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      Abbreviated rules   07/28/2017

      Underdawg did an excellent job of explaining the rules.  Here's the simplified version: Don't insinuate Pedo.  Warning and or timeout for a first offense.  PermaFlick for any subsequent offenses Don't out members.  See above for penalties.  Caveat:  if you have ever used your own real name or personal information here on the forums since, like, ever - it doesn't count and you are fair game. If you see spam posts, report it to the mods.  We do not hang out in every thread 24/7 If you see any of the above, report it to the mods by hitting the Report button in the offending post.   We do not take action for foul language, off-subject content, or abusive behavior unless it escalates to persistent stalking.  There may be times that we might warn someone or flick someone for something particularly egregious.  There is no standard, we will know it when we see it.  If you continually report things that do not fall into rules #1 or 2 above, you may very well get a timeout yourself for annoying the Mods with repeated whining.  Use your best judgement. Warnings, timeouts, suspensions and flicks are arbitrary and capricious.  Deal with it.  Welcome to anarchy.   If you are a newbie, there are unwritten rules to adhere to.  They will be explained to you soon enough.  
Russell Brown

R2AK 2018

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On 1/15/2018 at 1:35 AM, RickW said:

For pedal drives on an 8t catamaran I fitted a combination of Mitrpak boxes to large model aircraft props after observing the buckling issue with a curved shaft.  The eventual fold down drive legs were very effective.  Two people could sustain around 2.5kts. The first year on they gave considerable advantage up the Derwent in light, flukey winds.  In the photo below you can see the pedal drives folded up with the big two bladed prop resting on the seat back.  The first iteration were drop-in drives and there were times when the pedallers could not not slow the prop down to release cleats when they were motor sailing.  The idea of the prop thrusting against the transom then folding up when unloaded was an essential to avoid that condition.

 pretty picture.  

If you want to get into detail on a pedal drive for a specific application it is best to email me:

rickwill@bigpond.net.au

 

Peccadillo_3peaks.png

Wow.  Is that a Chris White Atlantic 46 cat? 

And two folks can move it at 2.5 knots sustained under pedals alone?!  To me at least that is freaking amazing.  Its a big boat that is not super light and has lots of windage.

If you don't mind another question, what type of set-up would you recommend for a small trimaran.  Lots of F27s do this race... as well as similar tris. Being an F27 owner and interested in the race I am starting to try to understand my options...

That is amazing stuff you did for Peccadillo... in my ignorance I would not have thought it possible.

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10 hours ago, RickW said:

Russ

I doubt that a curved shaft would be very useful in your set up.  My choice, without gearboxes, would be two toothed belts with a common middle shaft just below the bridge deck that allows the bottom of the leg to flip up sideways.  You can mount 14T pulleys for a T10 industrial belt inside a 50X50 aluminium tube.  Two shorter belts are no more expensive than a single long belt.  A 310T 16mm belt here costs AUD168 While 156T belt costs AUD56.  I usually use 24mm wide belts on crank pulleys bigger than 32T.  These allow maximum power from most adult males.  For pure endurance use the 16mm wide belts are adequate.  The black Twin-8 in earlier links only has 16mm wide belts and it has done more than 1000km including one MR340.

Bicycles have a constraint that these drive legs do not because the rear wheel is on the centreline requiring the chain to be offset.  Although the bicycle parts are convenient they are quite bulky compared with a belt drive or heavy duty chain.  Also the bicycle chainring overhangs the shaft so shaft flexing causes chain misalignment.  To avoid corrosion issues experienced with chains, I tried the Gates carbon drive belt and found the drag on the centre track was horrible.  A standard T10 belt rides off the pulley if the pulley is mounted on a crank arm spider.  That indicates the drag required on flanges to keep the belt on the pulley.  With a toothed belt the pulley can be supported by a bearing either side; meaning shaft flexing does not cause misalignment.  In fact a toothed belt on a properly supported shaft is more efficient than a typical bicycle chain when they are under load.  

The crank pulley would be say 42T to give you a 3X ratio to a 14T pulley on the bottom of the crank unit then two 14T pulleys inside the bottom part of the leg.  The bottom part would need to be braced so it could be held down against the prop torque as well as a means of lifting the prop. The intermediate shaft needs to be of sufficient diameter to take the bending moment from the thrust although it would be possible to have a fore-aft brace that pivots in line with the centre shaft to eliminate the bending moment on that shaft.

The belts in use on about 10 boats over the last three years are maintenance free.  There is no messy lubrication.  They will operate in water but the belt teeth tend to create a vacuum in the pulley teeth so they get noisy when wet.  It is not particularly difficult to exclude water to a satisfactory level.  Unlike a gearbox or even chain the belts do not deteriorate in water.  The aluminium pulleys get some surface corrosion though. 

Rick

 

Rick, this is a lot of information that you have shared. I have been all over the map in my head and in sketches with this pedal drive thing. That I managed to build a successful one for the last race in a few weeks just before the race now seems kind of unlikely.

Facing sideways was what allowed my last unit to be so simple and efficient, but it really doesn't help much with my new quest for a unit that can be deployed quickly.

Having the leg fold sideways is not very attractive because I have low underwing clearance and the thought of hitting the folded leg with solid water at  high speeds doesn't seem like a good idea

I could see having the leg fold aft using the two separate belt system that you mentioned, but I would need a third belt to joint the two at cockpit floor level. I can picture how all this could work, but is it a good idea? I don't know.

I was attracted to the bent shaft thing because it is only two sprockets, one chain, a universal joint, and a long shaft with a prop at the end of it. It's simple, and it fits the geometry of my boat. I want to ask if you can see a way that it could work. Maybe a stiff carbon shaft for the front half and a flexible shaft aft?

Would you be willing to help me as a client, instead of just giving me free advice? That seems more reasonable to me. That way I may have a chance of having the system work the first time. I can provide a CAD drawing of the geometry of the boat including the proposed pedal pylon, etc.

Russell

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Russell, I have a SeaCycle I'm not using if you'd like to borrow it, but it's in Victoria.

I've organized a tour of the Joint Rescue Coordination Centre Pacific ( JRCC ) here in Victoria for 1000hrs, Friday January 23rd followed by a tour of Marine Communication and Traffic Services ( MCTS ) at noon, also here, in Sidney.

Maximum 10 people. I'll give R2AK entrants booking priority, race applicants next priority, and wanna-be dream racers third.

PM me an E'ddress and we can confirm details. Full names, addresses and date of birth required for security clearance. Unfortunately, we cannot accept any non-Canadian guests at this time, no offence, it's just way more complicated.

First come first serve.

