Boat Design Forums  |  Boat Design Directory  |  Boat Design Gallery  |  Boat Design Book Store  |  Thanks to Our Site Sponsors

Go Back   Boat Design Forums > Design > Boat Design
Register FAQ Members List Calendar Search Today's Posts Mark Forums Read Most Recent Posts Gallery Images Search

Reply
 
Thread Tools Search this Thread Display Modes
  #1966  
Old 08-30-2014, 01:50 PM
jehardiman jehardiman is offline
Senior Member
 
Join Date: Aug 2004
Rep: 2027 Posts: 2,087
Location: Port Orchard, Washington, USA
Quote:
Originally Posted by Yobarnacle View Post
Here is a youtube of interest and the quote is the blurb beneath the video.
https://www.youtube.com/watch?v=8I-H47uuQF0

"Uploaded on Oct 14, 2010
Testing a 40lb trolling motor on a Cobra Fish N Dive kayak. The first bit of footage shows use with the standard propeller and the second bit (final 25%) shows use with an 10 x 4 model aircraft propeller. We tested the standard prop as well as 3 other props of varying pitches. The standard prop gave a top speed of around 8km/h and drew 33 amps whilst the aircraft prop that came out in front gave a top speed of around 10km/h and drew 29 amps. The other pitches (10x6 and 10x8) gave slightly better speed but used too much power.
That is exactly as expected given the displacement/ length of the hull and design rational of a trolling motor. I also bet the 10x4 took longer to accelerate the boat...which is the exact opposite of the design goal of a trolling motor. There are so many nuisances to propeller design, especially when working on HPV which are such a small scale where you are not running up against practical limits (such as root bending and submergence drafts). Going to an 11x3 would most likely lower the amps even further for that speed.
__________________
A vessel is nothing but a bunch of opinions and compromises held together by the faith of the builders and engineers that they did it correctly. Therefor the only thing a Naval Architect has to sell is his experiences.
Reply With Quote


  #1967  
Old 08-30-2014, 02:23 PM
portacruise portacruise is offline
Senior Member
 
Join Date: Jun 2009
Rep: 218 Posts: 866
Location: USA
TC:

The MK speed control claim to go 5X longer needs to be qualified for a particular low speed. The mechanical switch system of cheaper motors is slightly more efficient at FULL speed, where most troll motors are used for the greatest time...

There is also somewhat of a myth about motor cooling with a submerged troll motor head which only cools the field magnets directly. This is because of the insulating air gap between the centrally located hot armature and brushes doesn't allow for efficient cooling. Better to go with an electronically commutated outrunner motor for efficiency and cooling....

We may be getting off topic here, so perhaps should move to the electric boat thread?

PC

Quote:
Originally Posted by TomCat58 View Post
portacruise: Thank you

Yes any drag effects the performance so I design the pontoons to barely touch the water on just the rear sections while cruising. As the need increases the pontoons use more of there surface to stabilize.

The trolling motor is very affordable and yes not so efficient but with a limited budget its working ok. I did however buy one of the newer Minn Kota's that claim to go 5x longer then some of their other cheaper models. It has a computer control board using a pulse system. The other factor is the trolling motor is almost water proof. Everything on this canoe has or will get wet sooner or later. The trolling motor has come off once while the boat was tied up on a sandy shore. I got it out of the 2 feet of water and dried it the best I could and it works just like new :-)

Thank you for your comments I am on a constant learning curve to improve my canoe. The next improvement I think I will make is to replace the two 29 series deep cycle batteries with Lithium Lifepo4 electric car type batteries.

That improvement from my research promises to greatly improve speed and extend how long the batteries last.

TomCat
Reply With Quote
  #1968  
Old 08-31-2014, 10:02 PM
TomCat58 TomCat58 is offline
Junior Member
 
Join Date: Dec 2013
Rep: 14 Posts: 12
Location: Washington State
Electric boat thread ?

PC,
Yes your correct this has gotten off topic here. Where should I post at to keep it going?

I am trying to move this thread to the electric boat thread but am not having any luck finding it. I see gas powered, diesel powered but no solar or electrical powered ?

