Russell Brown

R2AK 2018

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1 hour ago, Russell Brown said:

Seems that there are more entrants than the website shows. My friend Larry Olsen just entered in an Olson 30 (team Deam Catchers). There's going to be lots of us old guys trying to make it to Ketchikan. It would be good to see some people that I know on the course.

We'd be happy to motor by and throw beer.

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8 hours ago, Ishmael said:

We'd be happy to motor by and throw beer.

Wait, is that a thing in this race?  Can a specific brew be requested?  Do you take the empties?  Could scotch be arranged LOL?

Bummed to hear that its sounding like Team Ziska is not making it. :(  Yea, I am a multihull kinda guy but I still love old school and Ziska is that.

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The pedestal is the big part. The big pulley is where the cranks (pedals) attach. The lower pulley is offset to starboard to give heel clearance and to offset the leg (the second attachment) far enough that it has room to swing up laterally. Both the leg and the pedestal have pulleys and belts inside. Four shafts and eight bearings (not shown), four pulleys, a long drive shaft connecting the pedestal and leg, an idler pulley, etc, etc...           The leg rotates (kicks up) laterally on the 2 1/8" carbon tube shown in the drawings and photo.

I have made some mistakes already, but it should be operating and I should have photos in a couple of weeks.

DSC_2417.jpg

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The drawings worked and make sense to me.  It looks like a good setup (maybe more complicated than you originally thought, but much more flexible) and I look forward to seeing it all put together.

I get using a belt for the lower run, but why for the upper (which seems to be well enclosed and has the more complicated path)?  I think a chain would work there and be more efficient and cheaper.

The lower leg is pretty small and will be wet, so a belt makes sense since chains don't like salt water or making very small radius bends.

One cool feature with this is that you could easily sub in an electric motor in the future and use the same final drive leg and prop.

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I have no experience with belts, but they have some advantages. Chain is a lot easier to make the right length. The idler pulley in the pedestal was a mistake. I should have made the geometry of the pedestal to allow for a straight path from the upper to lower pulley. The leg will be sealed and will hopefully stay dry inside. I like the electric idea, but I also really like outboard motors, especially when there's a long way to go.

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22 minutes ago, Alex W said:

The drawings worked and make sense to me.  It looks like a good setup (maybe more complicated than you originally thought, but much more flexible) and I look forward to seeing it all put together.

I get using a belt for the lower run, but why for the upper (which seems to be well enclosed and has the more complicated path)?  I think a chain would work there and be more efficient and cheaper.

The lower leg is pretty small and will be wet, so a belt makes sense since chains don't like salt water or making very small radius bends.

One cool feature with this is that you could easily sub in an electric motor in the future and use the same final drive leg and prop.

Ditto on the drawings. My  question has to do with the fastening of the pedestal to the deck. It seems like the CF flanges and fasteners are small, but it's hard to tell scale in the photos. Will it tolerate long-term cyclic loading? Someone falling onto it at an angle? 

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Yeah, you can't beat petroleum for energy density and it would be a shame to load down the G32 with batteries to get any real range.  It would only really be helpful for tight marinas where sailing might not be as practical.

 

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11 hours ago, IStream said:

Ditto on the drawings. My  question has to do with the fastening of the pedestal to the deck. It seems like the CF flanges and fasteners are small, but it's hard to tell scale in the photos. Will it tolerate long-term cyclic loading? Someone falling onto it at an angle? 

The pedestal is supported fore & aft by an aft facing strut. The photo shows an unfinished bunch of hardware on top of an unfinished horizontal plate that holds all the hardware. The strut bolts to the aft crossarm. 

The hardware on top of the pedestal is for the main and screecher/spinnaker sheets. I got used to sheets being always within reach and the G-32 wasn't that way at all. The main sheet comes from the end of the boom, which is the only place to sheet it because of the around-the-boom reefing and furling. The sheet will still come from the end of the boom, but will run through the lead block and cleat to the cam cleats. The screecher/spinnaker sheet will go to the winch. Both sheets will now be in easy reach of the driver. The tiller has to pass between the sheet and the strut, which will be interesting, but I think it will be easier than what I had.

Gybing this boat with the spinnaker or screecher is a handful. There's the mainsheet & traveller, the running backstays, bowsprit from one side to the other, spinnaker sheet, mast rotation, and water ballast. Keeps me on my toes and it's fun.

 

DSC_2456.jpg

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Russell ,for sheeting you could crate a carbon claw with skate wheel bearings that could fit mid boom.  I remember using one in the mid 60s when all the new boats had roller reefing and the sails sometimes didn't set properly.  If the wheels were large enough the point loads would not tear the sails.  I always used the traveler to depower because it was faster acting and easier to reset alone.  Good luck on R2AK

 

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I got a box of propellers in the mail and sliced the hell out of my finger getting one out of the package. I picked out one that I know will work (the shorter one) but got a couple of others to try. At $16 to $20 each it's pretty cheap to experiment.

The shorter on is 16x16. On my old pedal drive I was a bit lugged down with that prop. The new drive will have a bit less RPM at the prop, so the 16x16 could work.

I also got an 18 x 10 and an 18x12. they have much less pitch, but so much more chord width. I think I'll have enough immersion to use a bigger prop if one of them works.

I'm way behind on everything. Our business has been flat out, so working on the boat has hard to find time for. If I make it, it will be just like last year, everything last-minute. 

DSC_2481.jpg

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I'm surprised you didn't go for the adjustable pitch hub with an assortment of blades.

Very economical, very good quality and infinitely adjustable for sea-trialing.

Also, easy to adjust for "motor" sailing in different wind conditions.

Good luck!

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1 hour ago, Russell Brown said:

I got a box of propellers in the mail and sliced the hell out of my finger getting one out of the package. I picked out one that I know will work (the shorter one) but got a couple of others to try. At $16 to $20 each it's pretty cheap to experiment.

The shorter on is 16x16. On my old pedal drive I was a bit lugged down with that prop. The new drive will have a bit less RPM at the prop, so the 16x16 could work.

I also got an 18 x 10 and an 18x12. they have much less pitch, but so much more chord width. I think I'll have enough immersion to use a bigger prop if one of them works...... 

You can always cut the tips off the longer propeller blades. That way you get extra blade area for a smaller diameter prop?