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4 hours ago, Russell Brown said:

 

Would you be willing to help me as a client, instead of just giving me free advice? That seems more reasonable to me. That way I may have a chance of having the system work the first time. I can provide a CAD drawing of the geometry of the boat including the proposed pedal pylon, etc.

Russell

Russ

I do not charge for design work unless it has commercial value.  I usually make some money from the bits and pieces I supply for pedal boats and pedal drive units.  However I only make special parts that are not available off-the-shelf.

The concern I had for the sideways swinging leg was if there was enough cockpit width to park it hard up under the deck.  I doubt a 50mm faired bump hard to the bridge deck would cause much drag.  But there may not be enough width available for leg length required to get the prop submerged.

Depending on the overall length you have available there is the possibility of using a stiff aluminium tube to get down to water level then a shorter length of curved shaft to get the prop perpendicular.  There would need to be a CV joint or universal joint where the tubular shaft connects to the horizontal shaft.  Single universal joints at a relatively high angle are feel jerky to pedal.  The more complex joints cannot take any thrust meaning both shafts need to be supported and aligned.  That becomes complex.  

One of the designs I came up with has a belt box with nominally 5X ratio that has a double universal joint attached to an inclined shaft that is mounted off the belt box. That then connects to a 17-7 stainless curved shaft.  The shaft has a thrust absorbing strut at the prop that allows the prop to be lifted.  As stated before the allowable vertical drop with the 2.4m shaft is 500mm, which limits the diameter of the prop. I have attached a sketch of this arrangement that was designed for a Tornado cat.  The drop can be extended by adding an inclined straight section but that means it is longer.  The double universal for this design that I could find had a price tag of AUD168.

Rick

 

 

Screen Shot 2015-10-29 at 12.11.51 PM.png

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5 hours ago, Wess said:

Wow.  Is that a Chris White Atlantic 46 cat? 

And two folks can move it at 2.5 knots sustained under pedals alone?!  To me at least that is freaking amazing.  Its a big boat that is not super light and has lots of windage.

If you don't mind another question, what type of set-up would you recommend for a small trimaran.  Lots of F27s do this race... as well as similar tris. Being an F27 owner and interested in the race I am starting to try to understand my options...

That is amazing stuff you did for Peccadillo... in my ignorance I would not have thought it possible.

Wess

If you have the room to sit sideways and don't mind facing sideways then belts are the best option in my view.  Gearboxes were the obvious choice for the Chris White cat because the transom steps provided a neat mounting point for for backward facing engines.  Those units were not needed to push against wind.  The 2.5kts was in dead calm.

For side facing a faired tube with a belt inside is a simple way to go.  This is simple top engineer and easy to make from aluminium sections.  Either pivot the leg at deck level to park it or have it drop into a deck  well.  

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Below, a photo of Sidecar’s faired electric drive leg. As Rick says, the belt and pulleys are inside the 50x50mm tube. The drive shaft drops through a slot in the cockpit floor and can be rotated and operated through pretty much 360 degrees.

 Next big challenge is getting it to pedal as well from one position and still rotate as well...... so that I can still use it in either direction, or in the case of a cat or tri, be able to pedal on either side, without back-pedalling.

2C248DC0-A912-4C4C-BF64-6843D48B4482.jpeg

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4 hours ago, RickW said:

Russ

I do not charge for design work unless it has commercial value.  I usually make some money from the bits and pieces I supply for pedal boats and pedal drive units.  However I only make special parts that are not available off-the-shelf.

The concern I had for the sideways swinging leg was if there was enough cockpit width to park it hard up under the deck.  I doubt a 50mm faired bump hard to the bridge deck would cause much drag.  But there may not be enough width available for leg length required to get the prop submerged.

Depending on the overall length you have available there is the possibility of using a stiff aluminium tube to get down to water level then a shorter length of curved shaft to get the prop perpendicular.  There would need to be a CV joint or universal joint where the tubular shaft connects to the horizontal shaft.  Single universal joints at a relatively high angle are feel jerky to pedal.  The more complex joints cannot take any thrust meaning both shafts need to be supported and aligned.  That becomes complex.  

One of the designs I came up with has a belt box with nominally 5X ratio that has a double universal joint attached to an inclined shaft that is mounted off the belt box. That then connects to a 17-7 stainless curved shaft.  The shaft has a thrust absorbing strut at the prop that allows the prop to be lifted.  As stated before the allowable vertical drop with the 2.4m shaft is 500mm, which limits the diameter of the prop. I have attached a sketch of this arrangement that was designed for a Tornado cat.  The drop can be extended by adding an inclined straight section but that means it is longer.  The double universal for this design that I could find had a price tag of AUD168.

Rick

 

 

Screen Shot 2015-10-29 at 12.11.51 PM.png

It takes me a couple of reads to fully understand what you are describing, but I get it. To use a double universal joint, the thrust has to be taken by a thrust bearing on the strut. It appears that you have been down all these roads.

The sideways folding strut really doesn't work because the boat is so narrow. If I used the stiff/flexible shaft drive, I can get the lower sprocket/universal joint down to about 250mm above the waterline (with a fairing in front of it). If the shaft was 3 meters long and half of it was a stiff tube, the stiff part could end about 75 mm below the waterline to put the prop well underwater (but square to the waterline). The universal joint would take about 12 degrees of deflection at this level of immersion according to my drawing. Would this amount of deflection take a double universal joint? All inputs about universal joints welcome!

If I used the stiff/flexible shaft, it could be quite a bit longer than 3 meters to make the angles better and I have 3 potential strut locations along the length for supporting such a long shaft and for installing a thrust bearing if I need to use a double universal joint. I have bought SS universal joints from McMaster-carr that seem good. Expensive yes.

I have learned a lot from you already, Rick. I can send you some $ when we get this all figured out, or I can return the favor in some other way possibly.

I think it's good to keep this discussion public as we don't know much about this stuff over here. Monster trucks and mega yachts are the way here. Pedal drives for boats are for sissies...

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2 hours ago, Russell Brown said:

It takes me a couple of reads to fully understand what you are describing, but I get it. To use a double universal joint, the thrust has to be taken by a thrust bearing on the strut. It appears that you have been down all these roads.

The sideways folding strut really doesn't work because the boat is so narrow. If I used the stiff/flexible shaft drive, I can get the lower sprocket/universal joint down to about 250mm above the waterline (with a fairing in front of it). If the shaft was 3 meters long and half of it was a stiff tube, the stiff part could end about 75 mm below the waterline to put the prop well underwater (but square to the waterline). The universal joint would take about 12 degrees of deflection at this level of immersion according to my drawing. Would this amount of deflection take a double universal joint? All inputs about universal joints welcome!