Thanks
TomCat
Reply With Quote
  #1969  
Old 08-31-2014, 11:08 PM
TomCat58 TomCat58 is offline
Junior Member
 
Join Date: Dec 2013
Rep: 14 Posts: 12
Location: Washington State
OK this thread has been moved to:


http://www.boatdesign.net/forums/boa...gns-19444.html

Small boats and Solar Power
Reply With Quote
  #1970  
Old 09-01-2014, 10:05 PM
P Flados P Flados is offline
Senior Member
 
Join Date: Oct 2010
Rep: 348 Posts: 511
Location: N Carolina
The link above should have been Small boats and Solar Power
Reply With Quote
  #1971  
Old 09-01-2014, 11:55 PM
TomCat58 TomCat58 is offline
Junior Member
 
Join Date: Dec 2013
Rep: 14 Posts: 12
Location: Washington State
Thank you Flados..... I am still trying to figure out this forum and how it functions..
Reply With Quote
  #1972  
Old 09-01-2014, 11:59 PM
Yobarnacle's Avatar
Yobarnacle Yobarnacle is offline
Senior Member
 
Join Date: Nov 2011
Rep: 805 Posts: 1,311
Location: Mexico, Florida
Quote:
Originally Posted by TomCat58 View Post
Thank you Flados..... I am still trying to figure out this forum and how it functions..
Me too!
__________________
:D "The Titanic was the finest ship afloat, ten minutes before it encountered Reality." https://www.youtube.com/watch?v=h3BJl5Zy7HQ
Reply With Quote
  #1973  
Old 09-02-2014, 02:27 AM
Leo Lazauskas's Avatar
Leo Lazauskas Leo Lazauskas is online now
Senior Member
 
Join Date: Jan 2002
Rep: 2122 Posts: 2,487
Location: Adelaide, South Australia
Quote:
Originally Posted by jehardiman View Post
And that is for dead flat calm, so add 20-30% seaway margin for real conditions. 74-79 watts is ~ 1/10 Hp sustained, which is approaching serious amateur cyclist ability.
I'd also add a bit more if the hull isn't going to be kept very clean.
And more for any appendages, especially if they aren't filleted well.
Reply With Quote
  #1974  
Old 09-07-2014, 02:00 AM
Rocky Mtn Russ Rocky Mtn Russ is offline
Junior Member
 
Join Date: Aug 2014
Rep: 10 Posts: 8
Location: Colorado
Thanks guys for all of your comments and advice. Not sure why I stopped getting notice that posts were happening. I've been struggling to learn Free!ship, and emailing with Rick W. about some of his designs. He's been very helpful too.

The numbers Dave generated actually sound pretty good to me.

On our latest 10 day kayak trip, my tandem island Hobie with twin mirage drives was loaded heavier than usual. Speed fell off considerably as a result. That boat is 18.5 feet, with a 30" beam, and would have tipped the scales around 840 lbs. The boat is 190 lbs empty. There were 2 of us onboard, and a bunch of gear in the hull and lashed to the tramps. It was a challenge to sustain 3.2 mph on our 10-12 mile ride out to our camp into about a 15 mph headwind. Typically, that boat with 2 guys peddling will do 4.0 mph continuous, and 3.7 if I'm by myself without the sail and outriggers. One of the guys was in a 13.5 foot, 28 inch beam Hobie, with camping gear, and he sustained 4.2 mph on the ride back, in fairly flat water. That was fast for that short boat.

I also have a wooden sea kayak, that I'm fairly experienced in. I've done up to 5 days camping in that boat, but the volume is pretty low, and I don't like strapping stuff to the decks. It's a speedy boat at 17.5 feet and 22.5 inch beam, and only 40 lbs empty. But not big enough for me to carry enough camping gear, and not stable enough to fish... which would be awkward while holding a paddle.

I'm in agreement with the comments about 10 inches of freeboard, and windage. But to add a peddle drive, at least some of the deck must be open. And to carry more gear, I need either width, height, or more length. At least height is above the waterline and helps towards the drier ride my wife is looking for. I'll see what I can do to deal with these conflicting goals. My design already includes both stern and bow rudders (the bow rudder is 3 feet back from the bow).

