Pedal Powered Boats

Interesting Jeremy, thanks for that.

So, 4 watts, that's probably about 3 or 4% right?

100 degrees! Not 80 degrees right?

I wonder if I used two in series if I could get 80 degrees.

You know, this hardened steel is more brittle and prone to shear breakage from torque than unhardened steel. It's a little counter-intuative but I learned it the hard way and it's true.

 

Yes, the electric boat drive (not the one in the photos above) runs at 100 degrees, only because that made the height of the leg less, so it would fit (at an angle) under the deck, with the prop shaft horizontal. The biggest single loss was the lip seal on the output shaft, at around 2 watts. I found that getting low seal losses was challenging, the shaft needs to be highly polished where the seal bears on it to get the friction down. My best guess is that the double UJ itself may have been absorbing around 1 to 1 1/2 watts on its own, so pretty low, with the support bearings (4 ball races, shielded but not sealed) absorbing the rest.

The cordless challenge drive above is running at the tightest angle a double joint is specced to run at, 90 deg (45 deg per UJ). You may be able to run a double joint at a tighter angle, but it would be outside the limits that the manufacturers seem to spec for these parts. Might be worth experimenting with, if you're prepared to take a risk.

 

The u-joint adapters on my ratchet set at 18mm are very heavy duty and essentially bulletproof, waterproof, (chrome- vanadium steel) don't shatter like other hardened (can't be drilled with regular bit). But they would require some work to be adapted for a boat drive's shafts and don't have ball bearings... I'm wondering where are the 4 ball races (stress points?) are located on the units pictured.... Maybe parts of them could be used if they match up and some non-bearing parts are the failing...

P.

 

The UJs I used are Italian made units, from here: http://docs-europe.electrocomponents.com/webdocs/04c6/0900766b804c60b7.pdf (the type GD ones, with plain steel bearings).

The four ball races are on the shafts, two supporting the output shaft (on the oil filled side of the seal) and two supporting the input shaft (one at the lower end, next to the UJ, one at the upper end, adjacent to where the shaft couples to the drill).

You may be able to use socket set UJs, but my guess is that they won't be very accurately made or well-balanced, which may create problems

 

Hey guys, remember me? If not, I quoted a couple posts at the end to remind you

The weather finally seems to have got nice around here for good. I've finally got in a good ride in on the ol' analog bicycle aka real bicycle out on the road.

I picked a route that google maps tells me is 11.9 miles. It was a mostly flat out and back loop basically. On incline kinda snuck up on me and kicked my butt but I ended where I started so it should even out. It wasn't a continuous ride, there were a few stops to obey traffic signs and wait for traffic so I could make a turn and what not, but not too bad.

The stop watch says it took me 49:14 for the ride which I'm just going to round to an even 49min since the 14s is about the time it took me to pull my phone out of my pocket and turn off the stopwatch. 11.9 miles in 49 min is an average speed of 14.57 mph

I plugged all the right information into the calculator provided by coach Dave (http://www.kreuzotter.de/english/espeed.htm). I selected the mountain bike (MTB) with robust wide touring tires selected rather than the MTB tires because I swapped my MTB tires for treaded "hybrid" tires since I do most my riding on road or hard packed bike trails but I checked and there was really no difference between those and the MTB tires anyways. Put in my height (76in) and weight (375lbs) and took a guess at everything else but really aside from heigh and weight the rest doesn't seem to make huge differences so I figure they're close enough.

When I hit calculate it tells me *drumroll* 187 watts. Which is actually not far off to the *long* rides I've been taking on the exercise bike. Considering the start and stops, and the differences between riding a recumbant stationary bike and an upright real bike, and the fact that this was my first real good ride on the bike in a while, I'm going to stake claim to 200W as a good target design input wattage. Sound fair?

What do you guys think should be the next step in this design process?

 

Hi Rhinox,

Welcome back.

Of course I remember you.

I think "the next step in the design process" should be buying yourself a one or two seater row boat with sliding seats. You're going to work the greatest number of muscle groups that way, work at your peak performance and be able to easily modulate your level of effort tailoring your workouts.

You'll enjoy fishing from a rig like this, have room for an extra rower as needed and enjoy the seaworthiness of such a craft.

Good to see you back still full of piss and vinegar!

 

Rhinox
If you go ahead as Tom suggests and get a rowing boat then its only a small step to make it into a pedal boat. A bike crank and pedals with the chain running to a 90 deg gearbox mounted on the side. Then a flexible shaft with prop hanging over the side, see setup Rick uses on his boats. You can maximise the speed if you play around with the gear ratios and prop sizes.

Ian

 

Tom: So... maybe something like this?
http://www.adirondack.net/commonimages/businessslideshow/5437-2478-090812144031-5905.jpg

Or maybe this?
https://www.glen-l.com/picboards/picboard15/pic766-11.jpg

(just google searched for pics)

Yeah I mean I've certainly thought about it before. Something different than I'm used to (rowing), gets me out on the water quicker. I've actually leaned more towards a touring kayak than a rowing shell because it seems like it would be nicer to face forward and see where I'm going. Most of the time it would probably be just me, but I guess my wife might be interested coming out with me every once in a while. We could even bring the dog and make an afternoon out of it. Are seat positions easily adjustable in these boats? For example would I be able to find a 2-person where I could remove 1 seat and move mine to the middle for when I'm the only one? Are these boats also going to be able to handle a little bit of Lake Erie chop?

I57: yeah I really like the over-the-side flexible shaft setup. Clean, relatively simple, minimized resistance. I've humored the idea of picking up a cheap used canoe off craiglist or something and modifying it for pedal power just like that.

 

Sure, those look good.

Whitehall is made here in my hometown and they export around the world. A little more robust. How big is your dog? I don't know about seat adjustment/relocation, you'd have to look on their web-site. Maybe two boats is the way to go. One for just you and a family boat. I believe the important thing is to get you on the water. I can certainly appreciate wanting to face forward. A kayak style would be great for that and easily modified to pedal power. That's what I'm in the middle of doing with a surf ski.

 

a surfski? hopefully a stable one? outrigger? Pics?

 

It's not stable at all, although it does have a 1.5 meter winged keel with a 65 litre bulb on the end of it. The bulb floods and purges according to velocity. The hydrofoils are servo controlled to regulate roll once making way. I'm not quite at the publish stage yet but depending on current life events I may have some pics to show soon.

How's your project coming?

 

a quick summary: I've backed off the cat idea a bit to pursue the proa tangent and still working out the details but had to get back to my main project right now. It's a stripper canoe that you'll be just dying to know more about but it's not related to this tread at all. Details coming at a future date, but hopefully not too far away!

 

Hello Rhinox!

There is a boat covering just what you need: the VirusBoats Yole. Can go with 2 persons and a dog and can go with you alone. Seems to be very stable and dry.

I would have already bought one of these, if they were only built with pedals instead of oars

 

Rhinox,

I found the web-site if you're interested:

www.whitehallsolo.com

 

Thanks. I checked out the site and googled and found lots of other really nice options. Lots of good stuff out there, but it's all so expensive. I'm not really willing to drop that much $$ into a boat right now. Even if I could build a plywood shell for free, the sculling rig and oars are gonna push me out of my desired budget.

I'm thinking like, under a grand is where I'd like to be, and I don't think I'm gonna get there without DIY and pedal power, or finding a really extraordinary deal on something used.