If I used the stiff/flexible shaft, it could be quite a bit longer than 3 meters to make the angles better and I have 3 potential strut locations along the length for supporting such a long shaft and for installing a thrust bearing if I need to use a double universal joint. I have bought SS universal joints from McMaster-carr that seem good. Expensive yes.

I have learned a lot from you already, Rick. I can send you some $ when we get this all figured out, or I can return the favor in some other way possibly.

I think it's good to keep this discussion public as we don't know much about this stuff over here. Monster trucks and mega yachts are the way here. Pedal drives for boats are for sissies...

OK - it is probably time to do some layouts.  An inclined shaft with a universal joint is possibly a workable option.  If you are starting out only 250 above the waterline then you may get away with a single curved shaft.  I have used my folding prop with submergence less than 250.   There is benefit in having the prop closer to the middle of the boat than right aft or even behind the transoms.  Generally a pedal drive is used in calmer conditions so pitching is not too bad but the closer it is to the longitudinal CoB the better from a ventilation perspective.  With a small cat, that lists with the weight of the pilot, there can even be benefit in having the prop off centre as a prop nearer a hull is less likely to ventilate in a beam sea. Also the centre of resistance is offset from the centreline so the thrust line for neutral helm is offset as well.

I do not know at what angle a single universal joint feels jerky but I have never used one with an angle as low as 12 degrees.  I would usually opt for a double to smooth the torque but a single might feel OK at lower angles. 

I have not looked through the entire thread to see if you mentioned the size of the prop you are using.  My folding prop is only 330 diameter so it requires a submergence of about 260 at the hub centre where I locate it to avoid ventilating in waves; typically only 1m aft of the CoB.  

With regard to sissies, one of my inspirations for pedalling on water was a great uncle, a WW1 veteran, who never got a drivers licence.  He cycled everywhere until he was 92 when his diminishing eyesight limited his ability to cycle in traffic.  With that as a reference, I figure cycling is good for my health and longevity.  There are not many forms of exercise more enjoyable than being in a reclined seat pedalling a boat at a nice pace over water - weather provides variation. People I know who have built pedal boats inevitably lose weight. Being able to hit 10kts under my own power at my age is quite satisfying.  

 

 

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7 hours ago, RickW said:

Being able to hit 10kts under my own power at my age is quite satisfying.

Clearly I have a LOT to learn. 

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My comment about pedal drives being for sissies was a bad attempt at self deprecating humor. It's not a surprise however that the world expert on pedal drives for boats is from the Land Down Under. I guess we have as many cyclists here as anywhere, it's just that we have more monster trucks and mega yachts than anywhere else.

Rick, I'll work on the geometry drawing. I don't do CAD, so need to talk Brandon into helping me. Most of it is there, just need to insert the new pylon geometry.

 

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Holy pedal drives!

I fell asleep part way through this thread (since we don't have a multihull and a pedal drive wouldn't work), even though it was quite interesting reading in terms of learning something new.

And, now, I just realized/remembered (we've never used it) that the Cal 20 of course has an outboard engine well and accompanying opening on the bottom of the hull.  Am brainstorming pedal drives  in my head now (instead of rowing set up)...once we get our registration in, that is - tomorrow!).  Pedalling while facing aft, something could probably be rigged up...

(Maybe as a back up to oars after one gets tired of rowing a 2000 lb monohull! :-) )

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53 minutes ago, Jud - s/v Sputnik said:

Holy pedal drives!

I fell asleep part way through this thread (since we don't have a multihull and a pedal drive wouldn't work), even though it was quite interesting reading in terms of learning something new.

And, now, I just realized/remembered (we've never used it) that the Cal 20 of course has an outboard engine well and accompanying opening on the bottom of the hull.  Am brainstorming pedal drives  in my head now (instead of rowing set up)...once we get our registration in, that is - tomorrow!).  Pedalling while facing aft, something could probably be rigged up...

(Maybe as a back up to oars after one gets tired of rowing a 2000 lb monohull! :-) )

But that is sort of the point that is maybe missed.  I came in here thinking that for sure I would do 2 sweep oars (one on each float) of my F27 which is 3000 lbs BTW and so more weight and windage than what you are talking about. But what I got back was lots of PMs saying go pedal drive its more efficient.  And I see other F27 owners doing that.  So pedals are maybe more efficient even for you monohull.

Not that I have the slightest idea yet row to build rig them but I am listening and reading!!

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2 hours ago, Jud - s/v Sputnik said:

...And, now, I just realized/remembered (we've never used it) that the Cal 20 of course has an outboard engine well and accompanying opening on the bottom of the hull.  Am brainstorming pedal drives  in my head now (instead of rowing set up)...once we get our registration in, that is - tomorrow!).  Pedalling while facing aft, something could probably be rigged up...

Have a look at the (Searunners) Seascape 18 drive setup from the 2016 R2AK , that was an outboard well job from memory.....

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56 minutes ago, Sidecar said:

Have a look at the (Searunners) Seascape 18 drive setup from the 2016 R2AK , that was an outboard well job from memory.....

Great - thanks a lot for the reference.  Will definitely check that out.

(The good thing about oars is that, for this year, a rowing set up will be easy-peasy to set up as compared to a peddle drive.)

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3 hours ago, Russell Brown said:

My comment about pedal drives being for sissies was a bad attempt at self deprecating humor. It's not a surprise however that the world expert on pedal drives for boats is from the Land Down Under. I guess we have as many cyclists here as anywhere, it's just that we have more monster trucks and mega yachts than anywhere else.

Rick, I'll work on the geometry drawing. I don't do CAD, so need to talk Brandon into helping me. Most of it is there, just need to insert the new pylon geometry.

 

I took the sissies comment in the spirit it was intended; with a smile.  Also most of the design work I do for pedal boats is for guys and gals in North America.  The fellow I am working with on commercialisation of a boat lives in Texas.  The fellow that supplies the 17-7 shafts in another Texan.  A fellow in Missouri has made moulds for building the Twin-8 and V16-62 hulls.  The 6.2m hull he made for Greg K weighs just 5.2kg:

I am also privileged to do design work for Matt Johnson who has the biggest engine of anyone I have worked with.  He can still sustain 300W for a couple of hours.  He is planning to just pedal to Alaska this year.  He is reducing the weight of Rouleur right now by eliminating any sailing gear and using lighter materials in some areas.  Pedalling a boat that moves easily is good fun.    I just took your sissies comment as an opening to explain why I started playing with pedal boats 15 years ago and promote what I feel are benefits.

