Paddle wheel help

Im in the process of completing a 17’ sidewheel paddle boat. In the testing phase trying to work out the bugs of it. Took it out today onto the lake. It was a bit gusty and had a hard time fighting the wind with the paddle system. I have 6 paddles and they dip into the water about 5 inches. My thought is I need more paddles on the wheel and/or deeper wider paddle blades. (The blades are 12” wide). Would love to hear some insights or ideas. Thanks!!

 

Not enough information.
This is a world wide web.
Many, many cultures here.
Drawings, sketches, plans, pictures, measurements, more info.

What does "a hard time" mean?
6 paddles total, 3 on each side wheel?
Did you do any research beforehand, where?

Paddle wheels are great.
What powers yours?
What's the boat made of?

More info please.
What kind of problems are you having?
What have you done to fix them?

Have you used the search engine here on the Forum?

 

Six is nowhere near enough, especially if they are not feathering. (and FWIW, they are called floats) On the web you can find a PDF of Hydrodynamics in Ship Design (SNAME, Saunders, 1957), you want Volume 1, Chapter 71.

 

Hey guys good challenges. So “hard time” meant I was pretty much standing still in the water when trying to go upwind. To paint the picture there were 19mph gusts per the forecast. 6 floats on each side. I have a 6.5 predator motor powering the wheels via a chain drive to a transmission and then onto a solid shaft. It’s a fiberglass P17 sailboat hull. I have done some research on here as well as on the web just that every boat seems to be different and not many like mine as far as size/design

 

G4S your boat has a lot of frontal area. That includes the mast and paddlewheels as well. In 19 mph gusts, there will be a large opposing force working against your forward progress. You need more propulsive force to counteract all that wind resistance.

Jehardiman is one of our go to guys. If he says more "floats" then add more floats. There are more variables, such as the speed (RPM) of the wheels. All sorts of stuff factors into an efficient paddlewheel layout, such as the depth of immersion of the floats. You will have fun sorting those things out. I notice that the wheels have no cover outside of the floats. I suspect that part of your thrust will be affected by the cover or absence of it. The word, cover, is to mean a doughnut shaped disc at the outer edges of the paddles....er... floats. That doughnut will also stiffen the floats such that they do not deflect backward during the power stroke.

Good luck with this project, it is a whole other way to propel a boat, though not an ultimately efficient way.

 

My tiny paddlewheel (sternwheel) dinghy has a 17.5" wide wheel dipping it's 6 vanes around 5" into the water. It works very well but it sounds to me like your propulsion is nothing like what's needed. You want as little slippage through the water as possible for efficiency. I can't give you the dimensions you need but clearly they need to be vastly bigger. Width is probably your biggest friend. https://mountainbiker.online/2021/10/26/cross-training/

 

I think you guys are definitely on to something about more floats. I’m thinking about it today I think I want to weld more square stock steel in between the current floats to double the amount floats. The donut idea is interesting....the floats as they are are pretty stiff they are mounted on 2x2 pressure treated wood socketed in the aforementioned square stock but I’m definitely open to the donut idea. Previously I had the floats deeper and wider. That seemed to work except it put too much strain and slipped the clutch I had on the motor. I’ve since switched it out with a torque converter which I feel might handle the extra strain much better. I do really appreciate the ideas. I’d love to get this thing working reliably.

 

I don't know diddly about paddle wheels. I will comment that your house looks like it was not designed with wind in mind. Between the high bows and high house and roof overhangs; the windage is considerable as well...not to mention the mast. Does it still sail then as well? Or is the mast retained for stability only?

 

In the pic it appears that with just a small amount of heel the upside floats come out of the water, or are just barely submerged.
Five inches is not enough, and 6 floats are not enough.
With only 5 in. in the water just small wavelets will be enough to affect the amount of useful thrust you'll get.
Paddle Wheel propulsion can be reasonably efficient at low speeds, given enough submerged float area and the torque to drive them.
You need enough floats so that their is no "gap" in time between a float leaving the water and another entering the water.

 

Ok, sorry, I misinterpreted that pic.
Blowing up the pic a bit, it does appear that the upside floats are still in the water.
So, you might be ok with 5in immersion.
If you draw a circle representing the OD of the wheels, and draw a line representing the WL (a chord of the circle,) you'll see the underwater area you have to work with.
For small boats a decent starting plan is with one float at max thrust, (vertical position,) the retreating float is just about out of the water, and the advancing float is just about entering the water, so that at any one moment their are 2 floats in the water.
That gives more continuity of thrust.

 

I left the mast on for stability although it’s cut down from what it was. Also the anchor line runs up to the top and down to the bow so that the anchor can be dropped and pulled up from the stern of the boat. I do think you guys are on to something with adding more floats. I’m hopping I have time in the next few days to pick up some square stock and weld some more float holders to the wheel. That would double the number on each side. Also I like the idea of making the paddles a bit wider and deeper.

 

Paddle Wheel propulsion has always interested me.
Many years of sailing/boating on the Columbia/Willamette rivers and reading/researching the rich history of the area and its use of stern-wheel boats for navigation nurtured my imagination for designs in that vein.
One of my pet ideas was to get one of the old "Cruise-a-Home" houseboats, and with a some cutting, and fiberglass re-do of the aft sections they can have a stern section that is quite adaptable to paddle wheel propulsion.
My sketches/drawings worked out to a stern wheel ~8ft diameter by ~8ft wide.
At low speeds a well-engineered stern wheel can have a surprising amount of thrust.
For decades the steamer "Portland" was the most powerful tug on the river, they even sent her downstream once to pull off a grounded ship that propellor tugs were unable to do.
At lower speeds it's about the mass of water you can move, can props do it, sure, but they have no romance.

 

^^ Mast is left in place to improve stability??? It may help stability if the mast carries a riding sail. If there is no sail, I suggest that stability is less, not more. Weight aloft will influence the roll of the boat which is not ideal for a paddle wheeler. If you have the anchor rode running to the top of the mast you are setting yourself up for trouble. In fact, when we want to careen a sailboat, attaching a line to the top of the mast is a common way to do it. The mast acts as a giant lever

 

I don't doubt that has been your experience messabout, but it's not always the case.
Sometimes, stability and sea-kindliness is improved by leaving the mast up.
Or, reducing it by half, like in this case.
The OP may already use a steady sail (riding sail).

My point is, blanket mast height statements like this are design dependant.

 

Have been running a 19ft - 3 inch sidewheeler for over 10 years, look up sudewheel steamboat ob youtube. Lots of info on thesteamboatingforum.net Glad to help with design details if you like.