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Oh, you're not familiar, that would explain why you didn't go for them then.

It might take me a while to find, it was before I abandon prop propulsion.

They were from the R/C world if you want to look...

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No joy Russell, but you can probably find them with some perseverance.

I thought it was on RCGroups forum but I checked my history there... must have been another forum.

German as I recall, there were two manufacturers that stood out for variety, quality and price.

Good luck.

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6 hours ago, BarfBag said:

No joy Russell, but you can probably find them with some perseverance.

I thought it was on RCGroups forum but I checked my history there... must have been another forum.

German as I recall, there were two manufacturers that stood out for variety, quality and price.

Good luck.

Google search: "adjustable pitch hub with an assortment of blades R/C German"

http://www.ramoser.de/home_e/varioprop_e/body_product_information.html

TopRcModel 22" 4-Blade Variable Pitch Carbon Fiber Propeller
https://www.gator-rc.com/toprcmodel-22-4-blade-variable-pitch-carbon-fiber-propeller

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Wow, That's quite a piece of gear! For me though, changing the prop is probably easier than changing the pitch and the complexity of the variable pitch is worrisome.

By separating the crank pedestal and drive leg, I get an easy to deploy drive system, but I added a heap of complexity. There's 2 belts, 5 pulleys, 10 bearings, 8 bearing retainers, 6 shafts, and lots of other bits. Bolting on the propeller is about the only relatively easy part of the system. 

There's no telling if my pedal drive will work right, but if it does it will be thanks to to Rick W and my machinist friend, Paul Z. 

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Yah, that wasn't it. The price I found was much better and more selection.

Doesn't matter, as it doesn't suit your fancy anyway Russell.

Not complex at all, easier in fact.

One screw adjusted both blades at the same time, with precision, through an infinite number of AoA's.

Easier than changing a prop and you don't have to remove it to make an adjustment so you can't drop it as you might with the two props involved in a change.

 

 

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Besides their use for experimental pitch adjustment (a static setting), the real value of variable pitch props for airplanes is when pitch can be controlled in use, acting as a form of "gearing", even to the extent of throwing the plane into reverse!

 

 

 

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ProaSaler,

I think you are confusing variable pitch with adjustable pitch.

Variable pitch would be doable but not sure the complexity would warrant the reliability risk and cost for an event like R2AK.

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I am not confused at all.  Just leaping to the idea of being able to adjust pitch while pedaling.  Worth a try, eh?  If someone hasn't already?

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Proa, that flying video was amazing.

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The pilot was pumping about 15 hp (electric) through that hub and blades. Should be no problem for human power.

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10 minutes ago, Jim Caldwell said:

The pilot was pumping about 15 hp (electric) through that hub and blades. Should be no problem for human power.

I had no idea that plane was electric!!  Here is the full description:

Quote

HORIZON Airmet 2015 Genderkingen / Germany
Markus Rummer

Delro Raven
Spw. / Wingspan: 3.1 m
Motor: Hacker A200 modifiziert / modified
Gewicht / Weight: 20kg

2x Emcotec Stromversorgung (1x für Verstellprop 1x für Flieger)

Lipo: 12s 2P 10.000mAh (für 4 min Flug / for 4 min. flight)

Extras:
Custom 700 Size Spin Helicopter Blades
Controllable Pitch Propeller With Vector
6 Jahre Entwicklung / 6 years of development

https://hackermotorusa.com/shop/hacker-brushless-motors/outrunners/archive-superceded-motors/a200-8/
https://hackermotorusa.com/shop/brushless-motors/outrunners/q100-9500-watt-brushless-motors/q100-9m-7100-watt-brushless-motor/

Quote

Q100-9M: 7,100 watt brushless motor

$1,099.00

The Q100 is the highest evolution of outrunner motor design for competition RC applications — optimized for maximum power and a lightweight package. Every Q100 is made by hand with strict quality standards at Hacker’s workshop outside Munich, Germany.

Power range   max. 7,500W (15 sec.)
Idle current at 8.4V   1.86A
Resistance   0.00106 Ohm
Kv   110
Weight   1,830g / 4 lbs. 
Diameter   113 mm
Length (Backmount – Prop)   95.5 mm
Pole   28
recommend ESC   MasterSpin 220 OPTO
recommend Timing   25-30°
Shaft   10mm center boss, 6 bolt prop hub

 

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On 2/16/2018 at 12:48 AM, Russell Brown said:

I'm not exactly tough, but I managed to do the race by making sure that I got plenty of rest. I anchored every night and pushed as hard as I could when there was wind. It didn't seem to matter when I finished, only that I didn't wreck the boat by being stupid. You don't need balls, just some seamanship, navigation, and sailing skills 

I didn't make a lot of miles pedaling. Human power was more to get to the wind or get around a corner. That being said, there was wind last year. This year the race starts a bit later, so who knows...

I'm not a huge fan of rowing big boats, but I have gimpy wrists that don't like rowing. I do like pedal power, but pedal power for boats is a developing art...

 

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A solo team called me tonight and asked if i could bring a boat to the r2ak18, the only slightly ready boat is my Reynolds 33x16, it would be easier/less expensive if there were three on the team.  My quess, is to win it would cost up to $10k, second place is closer to $4k, anyone with multihull experience want to join?

Monday we have to pay the balance.

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PS, that's 10HP not 15HP, but compared to the 1/7HP average human output, you're right, plenty strong enough for 1/2HP human bursts.

But the momentary torque loads can be significant so not all that overbuilt in reality.

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17 hours ago, Rasputin22 said:

Go for it with the Reynolds! Next year for the Antrim. How is the Gumbo?

Balance paid, r2akteamgoldenoldies is now r2akteamLexiesgift.

 

getPart-4.jpg

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Congrats, bring me the Maine to baby sit while you do the R2AK. You know that this weekend is the New Orleans Jazz Fest. I have friends coming over for that madness and can get a ride and then we can leave Monday!

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12 minutes ago, Rasputin22 said:

Congrats, bring me the Maine to baby sit while you do the R2AK. You know that this weekend is the New Orleans Jazz Fest. I have friends coming over for that madness and can get a ride and then we can leave Monday!

You kill me, call. 