I gather by Brandon that you are referring to Brandon Davis of Turn Point Design.  I had some input on the pedal drive that Brandon Davis set up.  He started out with the idea of a curved shaft but steered away from it after I pointed out the challenges. He also had one of my folding props but decided to go for a bigger diameter prop after playing with JavaProp.  My prop is really suited to easily driven boats although it has been used on a couple of reasonably heavy R2AK boats; both much heavier than Matt's Rouleur.  Brandon has commented on the ease he can move his little cat under pedal power.

I will await some layouts. 

 

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4 minutes ago, Jud - s/v Sputnik said:

Great - thanks a lot for the reference.  Will definitely check that out.

(The good thing about oars is that, for this year, a rowing set up will be easy-peasy to set up as compared to a peddle drive.)

I have just found a video of Searunners: https://r2ak.com/2016-clip-of-the-day/

Day 22, it is an in cockpit drive facing aft but with the driveleg off the stern...  Apologies.

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On 1/11/2018 at 3:37 PM, lasal said:

Here is an off-the-shelf system http://www.h2proped.com/

I've never used it but I'm posting it because it looks adaptable to a variety of boat types and cockpit configurations with the flex drive. At $750.00 for a complete system it seems priced fairly too. I like that the gearing is compact. I can't comment on it's efficiency obviously, but the drive leg looks clean.

Alex W.'s posts are accurate and helpful on bike part specs.  There are many specs to consider if building your own system, and as Alex just pointed out you'll want to stick with a 3/32" pitch chain, chainrings and cogs. Also consider crank length, bolt pattern, BB spindle type and shell, pedal cadence targeted by gearing, etc, etc. I think Kim Bottles did a bunch of work on a pedal system a while back.

I have used the Mirage system and the low end torque does feel strong and I agree that might be a good thing on a relatively heavy sailboat. Installation, however, would be difficult on most sailboats.

Good luck to this year's competitors!

 

p1110301-2_orig.thumb.jpg.e1c625a49f3b926bfbec9a71444dd415.jpg

Team Pear Shaped Racing installed the H20 ProPed pedal drive system on our Multi 23 trimaran. What we discovered was that the stock flexible cable was not able to handle the torque involved in propelling the fully loaded (550 kgs) boat, and would bind up in the metal tube designed to limit flex under power.  The original design sports a 90 degree deflection from the pedal unit to the cable, as it runs aft through the transom of the boat, in the forward-facing pedal position.  We replaced the stock tubing with a straight tube, changed the pedal orientation to athwartship, and tried it again, but still ended up binding the flex cable due to the torque.  As a result, we could not achieve a sustainable pedaling cadence to power the boat at the target 3 knots of boat speed.  We also experimented with different prop pitches, to reduce torque (with considerable input from Brandon, at TurnPoint Design), but that didn't work either.  In the end, we installed Mail Order Bride's rowing stations, and were able to achieve 3-4 knots of boat speed through Active Pass, against 3.5 knots of current on Day 1 (before hitting the log, early the next morning).  Let me add that rowing the Multi 23 was a hate mission due to the large dihedral, which made it extremely difficult to balance the boat so the Canadian and I could maintain consistent rowing cadence.  We canted the rig so that one of us would always be lower / higher than the other, but every time a BC Ferry came by, we were screwed.

Suffice it to say we will be investing significant time and effort to design a workable pedal drive for "Dragon" for 2019.  We have our top Canadian engineers Googling solutions as I type...

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Pelicano, Don't you know how dangerous it is to have engineers work on important things? I'm kidding sort of, but would be interested to know what you are thinking about for a pedal drive. This thread has been pretty educational so far. I wish you were going to make it this year, but understand about getting to know the boat, etc. How many crew are you planning for 2019?

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Hey Rick, thanks for sharing your expertise here.  I notice your early prototypes used flapping foils instead of propellers and guess that they work better at low speeds, partly because of wetted surface area drag?  Anyway, on a cat like Russel has, with a pair of rudders, I wonder if you could flap the rudders for propulsion effectively?  A leg powered variation in the coupling arm between the two could flap them out of phase so wouldn't impact a turning moment.  Thoughts??

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1 hour ago, Kenny Dumas said:

Hey Rick, thanks for sharing your expertise here.  I notice your early prototypes used flapping foils instead of propellers and guess that they work better at low speeds, partly because of wetted surface area drag?  Anyway, on a cat like Russel has, with a pair of rudders, I wonder if you could flap the rudders for propulsion effectively?  A leg powered variation in the coupling arm between the two could flap them out of phase so wouldn't impact a turning moment.  Thoughts??

Kenny

A flapping foil can be made as efficient as a propeller.  Although larger in area than a prop, the flow over it is not much faster than boat speed.  Flow over the tip of prop blades can be a number of times faster than boat speed.  The problem I had with the large single sweeping foil was setting off vertical bouncing of the boat above 9kph that added drag.  The opposed sweep of the Hobie flappers overcome that.  The Hobie flappers are not as efficient as a single high aspect sweeping blade providing the latter is not bouncing the boat.  I used a torque arm to control the blade AoA so the angle of attack did not alter much; meaning the leg load was almost constant.  Also the AoA was constant over the entire blade.  The Hobie flappers rely on rubber flexing to provide the angle of attack.  

Setting up any flapping system requires matching its load to human biomechanics.  That would be the challenge for flapping rudders.  I consider the Hobie flappers awkward compared with spinning a crank.  My most biomechanically efficient pedal system used hanging swing arms to pull wires driving capstans on roller clutches turning a prop shaft.  The aim was to get my CoG as low as possible so I could pedal a narrow hull without using stabilisers:

https://1drv.ms/v/s!Aq1iAj8Yo7jNgm1SJ7euuXess2iX

 

The attached video shows the inventor of the roller clutch drive in his boat.  His is set up like a small outboard whereas I drove a curved shaft.  His turning is very good.

The videos are a decade old now so resolution is not that good but file sizes are smaller.

Warren_HC.wmv

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Thanks Rick, seems like his rudder foils are similar in size to your flapping foils.  We've all sculled sailing dinks with the rudders and it works ok, even with a system totally not designed for that purpose.  Have you considered flapping rudders before?  I could imagine a system where you pedal like the mirage drive and each leg stroke wags the rudders on each rotation.  The Mirage drives use a chain over cam setup I think.  A  chain sprocket on top of each rudder shaft with the chain crossed in between would provide differential rotation on the two shafts while still allowing the tiller to steer.  Seems like it might be simpler than a prop drive with few disadvantages.