Currently, the outriggers are 5.4 inches wide at their widest, and 5 feet long. I don't have any numbers on them yet, but they look pretty sleek in freeship so I didn't think they'd be too draggy.

I've also been looking at a flexible shaft combined with a drive leg. Does anyone know about flexible shafts? The specs on them sound great, and there's a company in Canada using them as after-market drives for canoes and kayaks. I may still use the 5/16 steel shaft with Rick's prop, but if I can keep from having 8 feet of steel in the water, I'd prefer to... I'm sure I'll be snagging my fishing line if I'm landing a big one on that side of the boat.

Thanks for all the great help!

Russ
Reply With Quote
  #1975  
Old 09-07-2014, 12:09 PM
portacruise portacruise is offline
Senior Member
 
Join Date: Jun 2009
Rep: 218 Posts: 866
Location: USA
Quote:
Originally Posted by Rocky Mtn Russ View Post
Thanks guys for all of your comments and advice. Not sure why I stopped getting notice that posts were happening. I've been struggling to learn Free!ship, and emailing with Rick W. about some of his designs. He's been very helpful too.

The numbers Dave generated actually sound pretty good to me.

On our latest 10 day kayak trip, my tandem island Hobie with twin mirage drives was loaded heavier than usual. Speed fell off considerably as a result. That boat is 18.5 feet, with a 30" beam, and would have tipped the scales around 840 lbs. The boat is 190 lbs empty. There were 2 of us onboard, and a bunch of gear in the hull and lashed to the tramps. It was a challenge to sustain 3.2 mph on our 10-12 mile ride out to our camp into about a 15 mph headwind. Typically, that boat with 2 guys peddling will do 4.0 mph continuous, and 3.7 if I'm by myself without the sail and outriggers. One of the guys was in a 13.5 foot, 28 inch beam Hobie, with camping gear, and he sustained 4.2 mph on the ride back, in fairly flat water. That was fast for that short boat.

I also have a wooden sea kayak, that I'm fairly experienced in. I've done up to 5 days camping in that boat, but the volume is pretty low, and I don't like strapping stuff to the decks. It's a speedy boat at 17.5 feet and 22.5 inch beam, and only 40 lbs empty. But not big enough for me to carry enough camping gear, and not stable enough to fish... which would be awkward while holding a paddle.

I'm in agreement with the comments about 10 inches of freeboard, and windage. But to add a peddle drive, at least some of the deck must be open. And to carry more gear, I need either width, height, or more length. At least height is above the waterline and helps towards the drier ride my wife is looking for. I'll see what I can do to deal with these conflicting goals. My design already includes both stern and bow rudders (the bow rudder is 3 feet back from the bow).

Currently, the outriggers are 5.4 inches wide at their widest, and 5 feet long. I don't have any numbers on them yet, but they look pretty sleek in freeship so I didn't think they'd be too draggy.

I've also been looking at a flexible shaft combined with a drive leg. Does anyone know about flexible shafts? The specs on them sound great, and there's a company in Canada using them as after-market drives for canoes and kayaks. I may still use the 5/16 steel shaft with Rick's prop, but if I can keep from having 8 feet of steel in the water, I'd prefer to... I'm sure I'll be snagging my fishing line if I'm landing a big one on that side of the boat.

Thanks for all the great help!

Russ
Russ:

Do you have a link on the company in Canada, that you write about? Curious as to how they have set it up.
Rick has tried different materials for flex shafts including CF, SS and spring steel. SS spring has been hard to find in the US in the past, and the CF (much larger diameter compared to others) was custom made for him. You can experiment with long electrician drill bits and sewer rod to get an idea for your project. You can avoid some fishing tangles by using a pontoon design and mounting the shaft drive between, but it will be a slower boat. It might serve you just as well to use a thinner, stronger, rust proof steel straight shaft which is less costly and easy to source. Your bends can be done with compact universal joints similar to those found on ratchet tools sets, if you will be mounting a skeg type bearing. Flex shafts are at their best when they can run directly and untethered without bearings because this allows them to conform to obstructions, be easily pulled up for beaching and even for steering instead of a rudder: Prop Shaft Systems. post #53, 54

The HP speed you desire may be not be sustainable in wind and waves as the outriggers will hang up/cause control issues and be an additional drag. Maybe a small, lightweight backup motor would be the way to go: http://www.electricpaddle.com/products.html

Hope this helps.