Stephen 775 219 8679

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1 hour ago, SeaGul said:

That will be interesting - a "right" looking 34ft proa up against many fast tris.

https://r2ak.com/2018-teams-full-race/team-fly-baby-fly/

Wow.  That looks pretty cool.  Don't think I've seen this one before?  What's the full story?  Designer/builder?

Fly-Baby-Fly_R2AK.jpg

P.S.  Comment from RB on a different thread:

56 minutes ago, Russell Brown said:

That boat isn't racing in the R2AK. It hasn't ever really sailed, I think. From what I heard, the guy who was going to race the proa is now racing on a Reynolds 33.

 

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On 1/5/2018 at 6:32 PM, Norse Horse said:

Ho-Lee-Cow...

Roger Mann is rowing the 2018 r2ak in a Liteboat....

20 teams already.

Race packet hints at expecting more interaction with VTS

Leg One racers must be qualified to do the entire course to be accepted.

A bank is willing to pony up to sponsor a team.

https://r2ak.com/2018-teams-full-race/team-gas-monkey/

https://www.facebook.com/racetoalaska/

Hey - Question for you.  I PM’d you as well, but thought this might reach you better.

We’re now not 100% sure we can make it.  Our local marina with launch ramp/small yard now tells us it’s forbidden to do any work whatsoever in their yard - we were planning to haul out and quickly clean/paint bottom this weekend - and they just now pulled the rug out from under us. Fuckers.  Oh well.

Where do you haul out your YM20? (You’re in Squamish, right?)  Any suggestions?  We’re totally stuck now b/c our trailer isn’t “road worthy” (old and rusty), but is quite sufficient for on-island haul out/relaunch, but which we’re now told we can’t do...so aren’t sure where we can take a Cal 20 out of water...am curious what you do/where you go for your boat.  Race Rocks only lists down to 24’ on their site for lift prices.

Feels like the death of cheap sailboat adventure to me, our friendly little island marina forbidding haul outs (while yard is full of commercial water taxi boats doing...bottom work/prop and shaft work).

Thanks for any advice.

 

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1 hour ago, Jud - s/v Sputnik said:

Hey - Question for you.  I PM’d you as well, but thought this might reach you better.

We’re now not 100% sure we can make it.  Our local marina with launch ramp/small yard now tells us it’s forbidden to do any work whatsoever in their yard - we were planning to haul out and quickly clean/paint bottom this weekend - and they just now pulled the rug out from under us. Fuckers.  Oh well.

Where do you haul out your YM20? (You’re in Squamish, right?)  Any suggestions?  We’re totally stuck now b/c our trailer isn’t “road worthy” (old and rusty), but is quite sufficient for on-island haul out/relaunch, but which we’re now told we can’t do...so aren’t sure where we can take a Cal 20 out of water...am curious what you do/where you go for your boat.  Race Rocks only lists down to 24’ on their site for lift prices.

Feels like the death of cheap sailboat adventure to me, our friendly little island marina forbidding haul outs (while yard is full of commercial water taxi boats doing...bottom work/prop and shaft work).

Thanks for any advice.

 

Have you tried contacting the Race Boss.  He might have some useful advice.  It would be worth sending an email at least.

I hope you get something sorted out.  The yard seems to be run by a bunch of pricks.

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11 hours ago, Tunnel Rat said:

Have you tried contacting the Race Boss.  He might have some useful advice.  It would be worth sending an email at least.

I hope you get something sorted out.  The yard seems to be run by a bunch of pricks.

Thanks - I’ve got a plan B and C, even D (most expensive, and doesn’t allow for painting: pay for diver to clean bottom).

It’s not so much the yard people are pricks (owner is a woman, too :-) ), it’s that its atmosphere has totally changed over the years.  Used to be more friendly/community-oriented.  Recently, however, climbing real estate values here have started to wreak their changes on what was once a somewhat sleepy island community.  The marina/yard is busy doing many other things and doesn’t want to deal with haul out issues.  Oh well, on to Plan B and C.  (If sailing/adventuring teaches us nothing else, it’s having back up plans...)

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Made it - the 40 year old creaking, rusting trailer (with extra steel struts bolted on for insurance...) held together, much to our surprise and contrary to our big fears  (front left tire went completely flat, however, leaf spring bolts scraping on the cement down the trailer ramp...), successfully launching the 52 year old boat (with new bottom and topsides paint).  (Did I mention we’re on a skinny, tied-together shoestring budget?  Bigger adventure that way!).  A friend lent a truck, the tide timing was absolutely perfect, and two other knowledgeable friends were available to trailer and help unstep/step mast.  Everything came together without too much drama.

Next steps:  perfecting our rowing system, and getting to Port Townsend.  Fingers crossed!

Team Calico

https://m.facebook.com/mightycalico

D0FE97E1-9331-439C-A620-2B84853222EF.jpeg

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

Made it - the 40 year old creaking, rusting trailer (with extra steel struts bolted on for insurance...) held together (front left tire went completely flat, however, leaf spring bolts scraping on the cement down the trailer ramp...), successfully launching the 52 year old boat (with new bottom and topsides paint).  (Did I mention we’re on a skinny, tied-together shoestring budget?  Bigger adventure that way!).  A friend lent a truck, the tide timing was absolutely perfect, and two other knowledgeable friends were available to trailer and help unstep/step mast.  Everything came together without too much drama.

Next steps:  perfecting our rowing system, and getting to Port Townsend.  Fingers crossed!

Team Calico

https://m.facebook.com/mightycalico

D0FE97E1-9331-439C-A620-2B84853222EF.jpeg

A bootstripe and a cove stripe would really make a difference there. A little bit of gold leaf really makes a yacht sparkle.

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15 minutes ago, Ishmael said:

A bootstripe and a cove stripe would really make a difference there. A little bit of gold leaf really makes a yacht sparkle.

You, sir, are a man of high taste - and obviously more time than me :-). It was an absolute race over the past 48 hours to just get topsides and bottom paint on.  (The bottom was *completely* fouled, I’m embarrassed to say.)

(The boat would really sparkle with more attention, but simply no time right now - it’s all about functionality now!)

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

You, sir, are a man of high taste - and obviously more time than me :-). It was an absolute race over the past 48 hours to just get topsides and bottom paint on.  (The bottom was *completely* fouled, I’m embarrassed to say.)

(The boat would really sparkle with more attention, but simply no time right now - it’s all about functionality now!)