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41 minutes ago, Kenny Dumas said:

Thanks Rick, seems like his rudder foils are similar in size to your flapping foils.  We've all sculled sailing dinks with the rudders and it works ok, even with a system totally not designed for that purpose.  Have you considered flapping rudders before?  I could imagine a system where you pedal like the mirage drive and each leg stroke wags the rudders on each rotation.  The Mirage drives use a chain over cam setup I think.  A  chain sprocket on top of each rudder shaft with the chain crossed in between would provide differential rotation on the two shafts while still allowing the tiller to steer.  Seems like it might be simpler than a prop drive with few disadvantages.

Not sure what you are referring to with "his" rudder foils.  Warren is spinning a prop as I am in my boat using roller clutches - see photo of Warren's propulsion leg.  I used a curved shaft to avoid submerging my capstan and roller clutches.

I have seen a wide range of flapping systems.  One example:

I have set up opposing vertical foils to avoid harmonics but the pedal mechanism was horrible.  There have been scale ship propulsion using vertical oscillating foils.  There was a pedal drive for a single foil but you get some idea of the issues here:

https://www.youtube.com/watch?v=3N3wrZN8mRQ

Chains drives in a horizontal plane are a tough ask on a small boat in the marine environment.  Also I doubt you can get much thrust from a rigid blade.  To get some drive from the area you really need to have lateral motion as well.  Things may appear simple until you have to engineer them to operate in a confined space on a platform that rolls about.  A well designed paddlewheel can be as efficient as a prop but put it on a platform that is rolling and pitching and they are a long way behind a prop.

I have actually seen a flapping system that had a steel frame similar in shape to a dolphin back and tail with heavy rubber stretched across the frame.  The trailing edge of the rubber was free to flex.  It was driven in vertical oscillation by a motorcycle engine with its gearbox and mounted like an outboard on the transom of a 14ft tinny.  It could do about 15kts and would even move the boat along a beach, albeit by accident.  A horizontal version of that would work.  I also think a flap on the back of a pair of high aspect rudders  would work but would always favour a prop.   The flapping outboard inspired my dabble into flapping pedal drives.  Once I started doing the calculations to refine the flapping system it became obvious that rotating foils make the most sense for propulsion.

The Hobie flappers are an elegant design but I know they will not make the distance in the MR340 without repairs when pushed hard.  It takes considerable development to ensure a particular system will have adequate durability. Likewise the capstan drive is an elegant and even efficient drive but it is reasonably easy to have wire work off the capstans and turn pulleys.  The reasons I gave up on the capstans was lack of reverse thrust as well as complete inability to remove fouling from the prop.  At the same time I realised I did not need much wetted surface area or added weight with widely spaced stabilisers to achieve static stability on a low drag, slender hull.

IMG_0680.JPG

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By "his rudder foils", I was referring to Russell's rudders on the G32.  I see what you're saying about lateral motion being required.  The long extension of the amas on the G32 would seem to be compatible with some extra arms to achieve lateral motion.  Looks easy, but the devil is always in the details.  I've got some hours pedaling the Mirage drives in the EC300 and am a big believer in "motor sailing", which really benefits from being able to sail higher, punch through waves, tack with no loss etc.  But you need "always accessible" propulsion and dragging around a prop or having to deploy it are problems.  The rudders have to be in the water anyway, so flapping them is pretty attractive.

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1 minute ago, Kenny Dumas said:

  But you need "always accessible" propulsion and dragging around a prop or having to deploy it are problems.  The rudders have to be in the water anyway, so flapping them is pretty attractive.

The blades on my folding prop are 25mm wide, 145mm exposed length (wetted area 0.007sq.m) and fold back to 45 degrees when not providing propulsion.  The blades have less drag than in-line Hobie flappers when coasting, similar static thrust and more efficient once moving.  Plus I can alter the pitch to match the disc loading to the boat.  

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Here's a potential R2AK boat for sale. I don't know much about this particular boat (besides it's historic significance), or how close to race-ready it may be. https://vancouver.craigslist.ca/van/boa/d/gougeon-32-g32-catamaran-for/6472075385.html

The G-32 is a fairly complex boat (2 separate water ballast systems, four kick-up foils, a fairly complex rig, a self righting system, etc). They are also quite tender and need to be sailed like a beach cat, though they are easy to reef and sail fine under-canvassed. They are also very dry, even going upwind in serious conditions and are quite good camp- cruising boats. They take 10 to 15 minutes to set up and break down at the launch ramp. Very different from anything else in most every way. I sure like mine... 

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7 minutes ago, Trevor B said:

 

i saw a G-32 drive into Santa Cruz last week, any idea whose it was?

 

I sold it to Jonah Lepak.

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My G-32 was in pretty rough shape when I got it. Many of them have already had the gelcoat issue dealt with, or in the case of Pocket Rocket, were built without gelcoat. Questions about individual boats should be addressed by Greg Bull, the living G-32 expert. He is a tech supporter at WEST and can be reached by calling WEST System at 866 937 8797.

Most of the complicated systems on my G-32 (such as the water ballast and centerboards) have not been changed and still work perfectly. I'm just finishing a new steering system for my boat, so have a used, but much reinforced and modified steering system to pass along to someone who needs it, along with many other parts, including a complete rig.

One interesting tidbit about the G-32: They came stock with an 8 hp 2-stroke outboard and would go almost 12 knots with that motor.

I don't believe it will fit into a shipping container as it is over 8' wide and most shipping containers are 8' wide at the door.

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7 minutes ago, Russell Brown said:

 

I don't believe it will fit into a shipping container as it is over 8' wide and most shipping containers are 8' wide at the door.

Maybe sidewise in a high-rise container?

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4 hours ago, Russell Brown said:

My G-32 was in pretty rough shape when I got it. Many of them have already had the gelcoat issue dealt with, or in the case of Pocket Rocket, were built without gelcoat. 

Hi Russell- 

Pocket Rocket was built with gelcoat and has the expected "issues."  Greene Marine filled in a bunch of divots when they were replacing the crazed ports, and the next summer we had a bunch more to do.  I think northern New England winters exacerbate the gelcoat popping issue the same way they accelerate our plethora of potholes: multiple hard freeze/thaw cycles  How have other folk dealt with gelcoat aside from your incredibly intensive radical removal project?

-Mitch

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Thank you ref the shipping container question. I have closely followed Russell Brown's restoration in the past and I have a understanding of some of the boats issues.

I have thoughts of buying a G32 then touring North America with it for six months. Its an interesting camp cruiser.

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11 minutes ago, nacrajon said:

Thank you ref the shipping container question. I have closely followed Russell Brown's restoration in the past and I have a understanding of some of the boats issues.

I have thoughts of buying a G32 then touring North America with it for six months. Its an interesting camp cruiser.

You could skip a lot of the boring bits with a tow vehicle, that makes it really accessible and interesting.

