Pedal Powered Boats

[portacruise]

Dennis
I get range 2 of the wire specified on the linked page:
http://www.onesteel.com/products.asp...ire%20Products

I have used up to 10mm. It is surprising how low the shear stress is for the torque on shafts. Most prop shafts are sized on critical speed. If the shaft does not have a long unsupported length in air then critical speed does not come into consideration; at least for small diameter.

I paint the shafts otherwise they rust. I have considered using the spring steel as the former for wrapping layers of glass tape and epoxy so the steel is protected from corrosion but never got this far. Paint lasts a few years if you treat the shaft carefully. I store them under cover. I have a quick, no tools connector so I can remove them for transport. It also overcomes the problem of the prop spinning in the wind as I drive.

The spring steel is very tough and hard. It can be bent at tight radius. It is almost impossible to drill. I have managed to cut a partial thread but I destroyed the die. I have devised different methods for clamping. The easiest is to grind a flat and tighten a grub screw on it. The torque is rarely a constraint for me. It is the torsional stiffness so having a connection that creates a torsional stress raiser is not a problem. There are a couple of ways to connect to avoid a stress raiser.

Maybe you've tried a Dremel tool with diamond bits already, for working hardened steel. Anyway, I have had good luck with these though they generally wear quickly so you may need a dozen or so to complete a job. The good news is that they are now very cheap in bulk coming in from Asia.

Vic

[Rnykster]

The Hobie sets the current standard in pedal boats. They are rubbish from a performance point of view. Most people do not realise it until they compare the Hobie with something else - even a good kayak.

I recently participated in a local kayak race with my Hobie pedal boat. Out of about 120 racers, my pedal boat came in 15th. I was trying to keep up with a guy in a surfski, which I did for about 45 minutes, but he speeded it up and came in 3 minutes ahead of me. This was about a 10 mile race and I finished in 1:49 with an average speed of 5.3 mph overall. There were a lot of kayakers in "good" kayaks, in disbelief that a old man in a Hobie pedal boat came in before them. To say Hobie pedal boat performance is "rubbish" is not true.

The reason pedal boats have not gained wide popularity is they have no organization or racing committee, not to mention lack of product and distribution. I wanted to try out a Cadence but there wasn't a single one available to try out within a thousand miles. (The company is now for sale.)

Kayak fishing is relatively new. Clubs have formed. Clubs put on fishing tournaments. Sponsors have jumped in and support the clubs. A nearby kayak fishing tournament scheduled this spring has about 7 award divisions and the first prize award for each fish division is a brand new kayak. Wow, talk about an incentive to get involved in kayak fishing... I imagine if there were pedal boat clubs that hosted races and with help from sponsorships, had new pedal boats as prizes, that a lot of people would break away from bicycle racing and join pedal boat clubs. What did I get for being the first pedal boat to cross the finish line in the race? Nothing...

The quality of Hobie pedal boats have steadily improved over the past decade and they are now widely distributed with increasing sales. There is nothing stopping people from organizing racing clubs and hosting races. If there were clubs and races, then sponsors would step up with nice prizes. Pedal boat racing is up to the people, not the manufacturers.

A person can get just as much of an aerobic workout in a 12' long pedal boat as they can with a 21' long pedal boat. While speed is great for those like Greg wishing to break world records, the MAJORITY of people will never seek to race in that category. Runners have age group divisions in their races. Kayak racing has boat divisions and age divisions. Pedal boats should have their own boat divisions and age divisions to encourage everyone to participate but without clubs hosting races and governed by some sanctioning organization, they are left competing with surf-skis.

Performance is up to the individual in their type of boat and age division. To say Hobie, which you admit, sets the standard in pedal boats, has lousy performing pedal boats is rubbish and is only exacerbating the problem of pedal boat racing ever gaining any acceptance.

[portacruise]

Good post. I might add that the Hobies are better in weed situations. OTOH, speed is accomplished because of efficiency, so an advantage of a faster boat is increased range at less effort which is generally a plus for most. I would go for a trade off that is much more compact and stable than a racer design, for what I do though.