I'm just yanking your chain. As long as you don't spray-paint the name on the stern it's all good.

c85ab99a59b3abec83490547fad6d5e1.jpg

 

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Even the shop that boat was built in is cool. I'd love a ride on that one.

I'll have a pedal drive report in a day or two. It works!

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11 hours ago, Ishmael said:

I'm just yanking your chain. As long as you don't spray-paint the name on the stern it's all good.

c85ab99a59b3abec83490547fad6d5e1.jpg

I will admit, 8 years ago when we got the old Cal 20, that I hastily and temporarily taped a name on the transom with electrical tape - supposed to be only for the dockside renaming party.  It stayed on, forgotten, as we sailed the boat hard, and upgraded running rigging, instead of beautifying it.  Eventually, I got around to removing the vestiges ofmyhe tape which, of course lifted up the ancient paint underneath.

Spray paint would be, let’s face it, a bit of an abomination - unless you’re “Pestilence”!  (I admire Holdfast’s pluck, but not necessarily their aesthetic :-)

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I just watched your film.

Good on ya.

Regards, and fair winds.

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

Made it - the 40 year old creaking, rusting trailer (with extra steel struts bolted on for insurance...) held together, much to our surprise and contrary to our big fears  (front left tire went completely flat, however, leaf spring bolts scraping on the cement down the trailer ramp...), successfully launching the 52 year old boat (with new bottom and topsides paint).  (Did I mention we’re on a skinny, tied-together shoestring budget?  Bigger adventure that way!).  A friend lent a truck, the tide timing was absolutely perfect, and two other knowledgeable friends were available to trailer and help unstep/step mast.  Everything came together without too much drama.

Next steps:  perfecting our rowing system, and getting to Port Townsend.  Fingers crossed!

Team Calico

https://m.facebook.com/mightycalico

D0FE97E1-9331-439C-A620-2B84853222EF.jpeg

Glad you sorted out your antifouling. I pm'ed you re squamish facilities there are none...just a boat launch and a tide grid you cant paint at. 

My rowing setup on thr Young 6m was 10ft oars with the locks 12in back from the thwart and a fixed seat. I had locks at 10 in as well but used the 12in position all the time. The oars did not sweep together at full stroke so it was a bit of a bastardized setup. The locks were mounted on the cockpit combing so the oars would sweep past the gunwales. I could make 2 knots on calm water. 

With a 15-20 knot headwind it was tough rowing into victorias inner harbour. Some tesams like superfriends had real problems rowing and sculling from the stern woth a sweep. One team in 2017 tried swimming and towing the boat with the painter but were told no by the harbour patrol.

Rowing out of port townsend harbor in heafwinds was tough for most in 2016.

I would suggest 12ft oars and trying a counterweight like NRS sells, and a paddleboard paddle for an auxillary.

Fair winds

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You could kedge pretty effectively with 500 meters of 200 lb test braided dyneema fishing line, $20, 1 lb. and take along a inflatable SUP or kayak to set an anchor way the fuck out front.  Inflatable would provide some safety margin as well.

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Three weeks from tomorrow morning, R2AK starts from Port Townsend June 14, 2018, 0500: https://r2ak.com/

I've collected some related links to charts and weather info here: http://wingojo.com/r2ak/

Including this update for 2018 tide changes at Seymour Narrows:

R2AK History at Seymour Narrows

In 2015, Team Elsie Piddock made it to Seymour Narrows in just under 30 hours (~148 miles via the Trincomali Channel and Porlier Pass).
In 2016, Team MAD Dog got though Seymour Narrows only ~24(?) hours after the start!

2018 Currents at Seymour Narrows

Seymour Narrows Current Predictions, June 19, 2018, tides.mobilegeographics.com/locations/5757.html
50.1333° N, 125.3500° W (navionics chart app)

SeymourNarrows_2018Jun19_5757.png

To avoid an opposing flood current, the first three opportunities to get past this "gate" appear to be:

  • Monday morning at 9:21 AM (when the ebb begins) until 3:30 PM (when the flood begins)
  • Monday night at 10:16 PM (~34 hours after the start) until Tuesday morning at 4:51 AM (when the flood begins)
  • Tuesday morning at 10:29 AM (~46 hours after the start) until Tuesday afternoon at 4:31 PM (when the flood begins)
Ebb flows north (favorable, in green), Flood flows south (adverse, in red):