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On 1/27/2018 at 2:45 AM, nacrajon said:

Will a G32 fit into a 40ft shipping container?

I have shipped a Mini Transat which is 9'8" wide in a 40' High Cube container, you need to build an angled cradle but totally doable. 

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Nacrajohn,  Get the G32, you will have a blast.  Aside from the gel coat I had no problems with her.  I you want to take a lot more effort, Tom Roland in Ojai was selling a NACRA 36 which can be set up with a cuddy cabin.  Roy Seaman, had one and it was scary fast.  Happy hunting.

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A NACRA 36 is not camp cruising. There are three in NQLD, an original, a short rig tourist ride with 5 traps and the full carbon NACRA 36 ' Malice'. I have raced against Malice and she is a beast.

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Nacrajon, Tom Roland, built a cool pod that went between the hulls for a boat called "Joker" That went to the east coast.  It came back to him and he sold it to Roy Seaman, in Malibu.  He camper cruised it for years.  The speeds it attained kinda stretched the definition of cruising.  They used to play country music off watch to decompress from the blasting topsides.  Until I got my G32, It was the only boat I truly wanted.  Check it out.

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For the frontrunners - how much paddeling has there been? Ok you need to get out from harbor - but then if you have a fast sailer - is there much to gain on using energy on rowing/padelling? 

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In 2016 we ended up pedalling / motor (pedal) sailing for about 16 hours out of our 5 day race.  Our goal was to never let boat speed drop bellow 4 knots.

We Also used the pedal drive to keep in a wind hole in a tight chanel as a gale went over us on our last night before Ketchikan.  Anchoring was not an option and thus it was great to have a strong pedal drive to be able to jog in place before first light and we needed to make the crossing of Dixon Entrance.

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Racing in the area patchy winds are very often an issue. You might have 5 kt of wind, moving decently, then there'll be a dead calm patch where you can just sit, and sit, and sit, until finally the next wind line moves close enough and you start moving again. Being able to just pedal through that hole, which may well not be more than a few hundred meters, could save a ton of time. 

Back in 2015 Elsie Piddock rowed a bunch the first night, putting something like 15 miles on the rest of the becalmed fleet drifting out in the Strait of Georgia, and that lead was enough to get them the wind first and keep them ahead of the really rough stuff, for ultimately something like a 300 mile lead over 2nd place?

 

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     We had a NACRA 36 at Sailboats South in New Orleans ages ago. Bought it from Texas and it had been 'rode hard and put away wet' as they say in Texas. Nothing major but lots of road rash and small dings and worn way keel laps. Kept me out of trouble during the winter patching things up but come spring we got into a lot of trouble with that boat. Bikinis tended to fall right off when that beast got up to speed! Not sure if we ever named the boat but 'RODE HARD & PUT AWAY WET' would have been a good candidate for a appropriate name.

     Biggest problem was that the compression on the mast ball/dolphin striker kept twisting the main beam in its sockets and straps. Those thin gauge mounting SS mounting strips might be OK on a 18' cat but were letting the mast ball rotated fwd and I can't believe we never lost that rig. We tended to take out too many wild New Orleans ladies and a pod would have been known as the 'Stabbin Cabin'. Our Stiletto hosted even crazier cruises. Good thing there were no GoPro cams in that day and age! There were some photos that I think made the Stilleto newsletter that I would love to have scanned if anyone has those old pubs. 

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Rules state that you can  use human power but not an engine.  Rules say nothing about storing human power. Can you for example produce electrical energy by pedalling and storing it in a battery only to use when needed via an electric motor?

To me this is not an 'engine'  which uses some external fuel.

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12 minutes ago, Omer said:

Rules state that you can  use human power but not an engine.  Rules say nothing about storing human power. Can you for example produce electrical energy by pedalling and storing it in a battery only to use when needed via an electric motor?

To me this is not an 'engine'  which uses some external fuel.

Copied from the rules:

 

  • Every team must have a vessel without a motor. No motors onboard, at all, even if they’re not hooked up, disabled, etc. This includes motors and engines of any fuel type and that includes fossil fuel powered generators. Human and wind power only for propulsion. Solar, wind and human are ok for charging things —and no, not for charging a battery that powers propulsion of any kind. Bilge pumps are ok, unless it’s really big and pointed aft (see Rule 8)

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My new pedal drive design has been all over the map, but I think we are getting close to a decision on which way to go. I'll post some drawings as soon as we have them.

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On 1/25/2018 at 8:04 PM, Russell Brown said:

Here's a potential R2AK boat for sale. I don't know much about this particular boat (besides it's historic significance), or how close to race-ready it may be. https://vancouver.craigslist.ca/van/boa/d/gougeon-32-g32-catamaran-for/6472075385.html

The G-32 is a fairly complex boat (2 separate water ballast systems, four kick-up foils, a fairly complex rig, a self righting system, etc). They are also quite tender and need to be sailed like a beach cat, though they are easy to reef and sail fine under-canvassed. They are also very dry, even going upwind in serious conditions and are quite good camp- cruising boats. They take 10 to 15 minutes to set up and break down at the launch ramp. Very different from anything else in most every way. I sure like mine... 

I wish that had been available a year ago, before I bought my boat!

 

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The rowlock setup on the foot rowing boat is very interesting.  Hanging the oar from a short post with the string tied so the oar self feathers is brilliant.

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7 hours ago, Russell Brown said:

My new pedal drive design has been all over the map, but I think we are getting close to a decision on which way to go. I'll post some drawings as soon as we have them.

Dang, does this mean we're not going to Oz to fetch your Newick?

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18 hours ago, W9GFO said:

Copied from the rules:

 

  • Every team must have a vessel without a motor. No motors onboard, at all, even if they’re not hooked up, disabled, etc. This includes motors and engines of any fuel type and that includes fossil fuel powered generators. Human and wind power only for propulsion. Solar, wind and human are ok for charging things —and no, not for charging a battery that powers propulsion of any kind. Bilge pumps are ok, unless it’s really big and pointed aft (see Rule 8)

So, could you have an efficient wind turbine geared to a prop, reducing healing moments? Just a drunken thought... Ummm.

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1 hour ago, Varan said:

So, could you have an efficient wind turbine geared to a prop, reducing healing moments? Just a drunken thought... Ummm.

Or geared to a peddled paddle wheel...