Porta

=

Originally Posted by Rnykster

Hi Rick - I recently participated in a local kayak race with my Hobie pedal boat. Out of about 120 racers, my pedal boat came in 15th. I was trying to keep up with a guy in a surfski, which I did for about 45 minutes, but he speeded it up and came in 3 minutes ahead of me. This was about a 10 mile race and I finished in 1:49 with an average speed of 5.3 mph overall. There were a lot of kayakers in "good" kayaks, in disbelief that a old man in a Hobie pedal boat came in before them. To say Hobie pedal boat performance is "rubbish" is not true.

The reason pedal boats have not gained wide popularity is they have no organization or racing committee, not to mention lack of product and distribution. I wanted to try out a Cadence but there wasn't a single one available to try out within a thousand miles. (The company is now for sale.)

Kayak fishing is relatively new. Clubs have formed. Clubs put on fishing tournaments. Sponsors have jumped in and support the clubs. A nearby kayak fishing tournament scheduled this spring has about 7 award divisions and the first prize award for each fish division is a brand new kayak. Wow, talk about an incentive to get involved in kayak fishing... I imagine if there were pedal boat clubs that hosted races and with help from sponsorships, had new pedal boats as prizes, that a lot of people would break away from bicycle racing and join pedal boat clubs. What did I get for being the first pedal boat to cross the finish line in the race? Nothing...

The quality of Hobie pedal boats have steadily improved over the past decade and they are now widely distributed with increasing sales. There is nothing stopping people from organizing racing clubs and hosting races. If there were clubs and races, then sponsors would step up with nice prizes. Pedal boat racing is up to the people, not the manufacturers.

A person can get just as much of an aerobic workout in a 12' long pedal boat as they can with a 21' long pedal boat. While speed is great for those like Greg wishing to break world records, the MAJORITY of people will never seek to race in that category. Runners have age group divisions in their races. Kayak racing has boat divisions and age divisions. Pedal boats should have their own boat divisions and age divisions to encourage everyone to participate but without clubs hosting races and governed by some sanctioning organization, they are left competing with surf-skis.

Performance is up to the individual in their type of boat and age division. To say Hobie, which you admit, sets the standard in pedal boats, has lousy performing pedal boats is rubbish and is only exacerbating the problem of pedal boat racing ever gaining any acceptance.

[Guest625101138]

Originally Posted by Rnykster

..... There were a lot of kayakers in "good" kayaks, in disbelief that a old man in a Hobie pedal boat came in before them. To say Hobie pedal boat performance is "rubbish" is not true.

......

The performance is relative to what you compare it to. The best performing long-distance pedal boat is the V11 design that Greg used for his record. The fastest sprint boat is the Decavititor. Over 2000m, rowing sculls come into the picture.

Each year I do a long-distance race and rank reasonably well against some vey good engines in paddled craft. There have been two years when Hobies have competed and they have not made the closing time on most days and get picked up by the sweeper boat.

The Cadence is the best engineered commercial boat and does quite well. If you do get a chance you should try one to get a feel for a boat that goes well. I find them a bit tippy but I am used to very stable platform. Mike Lampi may be able to arrange a ride with someone near you.

The Hobie over-centre pedal action is quite awkward compared with a crank. You might get used to it but there are much smoother actions.

There is not much around to compare with the Hobie but their performance is rubbish compared with perfamce HPBs as your experience with the surf-ski suggests. The Hobies are well suited to their market but they perform badly against performance craft like surf-skis, racing kayaks and rowing sculls. One advantage of the Hobie is that they require little technique. A person of average fitness can move quite well compared to what they could in a paddled or rowed craft.

You are right about the growth for fishing kayaks. If this market grows there may be more opportunity for performance craft and something different may get a hold. Right now Hobie have a strong position.

[Jeremy Harris]

I'd be interested to see a direct comparison of different human power application methods, rather than some of the apples & oranges comparisons that are unavoidable with the limited number of HPBs around.

What, I wonder, would be the outcome of this experiment:

- Take three identical hulls, one paddled as a kayak, one fitted with the Hobie flappers and one fitted with an efficient propeller system.

- Each would be crewed by people of identical fitness level (each skilled in their particular crafts propulsion system operation) .

- Let them all go head to head in a race around a triangular course (so each gets to operate in differing wind, wave and current conditions).

- Let the race be long enough to test the average power output of each crew, rather than their peak output.