2018-06-18 Mon 9:21 AM PDT -0.0 knots Slack, Ebb Begins
2018-06-18 Mon 12:35 PM PDT -9.8 knots Max Ebb
2018-06-18 Mon 3:30 PM PDT 0.0 knots Slack, Flood Begins
2018-06-18 Mon 6:51 PM PDT 12.1 knots Max Flood
2018-06-18 Mon 9:34 PM PDT Sunset
2018-06-18 Mon 10:16 PM PDT -0.0 knots Slack, Ebb Begins
2018-06-19 Tue 1:30 AM PDT -11.3 knots Max Ebb
2018-06-19 Tue 4:51 AM PDT 0.0 knots Slack, Flood Begins
2018-06-19 Tue 5:11 AM PDT Sunrise
2018-06-19 Tue 7:34 AM PDT 7.5 knots Max Flood
2018-06-19 Tue 10:29 AM PDT -0.0 knots Slack, Ebb Begins
2018-06-19 Tue 1:37 PM PDT -8.7 knots Max Ebb
2018-06-19 Tue 4:31 PM PDT 0.0 knots Slack, Flood Begins
2018-06-19 Tue 7:49 PM PDT 10.6 knots Max Flood
2018-06-19 Tue 9:34 PM PDT Sunset
2018-06-19 Tue 11:07 PM PDT -0.0 knots Slack, Ebb Begins
2018-06-20 Wed 2:26 AM PDT -10.8 knots Max Ebb
2018-06-20 Wed 3:52 AM PDT First Quarter
2018-06-20 Wed 5:11 AM PDT Sunrise
2018-06-20 Wed 5:49 AM PDT 0.0 knots Slack, Flood Begins
2018-06-20 Wed 8:40 AM PDT 7.8 knots Max Flood
2018-06-20 Wed 11:43 AM PDT -0.0 knots Slack, Ebb Begins
2018-06-20 Wed 2:45 PM PDT -7.8 knots Max Ebb
2018-06-20 Wed 5:39 PM PDT 0.0 knots Slack, Flood Begins
2018-06-20 Wed 8:51 PM PDT 9.2 knots Max Flood
2018-06-20 Wed 9:34 PM PDT Sunset
2018-06-21 Thu 12:00 AM PDT -0.0 knots Slack, Ebb Begins
2018-06-21 Thu 3:25 AM PDT -10.6 knots Max Ebb
2018-06-21 Thu 5:11 AM PDT Sunrise
2018-06-21 Thu 6:46 AM PDT 0.0 knots Slack, Flood Begins
2018-06-21 Thu 9:46 AM PDT 8.6 knots Max Flood
2018-06-21 Thu 12:59 PM PDT -0.0 knots Slack, Ebb Begins
2018-06-21 Thu 3:57 PM PDT -7.5 knots Max Ebb
2018-06-21 Thu 6:51 PM PDT 0.0 knots Slack, Flood Begins
2018-06-21 Thu 9:35 PM PDT Sunset
2018-06-21 Thu 9:54 PM PDT 8.2 knots Max Flood
2018-06-22 Fri 12:55 AM PDT -0.0 knots Slack, Ebb Begins
2018-06-22 Fri 4:24 AM PDT -10.6 knots Max Ebb
2018-06-22 Fri 5:11 AM PDT Sunrise
2018-06-22 Fri 7:42 AM PDT 0.0 knots Slack, Flood Begins
2018-06-22 Fri 10:48 AM PDT 9.6 knots Max Flood
2018-06-22 Fri 2:10 PM PDT -0.0 knots Slack, Ebb Begins
2018-06-22 Fri 5:09 PM PDT -7.8 knots Max Ebb
2018-06-22 Fri 8:04 PM PDT 0.0 knots Slack, Flood Begins
2018-06-22 Fri 9:35 PM PDT Sunset
2018-06-22 Fri 10:56 PM PDT 7.6 knots Max Flood
2018-06-23 Sat 1:49 AM PDT -0.0 knots Slack, Ebb Begins

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Great stuff! I'll print that.

The Navionics program I'm using for navigation shows tidal currents, but shows basically nothing North of Vancouver island. The long channels inside of the outer islands had 1-2 knots of current and there doesn't seem to be a way of predicting when and what direction it will flow. I have not looked to see what is available for tides (highs and lows) between Vancouver island and Ketchikan, but I should do that soon.

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On 5/22/2018 at 4:14 PM, Kenny Dumas said:

You could kedge pretty effectively with 500 meters of 200 lb test braided dyneema fishing line, $20, 1 lb. and take along a inflatable SUP or kayak to set an anchor way the fuck out front.  Inflatable would provide some safety margin as well.

Would this be considered legal? I LOVE the idea!

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He's a short video of the new pedal drive in action. I started a blog post with some details and I'll post a link to that soon.

 

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Nice. You'll never go back to gas again...

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It is pleasing to see a basic design nicely executed.  Even greater buzz to see smiling faces on people enjoying a pedal on the water.

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4 hours ago, Russell Brown said:

He's a short video of the new pedal drive in action. I started a blog post with some details and I'll post a link to that soon.

 

Very nice. But i am puzzled by the choice of propellers. To me they are built for air not for water. I have never seen  a slim  two bladed  outboard engine propeller . What is the theory behind them?

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Isnt just good modern carbon oars simpler and better system for moving a multihull - specially to get out to the first start - if it wind or current against you need good power in short time. A reasonable 30ft tri can have 4 oars with 4 rowers  and develop a lot power.

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2 hours ago, Omer said:

........What is the theory behind them?

The theory of propellers and turbines is the same for water as air just the fluid is a little different.   Air propellers are primarily designed for high efficiency.  Water propellers are commonly designed for strength and cavitation sometimes plays a dominant role; but not all.  For example this Siemens water turbine pictured on the link:

http://www.siemens.co.uk/en/news_press/index/news_archive/seagen-achieves-5gw-tidal-power-generation-milestone.htm

uses a high aspect blades that are consistent with high efficiency.  It would not be regarded as practical for a high aspect prop similar to this to push a moderately sized vessel. 

 

When designing for human power there is not much power to play with so the objective is to not waste it on spinning a tiny prop with low aspect blades at high rpm.

 

My best prop, pictured, achieves an efficiency of 84% on one of my easily driven hulls.  It is strong enough to achieve more than 10kts.  The blades have 20mm chord and are 2mm thick.  Overall diameter is 360mm. This compares with about 50% for a typical small diameter 3-blade outboard prop pushing a sailing boat. 

IMG_20170811_085010.jpg

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On 5/22/2018 at 10:42 AM, Norse Horse said:

Glad you sorted out your antifouling. I pm'ed you re squamish facilities there are none...just a boat launch and a tide grid you cant paint at. 

My rowing setup on thr Young 6m was 10ft oars with the locks 12in back from the thwart and a fixed seat. I had locks at 10 in as well but used the 12in position all the time. The oars did not sweep together at full stroke so it was a bit of a bastardized setup. The locks were mounted on the cockpit combing so the oars would sweep past the gunwales. I could make 2 knots on calm water. 

With a 15-20 knot headwind it was tough rowing into victorias inner harbour. Some tesams like superfriends had real problems rowing and sculling from the stern woth a sweep. One team in 2017 tried swimming and towing the boat with the painter but were told no by the harbour patrol.

Rowing out of port townsend harbor in heafwinds was tough for most in 2016.

I would suggest 12ft oars and trying a counterweight like NRS sells, and a paddleboard paddle for an auxillary.

Fair winds

Thanks for the info/suggestions - BTW why did you have a fixed rowing seat?  I’d have thought a sliding seat would be much more efficient (if a bit more complicated to build).

To anyone - if building a sliding seat, how would you estimate how long the seat needs to slide?  (On my boat, the seat would need to slide on “tracks” -I’d use aluminum angle - but I’m wondering how to estimate needed length.  Haven’t done a “test stroke” yet - perhaps that’ll give me an idea how long the seat tracks need to be?)

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1 hour ago, SeaGul said:

Isnt just good modern carbon oars simpler and better system for moving a multihull - specially to get out to the first start - if it wind or current against you need good power in short time. A reasonable 30ft tri can have 4 oars with 4 rowers  and develop a lot power.