I, for one,  like Duckhorn Merlot (‘14) powered thought....:wub:

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On 2/12/2018 at 2:43 AM, W9GFO said:

Copied from the rules:

  • Every team must have a vessel without a motor. No motors onboard, at all, even if they’re not hooked up, disabled, etc. This includes motors and engines of any fuel type and that includes fossil fuel powered generators. Human and wind power only for propulsion. Solar, wind and human are ok for charging things —and no, not for charging a battery that powers propulsion of any kind. Bilge pumps are ok, unless it’s really big and pointed aft (see Rule 8)

That doesn't rule out flywheels...  Let's try a 20 lb ring, 26" in diameter spinning at 20,000 rpm = 2,170,563 Joules = 2,057 BTUs.

I don't know how that translates to minutes of pedaling?

Four 5:1 gear ratios in series with a 60 rpm input would be 37,500 RPM... 7.6 M Joules

http://www.botlanta.org/converters/dale-calc/flywheel.html
http://www.calculatoredge.com/mech/flywheel.htm

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That is about 600 watt hours, which is about 3 hours of pedaling at 200 watts. 

I think this is clearly outside of the spirit of the rules.  The goal is clearly to ban energy conservation that can be released into motive power except through humans. 

I look forward to seeing Russell Brown’s plans!  

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38 minutes ago, Alex W said:

That is about 600 watt hours, which is about 3 hours of pedaling at 200 watts.

Thank you.  So one Joule is 0.000277778 watt hours...

38 minutes ago, Alex W said:

I think this is clearly outside of the spirit of the rules.

I don't see it that way but I don't make the rules.

Just to explore the concept a little more, let's say we want 1/2 hour of energy storage, or 100 watt hours... so we need a flywheel that stores 360000 Joules.

That could be three 5:1 gear ratios in series with a 60 rpm input = 7,500 RPM with a 20 lb ring at 28.5 inches diameter.

Or four 5:1 gear ratios in series with a 60 rpm input = 37,500 RPM with a 5 lb ring at 11.5 inches diameter?

Would be a pity if rules prohibited exploring this idea further.  I guess the issue would be that as the flywheel slows down, you need to increase the drive gear ratio...

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16 minutes ago, ProaSailor said:

Thank you.  So one Joule is 0.000277778 watt hours...

I don't see it that way but I don't make the rules.

Just to explore the concept a little more, let's say we want 1/2 hour of energy storage, or 100 watt hours... so we need a flywheel that stores 360000 Joules.

That could be three 5:1 gear ratios in series with a 60 rpm input = 7,500 RPM with a 20 lb ring at 28.5 inches diameter.

Or four 5:1 gear ratios in series with a 60 rpm input = 37,500 RPM with a 5 lb ring at 11.5 inches diameter?

Would be a pity if rules prohibited exploring this idea further.  I guess the issue would be that as the flywheel slows down, you need to increase the drive gear ratio...

Don't let the rules stop you. First, this is a 'Gear Anarchy' thread idea. Second, are you just going to bolt your mythical 37,500 rpm flywheel into the cockpit? I'm sure you have a mechanical PTO all thought out too. If you take this to its own thread, I'll check it out, but not here.

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Rick, recumbent spinning is great for power, but not for torque- torque being very hard on the knees (Ask any long term 'bent rider about the difficulties of climbing).   Is there a bright line as far as torque and knee longevity?  What kind of torque at the pedals does a low speed longer span blade require?    

Pedal length, sprocket sizes, front hub height etc all go into this, but I've never looked onto the technical end of it, mainly augmenting my recumbents with E power to find comfort/speed going up hill, and not having any symptoms afterwards.  My sense of it was I was always overEpowered.  Using off the shelf friction equipment and all, which was limiting as far as power choices....

(edit:  FWIW, I've been riding recumbents since 1982, and getting enough gear reduction (like in a 3*9 setup) to climb comfortably usually means walking is faster:lol:)    

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1 hour ago, Amati said:

Rick, recumbent spinning is great for power, but not for torque

If the power is there, then you can make the torque via gearing. Seems to me that recumbent spinning is okay for power, but being able to stand on the pedals is better for power (and torque).

 

A couple of common misconceptions that are passed around as wisdom;

It's not the HP that matters but the torque.

It's the current that kills you, not the voltage.

In both examples the former cannot exist without the latter, but without the former, the latter is useless.

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 I too have some experience riding recumbents and would add that Amati's connection between torque and knee stress may be an issue for those who don't have many miles ridden in the recumbent position but the larger issue is muscle groups. Traditional bikes use the quad muscles and recumbents use the glutes. Unless you have years of riding in the recumbent position, your glutes will not be up to the job of spinning and climbing in the recumbent position. The development of these recumbent pedal drive systems for R2AK would be better served if the persons pedaling them started training in the recumbent position now, so as not to suffer from expecting too much from an unused muscle group!

This pic is from when we used to race at the Portland Speedway.

tt42.jpg

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7 hours ago, ProaSailor said:

That doesn't rule out flywheels... 

 

 

They don't specifically rule out energy storage devices but they do say you can't charge a battery to use for propulsion. I'm confident that Rule 8 will determine that you also cannot "charge" a flywheel.

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1 hour ago, olsurfer said:

 I too have some experience riding recumbents and would add that Amati's connection between torque and knee stress may be an issue for those who don't have many miles ridden in the recumbent position but the larger issue is muscle groups. Traditional bikes use the quad muscles and recumbents use the glutes. Unless you have years of riding in the recumbent position, your glutes will not be up to the job of spinning and climbing in the recumbent position. The development of these recumbent pedal drive systems for R2AK would be better served if the persons pedaling them started training in the recumbent position now, so as not to suffer from expecting too much from an unused muscle group!

This pic is from when we used to race at the Portland Speedway.

tt42.jpg

Very cool! My Rans came with fairing, which downhill is downright frightening. I Should have put it this way- I used to be able to leg press (sitting) more than my weight, which is much harder to do on a regular bike- the temptation, if you can produce that kind of pressure, is to use it on a ‘bent, and that kind of overuse injury can be severe.  Granted, gearing can ameliorate that, but around seawater, what doesn’t rust?  A sealed internal multiple speed hub with a Kevlar belt?  It does help to start with lighter pressure and work to more pressure, especially if you’re jumping on the pedals cold after you’ve been sitting & sailing.  Or maybe that hasn’t been actual experience?

 

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1 hour ago, W9GFO said:

They don't specifically rule out energy storage devices but they do say you can't charge a battery to use for propulsion. I'm confident that Rule 8 will determine that you also cannot "charge" a flywheel.

I don't see that in black and white.  The rules are very clear about motors but a flywheel is not a motor.  There is a case to be made for flywheels "smoothing" the two peaks per revolution from pedals, even if they don't store any significant power.  Developing a flywheel system to drive a boat more than a few seconds has many technical obstacles and may not be practical so the point may be moot anyway.  And there is a valid argument that any form of stored energy, be it charging a battery or spinning a flywheel, might give unfair advantage to teams with the most money.  But that's already the case, isn't it?  The high tech expensive boats win.  Some form of stored human energy could ultimately be more practical and widely applicable for non-race use than elaborate sweep oar systems that are bolted on.

