Where to start on a pedal powered boat?

[alexlebrit]

Interesting about the paddle wheels, I think I'd thought like many people that they were an outmoded form of propulsion, but it looks like they have a lot of advantages.

So, I'm wondering what could be the best design of wheel both for aerodynamics and hydrodynamics.

[Guest625101138]

Originally Posted by alexlebrit

Interesting about the paddle wheels, I think I'd thought like many people that they were an outmoded form of propulsion, but it looks like they have a lot of advantages.

So, I'm wondering what could be the best design of wheel both for aerodynamics and hydrodynamics.

Be aware that with paddlewheels big is beautiful and the only way to get efficiency.

On an easily driven hull like my V11 you need wheels around 4ft diameter and blades on each side wheel of 2ft wide to exceed 80% - quite large. Blades would be about 90mm deep with a slight aft rake. You want lift and clean exit rather than sinkage and water wheel. I do not think articulated paddles are worth the effort or extra weight. They can give a slight gain in efficiency.

They would need some sort of fairing if you wanted to reduce windage but it is not a killer.

Rick W

[clmanges]

I'm investigating conical paddlewheels; see

Pedal Boat Design

I've barely started working with the design concept, so I can't tell you much yet.

Curtis

[tinhorn]

Oops. I just posted a PDF on that thread containing some old feathering patents. Tough keeping the two pedal boat threads apart.

Anyhow, with apologies for not cleaning up the pages, and for excessively reducing the file size, I offer you cutting-edge 1800s paddle wheel technology.

[ryan808]

Originally Posted by Rick Willoughby

A 16X16 APC prop will work OK.
A decent right angle drive is a good investment. If you cannot afford the 200+ dollars to get one new have a look on Ebay. I know a fellow who got three nice little boxes for USD100.

If you have a gearbox, you can use a cutdown bicycle frame with the bottom bracket upwards as the crank support. Just need a plate welded or bolted on to carry the gearbox. The gearboxes have numerous mounting points; unlike the Sears drill stuff.

You need to do some planning and have an idea of what you can spend on the project. You can waste of lot of time, effort and money for the sake of planning what you really need, to achieve what you aim for.

Rick W

Rick W.
Is there a better prop? What kind of right angle gear boxes should i be looking for? I don't know the difference from one to the next. I'm not entirely certain that I understand the bike modification suggestion...
ryan

[Guest625101138]

Originally Posted by ryan808

Rick W.
Is there a better prop? What kind of right angle gear boxes should i be looking for? I don't know the difference from one to the next. I'm not entirely certain that I understand the bike modification suggestion...
ryan

In my very early post I gave a link to a Mitrpak box. This will give you an idea. There is also similar boxes in the link you were provided for Mcmaster.

You want a box with 1/2" shafts. 3/8" could be made to work but the chainring required for this is not easy to come by. Best to go for 1/2 or 5/8 shaft ans tick with input gearing in the range 3 to 4:1.

The Mitrpak box have stainless shafts, which is a benefit for use in salt water.

Rick W.

[magnus]

Alan White suggested a Milwaukee angle drive on this thread and I reccently joined this forum and have experience with that drive. I ran a 46/10 chain drive to it. From there you have the option of 2/3 or 3/2 for final speed by flipping the drive. I went with 2/3 and several props: 14x14 ACP and homemade: none worked better than the bow facing rowing system I had originally, but the props, angled shaft, and oversized (1/2inch diameter) shaft were probably at fault. This was 15 years ago and I was shooting from the hip. Rick's flexible smaller diameter self aligning shaft with a proper Java designed prop will work better. The drive has sealed ball bearings on both ends and is supported internally by borings for both shafts into the aluminum housing. I dissasembled it and noticed no wear in the limited hard use I gave it. When I bought it for 60 dollars US the local service center would rebuild it for 30 dollars US. Attachments at both ends is standard drill chuck in the US, I believe 1/2 US fine thread. I can put some pictures of the drive on if their is interest. Looks like 90 dollar US will buy it today and that heavy pinch coupler that comes with is not nessecary, use 2.00 inch/.058inch wall 6061 T6 aluminum at whatever length you want from the hull, slit the end and a stainless worm gear/hoseclamp will pinch it tight, may need a wrap or two of tape on the drive before you slide it in.

Jim

[magnus]

I have ever given and it goes by the wayside