The R2AK race has the option to motor/sail.  The limitation is that the motive power is human.  The ability to readily deploy and stow the propulsionsion system is a huge benefit in flukey conditions.  As the ability for a single person to motor (pedal) while controlling sheets and rudder, which is not possible if the hands are holding oars.  I guess you could use you teeth for the sheet and maybe feet for the tiller but it would require some adaption.

You get a good indication of the benefit of props and pedals on an 8t catamaran in the first 40 seconds of this video:

This was the second year they used these pedal drives.  Like the R2AK, human power is permitted in the Three Peaks Race around Tasmania.  The first year with these drives Peccadillo won the race and gained a huge advantage by motor sailing up the Derwent River in flukey conditions.  Any time sailing speed was under 4kts they could pedal to hold apparent wind.  It makes a huge difference on a multihull to keep momentum up in light winds.  

 

The pedal props on Pecadillo are 700mm diameter.  Think how many blades it would take to replicate the same swept area; keeping in mind that a paddle spends about 50% of the time out of the water on the recovery stroke.

 

Russell's video above, towards the end, also tells a tale when he is single handedly motoring out of a tight marina.  He has hands free to steer the boat while providing the motive force to move it with the pedals.  He can stop almost instantly if needed and reverse effortlessly.  In a tight location like this it is not practical to row; maybe paddling is possible but with not much authority.  Then there is the need to stow the oars.  Over long duration, pedalling is considerably easier on the body than rowing.  Oars become cumbersome if the boat is joggling about in a left over slop.  

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Rick,

What are "flukey" sea conditions? 

I don't see the advantage in the first 40 seconds of the video...

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RickW, as i remember from my Fluid Mechanics lectures some 20 years ago, the maximum power recoverable from the wind or any other fluid (coefficient of power) is limited by BETZ coefficient which is 59.3 % of available kinetic energy. This is the max. theoretical energy before all mechanical losses and electrical losses due to energy conversion.   All wind turbines strive to get as close to this as possible  only with high aspect 3 blade configurations. Also if i remember correctly 3 blade configurations are the only way to achieve max. efficiency and in reality it does not exceed 45-49 %

Therefore, if the fluid mechanics theory has not changed in the past 20 years, i am intigued about your 84 % efficiency measure achieved by  two blades. Are we talking about different criteria when quoting efficiency?

I believe recovering energy from a flowing fluid is just the reverse of putting enegy from an outside source to a static fluid and the theory remains the same. 

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Looks great Russell!

 

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All I can say is that anyone who thinks oars would work should try rowing a boat this big. Pedaling at 2 or 2 1/2 knots is pretty effortless, rowing at that speed would be a misery. The cool thing about oars is the simplicity and reliability. Not yet sure how reliable my pedal drive will be, but simple it is not.

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On 4/17/2018 at 7:49 AM, Wess said:

Wait, is that a thing in this race?  Can a specific brew be requested?  Do you take the empties?  Could scotch be arranged LOL?

Bummed to hear that its sounding like Team Ziska is not making it. :(  Yea, I am a multihull kinda guy but I still love old school and Ziska is that.

Good god, we were sailing the Mug Race one year, eight exhausting hours of cold, hard wind and rain. In this my wife turns to me with a smile, reaches into her foulies, and pulls out a flask of scotch. I will never forget that smile, or that moment.

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I'd be slightly skeptical of an 84% efficient prop (in my world 55% and you're doing good). But for real low power where you are not restricted by RPM or diameter and you have really long thin blades maybe 84% is achievable.

The only way you'd happily row a bigger boat is with small area oars (with lots of slippage past the blades).

Two blade props are more efficient than three. One blade is better still in a perfect world (where one assumes a cow is a perfect sphere with no friction...) - but issues of balance come up! In the real world you're often constrained by cost, diameter and material properties (wind turbines) so 3 is a good compromise.

 

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

 

Thanks for the info/suggestions - BTW why did you have a fixed rowing seat?  I’d have thought a sliding seat would be much more efficient (if a bit more complicated to build).

To anyone - if building a sliding seat, how would you estimate how long the seat needs to slide?  (On my boat, the seat would need to slide on “tracks” -I’d use aluminum angle - but I’m wondering how to estimate needed length.  Haven’t done a “test stroke” yet - perhaps that’ll give me an idea how long the seat tracks need to be?)

I have a sliding seat setup now, the tracks are about 30in long. I also have some 12ft sculling oars. I am still not able to row with the oar handles crossing at the end of the stroke like you see Colin Angus do in his Rowcruiser. Rowing a 20ft 1500lb boat loaded with gear, water and battery is more akin to rowing an aluminum cartopper loaded with your fishing buddies or rowing  your wide inflatable tender loaded, with the undersized Chinese oars it comes with.

The lighter the sliding seat, the better. I have an old Nanaimo RC setup.

Have at look at the r2ak videos of Colin, Nate Rooks and Matheiu and other long distance rowers to see how much blade they use in the water with each stroke.

 

 

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7 hours ago, Omer said:

RickW, as i remember from my Fluid Mechanics lectures some 20 years ago, the maximum power recoverable from the wind or any other fluid (coefficient of power) is limited by BETZ coefficient which is 59.3 % of available kinetic energy. This is the max. theoretical energy before all mechanical losses and electrical losses due to energy conversion.   All wind turbines strive to get as close to this as possible  only with high aspect 3 blade configurations. Also if i remember correctly 3 blade configurations are the only way to achieve max. efficiency and in reality it does not exceed 45-49 %

Therefore, if the fluid mechanics theory has not changed in the past 20 years, i am intigued about your 84 % efficiency measure achieved by  two blades. Are we talking about different criteria when quoting efficiency?

I believe recovering energy from a flowing fluid is just the reverse of putting enegy from an outside source to a static fluid and the theory remains the same. 

The Betz limit relates solely to a turbine and is the maximum fraction of the power in a given area of a stream flow  that can be converted to mechanical energy using a turbine.  It is unrelated to efficiency as defined, being work out to work in.  

 

Marine propeller efficiency can exceed 90%.  This link has the Wageningen B-series marine prop data.  