Which would turn out to be the fastest, and hence most efficient, propulsion system, I wonder?

I would guess that it'd be a close run thing between the paddler and the propeller, with the Hobie system coming last, but it would be interesting to know for sure.

Jeremy

[portacruise]

Interesting experiment. Under perfect, ideal, conditions (NO WEEDS), clear water, no obstructions, the prop boat would be the best in both speed and range IMHO. That experiment can be done with the SAME hull in protected water tank testing and measured watts output which might be better than a triangle course, because it eliminates even more of the variables. Human output itself can vary tremendously even for the same human athlete, depending on psychological, chronological daily rythms, what else is going on in their life, etc. Paddling would be a distant second. Only the special unique skill of an experienced operator would be overlooked.

By the way, what you propose has been something I have favored when competing for world records in any sport. Record speed crossing the English channel has little meaning for example, because so much depends on chance...

Porta

Originally Posted by Jeremy Harris

I'd be interested to see a direct comparison of different human power application methods, rather than some of the apples & oranges comparisons that are unavoidable with the limited number of HPBs around.

What, I wonder, would be the outcome of this experiment:

- Take three identical hulls, one paddled as a kayak, one fitted with the Hobie flappers and one fitted with an efficient propeller system.

- Each would be crewed by people of identical fitness level (each skilled in their particular crafts propulsion system operation) .

- Let them all go head to head in a race around a triangular course (so each gets to operate in differing wind, wave and current conditions).

- Let the race be long enough to test the average power output of each crew, rather than their peak output.

Which would turn out to be the fastest, and hence most efficient, propulsion system, I wonder?

I would guess that it'd be a close run thing between the paddler and the propeller, with the Hobie system coming last, but it would be interesting to know for sure.

Jeremy

[Rnykster]

Originally Posted by Jeremy Harris

...I would guess that it'd be a close run thing between the paddler and the propeller, with the Hobie system coming last, but it would be interesting to know for sure. Jeremy

Jeremy - if that was the case, then why, in a recent race, would a 27.5 inch wide plastic Hobie pedal boat beat the majority of paddlers in much narrower 21 to 25 inch wide fiberglass kayaks? It almost beat a tandem team in a fast 20 inch wide fiberglass kayak 21 feet long. The Hobie Mirage drive system is more efficient than the paddle system because it utilizes a more powerful muscle group. If in comparable boats, Hobie would always be faster than a paddler. I can't paddle my Hobie kayak as fast as I can pedal it.

What few propeller boats that are available in this area (Native Watercraft), don't stand a chance against a Hobie. When better propeller boats are manufactured and distributed, I'll try one. Until then, Hobie pedal boats are the winner.

Rick suggested that I should try the Cadence. I'm aware of Michael's use of the Cadence in many races and have asked Michael several times in the past, to hook me up with a Cadence. No dice. I've basically got to travel 3000 miles to try one. Forget that! Plus, there is a design flaw with the Cadence - the propeller system can't be raised to get through shallow areas which are common around here. Maybe that is why the Cadence company is for sale - design flaws and no distributors equals no sales.

I'm all for the fast pedal boat of any type propulsion. If there are ever any pedal boats made that are FASTER than the Hobie, that are just as stable, that I can throw gear in for a multi-day trip, that can handle open water paddles (3-6 foot seas), and can be sailed, please let me know.

[Busabuck]

The appendage drag on a pedal boat can be significant. The most efficient arrangement I have developed uses a 1/4" spring steel shaft hanging off a right angle gearbox driving the prop. The shaft does not need any other support providing it is pushing but I normally use a tiny strut to allow me to go in reverse. The attached photo shows the shaft unsupported and this works very well.

I calculate losses down to as little as 0.25W and work to eliminate them.

OK - so the problem with the cycle drive shaft is that you need a large spinner on the prop to shroud the gear. This comes at a significant cost in extra drag. There are other more efficient ways to eliminate the chain.

Mitrpak are sponsoring Greg K. in his various boats and I have been working with them on a purpose built drive leg that incorporates two of their boxes.
This shows the product range and an idea of costs:
http://www.mitrpak.com/

I have also attached a photo showing a drive leg I made that uses a small gearbox underwater and one at the top with a chain reduction. This could be engineered into a simpler arrangement but again highlights the need to keep the underwater bits small.

