stern-wheelers on the Mississippi were pretty much flat bottomed but your shallow v will give you better tracking in the wind. Not that paddle-wheelers are all that great in a wind. Since your wheel and rudders are normally above the bottom of the boat, For a smaller boat, a scow hull would probably work as well as any, just make sure to have sufficient stern rake to allow a smooth flow of water to the wheel or wheels. Typically your rudders fit in the rake. Unlike a propeller driven vessel where the prop pushes the water by the rudder in a stern-wheel boat, the rudders ahead of the wheel are the mains and operate by directing the water into the wheel. The water behind the wheel is mostly foam and the rudders (monkey rudders) aft of the paddle-wheel aren't real effective unless you are backing.
If I had it to do over again, I would definitely go for independently driven split wheels. Much easier to handle in a tight spot.

Hey "Clyde", welcome to the forum.
I posted to you a long time ago and never heard back, but I was wondering if this was the Clyde that one of your relatives used to run up there?

Title: Clyde (Rafter, 1875-1941)Description: BOAT DESCRIPTION: Sternwheel
BOAT TYPE: Rafter/Towboat
FORMERLY: Clyde (Sidewheel rafter/towboat)
FINAL DISPOSITION: Dismantled, 1941
OWNERS: 1875: Captain J.M. Turner and Captain A.F. Hollinshead; 1886: Turner and Law of Lansing; 1895: Captain Frank Fugina of Winona, Minnesota; by 1919: Arrow Transportation Company; by 1941: Tennessee Valley Sand and Gravel Company
OFFICERS & CREW: 1875-1884: "Dick" Dixon (Dickson?) (pilot); 1889-1895: Captain Merrill Looney (master/pilot); 1896: John Hoyt (captain), Milt Newcomb (engineer), Sam Serene (2nd engineer); 1897: Frank Wittenhall (pilot); 1898-1910: Captain Isaac Newcomb (master/pilot); 1928: Captain J. Wylie Leek (master), Frank Voight (pilot), Boyd Hardesty (chief); 1933: Captain Frank Voight (master), George Smith (pilot), Jesse Dougle (chief engineer)
RIVERS: Mississippi River; Tennessee River; Ohio River; St. Croix River
OTHER INFORMATION: Ways - T051; The sidewheel rafter, Clyde, was converted in 1875 to a sternwheel keeping her name. The conversion was done at Dubuque, Iowa by Captain J.M. Turner and Captain A.F. Hollingshead who ran logs for the Empire Company and the Standard Lumber Company. While under the ownership of Captain Frank Fugina, she was chartered to the United States Engineering department. When Arrow Transportation Company bought her, she was transfered to work on the Tennessee River. On November 12, 1919, the Clyde made a trip to Pittsburgh to tow new Allegheny River barges south. On November 9, 1933, she sank at Paducah, Kentucky in wind swells. Arrow Transportation Company was planning on abandoning her at that time but changed their minds and rebuilt her. Sold to the Tennessee Valley Sand and Gravel Company, she made her last trip in October, 1941. At that time she was cut down to a single deckLCSH Subjects: Towboats--Mississippi River / Towboats--Tennessee River / Towboats--Ohio River / Towboats--St. Croix RiverSubjects: Sternwheel raftersIdentifier: Neg. 33830Is Part Of: UW La Crosse Historic Steamboat PhotographsRights: This image cannot be copied or reproduced without the permission of the University of Wisconsin-La Crosse, Murphy Library, Special CollectionsSubmitter: University of Wisconsin-La Crosse, Special CollectionsNote: Clyde (D)Local Identifier: LaCrosseSteamboat.steam04308.bib

 

[phrogjlf@yahoo]

Jeff,
Most of the old stern-wheelers on the Mississippi were pretty much flat bottomed but your shallow v will give you better tracking in the wind. Not that paddle-wheelers are all that great in a wind. Since your wheel and rudders are normally above the bottom of the boat, For a smaller boat, a scow hull would probably work as well as any, just make sure to have sufficient stern rake to allow a smooth flow of water to the wheel or wheels. Typically your rudders fit in the rake. Unlike a propeller driven vessel where the prop pushes the water by the rudder in a stern-wheel boat, the rudders ahead of the wheel are the mains and operate by directing the water into the wheel. The water behind the wheel is mostly foam and the rudders (monkey rudders) aft of the paddle-wheel aren't real effective unless you are backing.
If I had it to do over again, I would definitely go for independently driven split wheels. Much easier to handle in a tight spot.

Thanks. Things are on hold... Possible land deal, with a huge shop...

Welcome to the forum! If you're on Facebook, there's the American Sternwheelers Association group, if y'all are interested...
https://www.facebook.com/groups/121322807938030/

While a flat-bottom would usually do, this place has muck that I've seen stick down flat-bottoms, then the rising river just drowned them. A shallow V with rocker would try to lift the higher point, or side first, automatically helping work it free, even if nobody is there, when it happens.

When/if I get the other place, I'll have access to several lakes, rather than the Colorado River, but, after all this trouble, I'll be damned if I'll simply toss the project. Even found a few that aren't in this thread, that may be better hull designs, but retain that general layout. I could care less if anyone ever understands her name, but, maybe I'll get her down here, sometime, as well.

 

[fredrosse]

Speaking on direct 21st century experience with a few paddlewheel boats: If you have two independent stern paddlewheels, monkey rudders will not be required.

 

[Clyde2001]

Yes, that is a photo (nice one by the way!) of the original Clyde, either in her second or third configuration. She was originally built as a side wheel packet in 1870, rebuilt as you see her here in the early 1880's. My Grand-dad Frank was Pilot on her during her years of rafting. His Brother Ike as Captain and Milt was engineer.

My little Clyde. was a 50' diesel hydraulic drive. Displacement of around 15 tons, she was powered by a 36 hp. Kobota diesel. Experts on this site have claimed that hydraulics were not efficient, but this boat proved pretty handy and could run all day at 8 knots, burning about a gallon per hour. She is currently on the Ohio, and can be seen on Facebook at Rafter Clyde, or Rafter Clyde II.

Speaking of monkey rudders, I had a set on this boat when she was built and took them off, never did get them sorted out. She did have a hydraulic bow-thruster however and this proved really useful. With a paddle wheel, if the wheel is not turning, you have NO turning ability, regardless of how many rudders you have.