Publication_No_237.pdf?sequence=1&isAllo

You will see as you progress through these charts that the 2-blade high aspect blades (low Ae/Ao), starting at a value of 0.3 have an efficiency in the high 80s.  The efficiency falls as the blade area ratio increases meaning the blade aspect ratio is reducing.  These values are for Reynolds number of 2E6, which is much higher than my small props under pedal power so I have to contend with much higher values of viscous drag relative to other loss factors.  I have a blade area ratio of around 0.07 and very low disc loading, which does compensate for the much lower Reynolds number.

 

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12 hours ago, BarfBag said:

Rick,

I don't see the advantage in the first 40 seconds of the video...

You need to read the the words that show during the video and realise that the photographs taken from the 8t catamaran initially show two boats level with oars out in the water and then a later photo taken from the cat with those two boats falling behind and oars still deployed.  So oars and pedal thruster means winds are flukey at best - maybe no wind:

https://www.google.com/search?client=safari&rls=en&ei=mH0HW92IOYzC0gT_z5fgBA&q=flukey+wind+sailing+conditions&oq=flukey+wind+sailing+conditions&gs_l=psy-ab.3...24433.26145.0.26785.5.5.0.0.0.0.269.883.0j1j3.4.0....0...1c.1.64.psy-ab..1.0.0....0.ksNs0y_mXvQ

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Rick, the prop I ended up being happy with is the one on the left on my post from April 28 (this page). I'm pedaling about 65 rpm's at cruising speed x 4.9 at the prop (about 320 rpm) and the prop is 16" x 16" (406 mm x 406 mm). This is the only model airplane prop I can find with more than 11" of pitch. I'm about to order some spares, unless you have other ideas. If there was something available with a bit more chord length, I'd sure like to try it.

I'll post some more info about the new unit tomorrow.

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21 minutes ago, Russell Brown said:

Rick, the prop I ended up being happy with is the one on the left on my post from April 28 (this page). I'm pedaling about 65 rpm's at cruising speed x 4.9 at the prop (about 320 rpm) and the prop is 16" x 16" (406 mm x 406 mm). This is the only model airplane prop I can find with more than 11" of pitch. I'm about to order some spares, unless you have other ideas. If there was something available with a bit more chord length, I'd sure like to try it.

I'll post some more info about the new unit tomorrow.

Russell

I have attached a screen image from Javaprop of roughly where you are operating based on the 3.3kts I saw and the figures you have given.  This indicates the 16X16 is reasonably well matched.  It takes a lot of detail to get above 80% for a prop in you application.  If you used a 20X16 prop you will gain about 3% in efficiency but that translates to 1% in speed.

I encourage untrained recumbent riders to learn to spin as this reduces the risk of muscle fatigue as you are working muscles aerobically rather than pushing them into anaerobic state and building lactic acid.    A trained cyclist will like to spin in the range 80 to 90rpm.  For untrained that feels energetic as it works lungs harder than legs.  It pays to spend at least 1 hour pedalling to determine if your legs are loaded nicely.

Motor sailing is a different condition and you may like a higher pitch to keep assisting in the 4 to 6knot range without throwing legs out of joint.  I have not motor sailed much but could not keep up above 11knots and the pedals pulled away from my feet - no cleats because I did not want to be uncleating if I rolled.   With the big cat we had the prop lift once it was no longer thrusting to avoid the condition of feet spinning at a huge rate when the boat accelerated. It is impossible to brake a 760mm prop with legs once it is acting as a turbine. The pedal props on Peccadillo were 30x20.

 

You can certainly get higher pitch the 16".  It is rare to get P/D greater than 1 in model aircraft props.  So if you want to try bigger pitch then you need to go bigger diameter as well then reduce the diameter if that causes issues.

https://www.rcworld.com.au/props/apc-prop-20x18-f-1-gt-race.h1982873637_ScreenShot2018-05-25at1_29_32pm.png.d9d6ec4bb6159798f0a13b5ab2925b96.png

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Russell -

That is some really good craftsmanship and an interesting design.

In looking at the video ie appears the prop is in front of the "skeg" (what do you call it?). Just wondering if there would be a bit less drag if it was a aft. Cessna used to have a twin engine plane with one engine in front and the other aft and it was quite efficient, and there have been other aircraft with pusher props. Just wondering (assuming what I'm seeing is a prop in front instead of aft). 

Any thoughts?

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1 hour ago, Russell Brown said:

.....I'm pedaling about 65 rpm's at cruising speed x 4.9 at the prop (about 320 rpm) and the prop is 16" x 16" (406 mm x 406 mm). This is the only model airplane prop I can find with more than 11" of pitch. I'm about to order some spares, unless you have other ideas. If there was something available with a bit more chord length, I'd sure like to try it.....

Russell

https://www.modelflight.com.au/apc-22-x-12-wide-electric-propellor.html

They also have a 27x12 in stock, not listed.... cut it down in diameter to suit, and you get more durable tips.

I also have an APC 18x14 spare.

Most props in Australia come from USA, so I am surprised that you can’t find anything with more grunt...

Rob

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There is also a difference between a prop that achieves max efficiency in flat water/no wind, and one that works when you are trying to leave/enter the harbour with a headwind and a bit of chop. Designing right on the tip of the peak efficiency curve is not a great idea. Better to be on the left hand side of the prop chart so you have a bit in reserve when conditions require a bit more push but speed is lower than assumed.

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3 hours ago, Zonker said:

I'd be slightly skeptical of an 84% efficient prop (in my world 55% and you're doing good). But for real low power where you are not restricted by RPM or diameter and you have really long thin blades maybe 84% is achievable.



 

The Wageningen data I posted link to at #570 should remove any slight skepticism you may have.

I am able to do absolute measurements of efficiency but I mostly use measured data for comparison purposes:

https://1drv.ms/v/s!Aq1iAj8Yo7jNgkEyyWL7EiGrTnJC

https://1drv.ms/b/s!Aq1iAj8Yo7jNgkNl2VwqqpmzbOFk

This was a test of the design for the carbon prop using printed blades with a light sheathing of carbon.  The blade flex limited maximum motor input power to 133W so the comparisons were all done under 9kph.  

The comparison curves include the motor losses.  So they are not ideal comparisons because the prop pitches are different and the motor was working more efficiently at the lower rpm with the printed prop.  The 6374 SK3 motor I was using is rated at 2000W on the voltage I was using so the sub 100W was way down at the bottom of its performance.  