It is no accident that the fastest pedal powered boat used an air propeller.

Could someone here tell me what materials are used in constructing a long narrow hull for a pedal powered boat such as this one? I'm thinking foam blocks, such as those used for home insulation glued together and shaped. Then fiber glass on outside surfaces with plywood on top for mounting seat and drive.
Also where to source the materials.
I know someone on this forum should already know all this, but I'm a rookie who wants a pedal powered boat capable of 10 to 12 knots in a sprint.

[Rnykster]

...The Hobies are well suited to their market but they perform badly against performance craft like surf-skis, racing kayaks and rowing sculls. One advantage of the Hobie is that they require little technique. A person of average fitness can move quite well compared to what they could in a paddled or rowed craft.

Surf-skis and racing kayaks are very unstable boats due to extremely narrow widths and you are right, the Hobie, compared to them, will never perform as well.

Can someone in a surf-ski or racing kayak propel themselves, steer, and take photos at the same time? Can they lay back in their kayak at look at the stars at night? Can they load up the kayak and go on a multi-day trip? Can they sail their kayak? No.

I used to have a narrow racing kayak and was never comfortable taking photos from it. How much faster was it compared to the Hobie? Less than 1 mph. I sold my racing kayak because the extra 1 mile per hour wasn't worth the lack of comfort. The prizes offered in kayak races are no incentive for me to pursue faster and faster speeds.

What was the average speed of Greg in his pedal boat during his 24 hour world record? Just over 6.3 mph. What was my average speed in a recent race with the Hobie? 5.3 mph. What's the difference? 1 mph. Could Greg load up his kayak for a multi-day trip? Could Greg attach a sail to his record performing kayak? I doubt it. It is unbelievable that this recreational Hobie pedal boat is capable of achieving average speeds within 1 mph of record setting pedal boats.

With my Hobie - I have a stable kayak geared for a variety of uses like touring, photography, fishing and sailing, plus it is fast enough to out perform many of the more unstable narrower paddle kayaks. It requires no special gear or techniques, and even an older person like me can perform well in it. A big plus for me is, Hobie stands behind their product and it is available locally.

Yeah, my Hobie might perform 1-2 miles per hour slower than than top of the line high performance pedal boats, but my ride is comfortable. I don't hesitate to take it out into a 3 foot chop and was never comfortable taking my racing kayak out into such conditions. Hobie pedal boats are the way to go.

[portacruise]

You raise some interesting point Rnykster. The Hobie is obviously much better for what YOU like to do in a boat. That is a separate issue than efficiency or speed which can translate to less fatigue and thus greater range, etc. It should be easy to design a comfortable propeller craft that outperforms the Hobie and can do all the things you have listed that you like. I have not seen any indication that a Hobie can maintain 5.3 knots for 24 hours like Greg did.



I am a senior citizen that likes to fish and take pictures at small rivers and creeks in remote locations when I travel by air. Nothing on the market comes close to what I need in stability, low weight, comfort or portability, with 2 hands free (no rudder). So I had to tinker to get a shorter, slower inflatable pontoon craft. Maybe, In a sense, I have a world speed record at 3 knots in that application, since no other craft can even get access to some of these locations.... :-)

Porta

[Rnykster]

Originally Posted by portacruise

It should be easy to design a comfortable propeller craft that outperforms the Hobie and can do all the things you have listed that you like.

The only significant request I have for a pedal boat is that it be stable enough to take photos from and be able to carry enough gear for an overnight trip. If it is so easy to design a pedal boat that out performs the Hobie, where are they?

The Wavewalker claims to be the fastest human powered watercraft in production that almost anyone can cruise 5-6 mph on. (I scoff at this because I consider cruising to be something I can do all day). If almost anyone can cruise at near 6 mph on a Wavewalker, why hasn't it been use to set 24 hour endurance records? It could be that this kayak is better than Hobie, but at 120 pounds, I just don't see myself picking the Wavewalker up and carrying it to the launch sites. The Wavewalker is also as scarce as a dinosaur around here - a legendary species that no one has ever seen.

Anyone can claim to have the best and fastest designed pedal craft, but if you don't produce it and distribute it, the design is worthless. The Pedalos, another pedal craft that is in high demand, is yet another ghost boat.