I only bring it up (again) because there has been no news coming from any competitors on this subject for quite awhile.

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Full race participants include a Melges 32, Hurley 17, Bayliner 18, Hurley 26, CNC 25, Hotfoot 27, Moore 24, sc 27, Morecamby Bay Prawner, Inter 20, Tornado, Miracle 20, Rowcruiser, Triraid and an F28.

Back again are Oaracle[2nd date], the G32 with 3 crew, Roger Mann, Matt Take me to the Volcano...https://r2ak.com/2018-full-race-participants/

Proving Ground leg one features SA'er in the Cal 20, go Judd... https://r2ak.com/2018-stage-one-participants/

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24 minutes ago, Norse Horse said:

Full race participants include a Melges 32, Hurley 17, Bayliner 18, Hurley 26, CNC 25, Hotfoot 27, Moore 24, sc 27, Morecamby Bay Prawner, Inter 20, Tornado, Miracle 20, Rowcruiser, Triraid and an F28.

Back again are Oaracle[2nd date], the G32 with 3 crew, Roger Mann, Matt Take me to the Volcano...https://r2ak.com/2018-full-race-participants/

Proving Ground leg one features SA'er in the Cal 20, go Judd... https://r2ak.com/2018-stage-one-participants/

The TriRaid is mine. Busy with "sea" trials on the Columbus river around Portland. https://www.facebook.com/TeamACER2AK2018/

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3 hours ago, ProaSailor said:

I don't see that in black and white.  The rules are very clear about motors but a flywheel is not a motor. 

That is the purpose of Rule 8 - to cover those things that are not in black and white. No, a flywheel is not a motor, it is an energy storage device. Using a flywheel to smooth out power pulses is very different than using one to store energy so that it can move your vessel while your legs take a break. Personally, I wouldn't care but I don't believe the judges would approve it. 

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4 minutes ago, W9GFO said:

That is the purpose of Rule 8 - to cover those things that are not in black and white. No, a flywheel is not a motor, it is an energy storage device. Using a flywheel to smooth out power pulses is very different than using one to store energy so that it can move your vessel while your legs take a break. Personally, I wouldn't care but I don't believe the judges would approve it. 

The judges would shit all over it and anybody that tried to use it, in my humble opinion. They don't like people doing fuckery with the spirit of the rules. 

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8 minutes ago, W9GFO said:

That is the purpose of Rule 8

Rule 8?  I see only four rules: https://r2ak.com/official-rules/

Oh, buried in the Race Packet: https://r2ak.com/wp-content/uploads/2017/12/Race-packet-2018.docx.pdf

Quote

Rule 8: If we decide it’s necessary to consult a lawyer to figure out if you are disqualified or not, you are automatically disqualified. Play by the rules and live up to the spirit of the race. If you get cute and push the boundaries we’ll bring down the hammer.

Sheesh!

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1 hour ago, Ishmael said:

The judges would shit all over it and anybody that tried to use it, in my humble opinion. They don't like people doing fuckery with the spirit of the rules. 

Nor will the other participants tolerate such fuckery. We do not need lawyers in this race.

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11 hours ago, W9GFO said:

Using a flywheel to smooth out power pulses is very different than using one to store energy so that it can move your vessel while your legs take a break.

Only in degree, not in principle.

9 hours ago, dsackman said:

Nor will the other participants tolerate such fuckery. We do not need lawyers in this race.

"fuckery"?  I wasn't suggesting being sneaky about it.  It's still human powered.  A flywheel is only a buffer for pedal input.  So is a battery charged solely from pedaling.  The spirit of "no motor" could be safeguarded by prohibiting pre-charging before the start of the race.  The idea isn't likely to affect race results at all, is it?

Quote

Man is not permitted without censure to follow his own thoughts in the search of truth, when they lead him ever so little out of the common road.
 - John Locke, Born: 1632, Died: 1704

 

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23 minutes ago, ProaSailor said:

Only in degree, not in principle.

"fuckery"?  I wasn't suggesting being sneaky about it.  It's still human powered.  A flywheel is only a buffer for pedal input.  So is a battery charged solely from pedaling.  The spirit of "no motor" could be safeguarded by prohibiting pre-charging before the start of the race.  The idea isn't likely to affect race results at all, is it?

 

If it wouldn't affect race results then why bother? The spirit of the rules and the ethos of the race are clear. If you don't like them, set up your own race.

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Sure it could affect race results. Given a large buffer you could have multiple crew members pedal nearly full time. When conditions are light you would have 1kw or more power on tap vs the 400w that you get from two cyclists today.  That could make a significant difference in boat speed through the light stuff.

With lithium batteries getting cheaper and cheaper that buffer could cover hours of motoring per day. 

Using a flywheel as a buffer is harder but still illegal. 

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15 minutes ago, IStream said:

If it wouldn't affect race results then why bother? The spirit of the rules and the ethos of the race are clear. If you don't like them, set up your own race.

Pardon me for thinking.  If you don't like that, set up your own forum.

9 minutes ago, Alex W said:

Sure it could affect race results. Given a large buffer you could have multiple crew members pedal nearly full time. When conditions are light you would have 1kw or more power on tap vs the 400w that you get from two cyclists today.  That could make a significant difference in boat speed through the light stuff.

With lithium batteries getting cheaper and cheaper that buffer could cover hours of motoring per day. 

Using a flywheel as a buffer is harder but still illegal. 

Well, 1) the rules could limit the size of the buffer and 2) "that buffer could cover hours of motoring per day" only if someone pedals for even more hours to charge it.  I can see some convenience value in buffering for even a few minutes of relief from pedaling.

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My guess is s that the R2AK organisers aren’t too interested in advancing human/non fossil fuel powered boat technology other than as a by product. 

For them it is all about getting people off their arses and away from sitting in from of the TV or hanging around on Forums and doing something real and challenging. And as cheaply and simply as possible, without creating another millionaires arms race. We have plenty of those already.....

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1 hour ago, ProaSailor said:

Pardon me for thinking.  If you don't like that, set up your own forum.

Well, 1) the rules could limit the size of the buffer and 2) "that buffer could cover hours of motoring per day" only if someone pedals for even more hours to charge it.  I can see some convenience value in buffering for even a few minutes of relief from pedaling.

Feel free to think. So will I. You proposed what I think is a violation of the spirit of the race and I shared my thoughts on that.

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