The full carbon prop was 3 to 4% more efficient than my standard folding prop when I tested it under human power.  

Doing absolute efficiency tests requires a lot of measurements and having ideal conditions for full scale testing is rare.

Under race conditions my folding prop has proven the best because it is almost indestructible and readily sheds weed but it is a bit small for anything over 200kg.   The carbon prop is just for sprinting where weed might ruin a run but easy enough for another run with weed removed.

 

 

 

 

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Blade flex is another reason why I think it is a good idea to get oversized diameter aeromodeller props and cut them down to suit your max preferred diameter....

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Out of interest do you prefer to pedal  sitting to port or is pedalling backwards from the starboard seat  ok?

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1 hour ago, overlay said:

Out of interest do you prefer to pedal  sitting to port or is pedalling backwards from the starboard seat  ok?

If you are asking me, I don’t pedal, but I would like to as well, I have an electric motor drive leg which uses model aeroplane propellers.

On Russell’s boat, he can only “push” pedal and drive forward from one side, presumably he has a preferred side and set it up for that..... I would imagine that pedalling backwards on the other side would be less comfortable and much less efficient.

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39 minutes ago, Russell Brown said:

A short blog post about the pedal drive: https://gougeon32.blogspot.com

I'll know a lot more about this unit soon. Wish it was simple, but it sure seems to work well.

Russell

What type of bearings did you end up choosing?

There is a reasonable amount of weight added but the pedestal is a large part of that and it serves a double purpose.  

O-ring shaft seals work reasonably well.  Mitrpak gearboxes are fitted with O-rings for shaft seals.   A little bit of water on the belt just makes a fraction more noise. I have found belts and the aluminium pulleys highly durable in the salt air environment.  

This drive has been much simpler to execute than a drive with curved shaft.

I have added a photo sent from someone you may see in the R2AK.  He is using a curved shaft with twin belt drive to get the required gear ratio.  I recommended a universal joint to get the shaft down angle but he has twisted the first belt.  I am not a fan of any twist in a belt but the relatively small twist on a relatively narrow belt is tolerable.  The unit was as much a test of precision metal cutting as creating a pedal drive.  

 

Rick

Screen Shot 2018-05-26 at 1.41.42 pm.png

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Sweet drive unit Russell.  And thanks for all the great fab tips you share in your blog.  Craftmanship is a gift.

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I’m building an outrigger canoe, Va’a motu, with an ama to port and aluminum bars suspended about 42” off centerline, so about 30” space between gunnel and the bar. 

Could a simple crankset with a large diameter bearing between the pedals belt drive a lower bearing with universal joint to a spring steel shaft?

i think bracing points would be the aluminum bar, the gunnel, and the forward crossbeam to the left of the cycle system.

My goal is to create a stupidly simple bit of kit that matches my rudimentary fabricating skill level with my desire for reliability and functionality. I’d probably go to a bike shop or a metal shop for the crucial, finicky bits.

Any advice really appreciated.

 

4E0EA0F3-BBA8-4212-94E4-3B0C6901F842.jpeg

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I'm not the expert, but there are compromises with every great pedal drive idea. I was planning to do a flexible shaft with a universal joint, but it turns out that there is a lot of power loss from a universal joint and the loss increases as the angle increases.

I really hope that I get to see the pedal drive that Rick posted a photo of just above. It looks kind of insane, but it might be brilliant.

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11 hours ago, phillysailor said:

My goal is to create a stupidly simple bit of kit that matches my rudimentary fabricating skill level with my desire for reliability and functionality. I’d probably go to a bike shop or a metal shop for the crucial, finicky bits.

I have the same requirement, and I am thinking more along these lines:

Harry Bryan's Thistle with fish fin drive  If you attach this to your front crossbeam, it will have minimal effect on steering.

Treddlecat  I expect that connecting the cranks with a line run through a block will create a one-sided version of this.

 

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It's not for the R2AK this year, but a professor of zoology at Oxford, Adrian Thomas, is working on a whale tail as a propulsion mechanism that has a 20–30% efficiency gain over a propeller and works over a higher range of speeds.

With the craft shown below, Malolo, he hopes to break the human-powered 20 knot barrier this summer. The podcast from the BBC is pretty good with the specific human-powered water propulsion stating at 25:30. Sell your quadcopter.

https://player.fm/series/the-life-scientific-1301276/adrian-thomas-on-the-mechanics-of-flight

 

p05gtznq.jpg

 

 

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20 minutes ago, t.rex said:

It's not for the R2AK this year, but a professor of zoology at Oxford, Adrian Thomas, is working on a whale tail as a propulsion mechanism that has a 20–30% efficiency gain over a propeller and works over a higher range of speeds.

With the craft shown below, Malolo, he hopes to break the human-powered 20 knot barrier this summer.

 

It is possible to make marine propellers with 90% efficiency so it is impossible to exceed that by 20 to 30%.

The aspect and size of that blade would not enable 20 knots with human power.  They will be lucky to get 10kts.  There is much development to go yet.

The POMS are not the engineers they used to be.  Their top engineers were 6 generations ago.  The linked clip gives details of a water human power world record attempt a couple of years ago.:

Clearly the 5.54mph achieved is a dismal fail compared with the MIT record of 21mph!

I did serious evaluation of oscillating foils and was very impressed with the way they worked and how to get maximum efficiency.  However some interested bystander once made the comment that there is nothing in nature that can mimmic a rotating shaft and that is why animals flap rather than spin.  He was not quite right because there is a bacteria with a flagellum on a rotating shaft but I think that is the only example in nature.  I set about what I had learnt with the oscillating foil and applied it to the propeller.

There have been quite a few propulsion systems using flapping foils but none of them have achieved the success of propeller; with the exception of the Hobie flappers but they only get about 50% efficiency.  Adrian Thomas would be better off learning more about propellers before making uninformed comments.  I expect he is going through that process now if he is still getting funding.

 

 

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Hi RickW,

I have no dog in this fight, so I'll just make one clarification and let it go.

In the podcast at 25:44, Adrian cites a study by Harvard University which states "the efficiency that you can achieve with that kind of [flapping] propulsion is higher than that you can get out of a propeller, and the gain has been experimentally shown to be about 20 to 30%." I don't know the bibliography of the Harvard publication.

I'll let you know how the record attempt goes.

 

 

 

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