I challenge anyone who says it is easy to design a pedal boat that performs better than a Hobie to design it, get it produced and distributed. When my local kayak store stocks it, I'll buy it. Meantime, talk is cheap.

[spidennis]

there's three different kinds of people, those that buy off the shelf, those that are willing to build what they need, and those that will modify stuff to suit their needs. Have you seen the Kruger boat with the mirage drive in it used in the watertribe florida everglades challenge? If you're really happy with the hobie mirage drive unit then maybe a route similar to this is for you? Just adapt what is available and make it work.

http://www.watertribe.com/
http://race.fit2paddle.com/C74144504...603/index.html
btw, "pelican" has since moved to a hobie ai ......

Portacruise,
did I somehow miss pics of your craft?
it sounds very interesting, refresh my memory?
thanks,
spidennis

[portacruise]

Originally Posted by Rnykster

The only significant request I have for a pedal boat is that it be stable enough to take photos from and be able to carry enough gear for an overnight trip. If it is so easy to design a pedal boat that out performs the Hobie, where are they?

The Wavewalker claims to be the fastest human powered watercraft in production that almost anyone can cruise 5-6 mph on. (I scoff at this because I consider cruising to be something I can do all day). If almost anyone can cruise at near 6 mph on a Wavewalker, why hasn't it been use to set 24 hour endurance records? It could be that this kayak is better than Hobie, but at 120 pounds, I just don't see myself picking the Wavewalker up and carrying it to the launch sites. The Wavewalker is also as scarce as a dinosaur around here - a legendary species that no one has ever seen.

Anyone can claim to have the best and fastest designed pedal craft, but if you don't produce it and distribute it, the design is worthless. The Pedalos, another pedal craft that is in high demand, is yet another ghost boat.

I challenge anyone who says it is easy to design a pedal boat that performs better than a Hobie to design it, get it produced and distributed. When my local kayak store stocks it, I'll buy it. Meantime, talk is cheap.

CHECK OUT THIS WEBSITE: http://www.prophish.com/ If you want speed and room for gear, the glaskipper has gone to South America from U.S. If you want something lighter than the Hobie or faster (which you didn't mention before), check out the inflatables. Not available at the local convenience store because it doesn't have the huge $ required for slick marketing and hype. NO, I do not own one of these, because they are too heavy and bulky for what I like to do. They will custom design to a certain extent.

I couldn't find anything on the market that came even close to my 35# weight limit so I had to tinker and make something for what I like to do. I wasn't going to give up because I couldn't find it at some corner store. Customizing ideas is a lot about what is communicated on this site, so it has helped me hone my craft to a unique situation.

Your are lucky that you have found something off the rack that fits your needs! Good for you, nothing is wrong with that, ENJOY, and ignore the racing talk as I do, unless it can help me improve something.

Porta

[Rnykster]

Originally Posted by spidennis

there's three different kinds of people, those that buy off the shelf, those that are willing to build what they need, and those that will modify stuff to suit their needs. Have you seen the Kruger boat with the mirage drive in it used in the watertribe florida everglades challenge? If you're really happy with the hobie mirage drive unit then maybe a route similar to this is for you? Just adapt what is available and make it work.

Yes, I've seen the Kruger Boat used in the watertribe challenge. I'm actually quite happy with the performance of my mirage drive unit and see no need to try to tinker for more speed. I'll leave that to the designers and manufacturers. Some say the propeller is best, others say there is less energy loss using the Mirage drive.

Everyone is so hyped up on getting 0.01 more miles per hour that no one is focusing on the need for national, regional and local races with appropriate boat divisions so that an Outback races against other Outbacks, where a Wavewalker races against other Wavewalkers, where a Native races against a similar Native pedal boat, and similar. Plus, there should also be that open category for those who do their own boat modifications in order to get that extra tenth of a mile per hour so they can claim to have the fast boat in the world.

[spidennis]

Originally Posted by Rnykster

When my local kayak store stocks it, I'll buy it. Meantime, talk is cheap.

If I had to wait for my local stores to have anything I'd want I'd just be without. Everything I have to hunt for, build and modify somehow. It would be great if what I wanted was off the shelf locally, but that's just not the part of the world I live in. The world is still evolving and not everything is either been built or in it's time.