PC
Reply With Quote
  #1976  
Old 09-07-2014, 12:44 PM
Rocky Mtn Russ Rocky Mtn Russ is offline
Junior Member
 
Join Date: Aug 2014
Rep: 10 Posts: 8
Location: Colorado
PC: that link is http://h2proped.com/index.htm You'll see his flexshaft is encased. Those are the ones I've been studying. They're no good under water though, hence the drive leg. I've actually designed a drive leg that uses a twisted timing belt on small pulleys driven directly by the pedal crank shaft. The drive can kick up if it strikes something. I'd have to test the drive leg to check the durability of running the belt with a twist. Rick had sent me a link to an outfit that is doing something very similar except theirs has 4 turns of 90 degrees.

In any case, my 2.5 hp 4 stroke Suzuki (30 lbs) will be mounted onboard as a backup or for those really long excursion days.

The real issue with getting a dryer ride is to raise the seat or the freeboard. I'm taking a hard look at using the low, self bailing deck that Rick has popularized, and just raising the deck under the seat area and maybe a second small bump in the back if more storage is needed. I'm also going to study adjustable width stabilizers to see what that looks like. Thanks again.

Russ
Reply With Quote
  #1977  
Old 10-29-2014, 12:01 PM
GMR GMR is offline
Junior Member
 
Join Date: Sep 2011
Rep: 22 Posts: 54
Location: Nova Scotia
Summer 2013 I got to spend quite a bit of time pedalling the Chameleon pedal cat. The performance was a little less than desired (underwhelming someone said but probably on par with what many of you would have predicted. ( I now have a GPS so I can get better numbers) .... 40 or 50 kilometer days on relatively calm ocean were quite reasonable with just me pedalling. It turned out to be easy to manage with one or two people pedalling and light enough to drag on or off the beach by myself. Although each hull has approximately 500 pounds buoyancy it isn't enough with a pair of 200 pound people on board. If I had to crawl out to the stern to deal with a rudder issue the stern of both hulls was under the water. As wave height increased the ride got wetter.

I had planned on building a Scarab 650 Sport sailing trimaran and had just started the machining for the metal parts of the folding amas When my stroke hit. I have decided to hold off on this project and tackle something else until I get back up to speed. Last winter I bought a Prindle 19 beach cat to use as a doner for outriggers and sailing rig for the trimaran.

One option is to adapt the Chameleon frame and deck to fit with these hulls. Or use the Prindle cross bars with the Chameleon deck and pedal drives etc. Should be more seaworthy but heavier too and maybe even slower.

I have always been intrigued by Coach Dave's boat as the base for a multiple person craft and I was quite interested in the conversations with Rocky Mtn Russ who was planning something close to what I am considering. Two pedal drives with extra seats appropriate for paddling. A small simple sailing capability, and I still have a large kite that I have not had a chance to try.

Without getting a caculator out yet, I was thinking hull 24 to 26 feet long, 24 to 28 inch beam, single or double outriggers at 6 to 8 feet long with semi planing hulls. Not quite sure what shape to make the main hull especially closer to the stern.

Any comments?
Reply With Quote
  #1978  
Old 11-02-2014, 05:34 PM
Coach Dave Coach Dave is offline
Junior Member
 
Join Date: Jun 2011
Rep: 40 Posts: 70
Location: Malabar, FL
Quote:
Originally Posted by GMR View Post
Summer 2013 I got to spend quite a bit of time pedalling the Chameleon pedal cat. The performance was a little less than desired (underwhelming someone said but probably on par with what many of you would have predicted. ( I now have a GPS so I can get better numbers) .... 40 or 50 kilometer days on relatively calm ocean were quite reasonable with just me pedalling. It turned out to be easy to manage with one or two people pedalling and light enough to drag on or off the beach by myself. Although each hull has approximately 500 pounds buoyancy it isn't enough with a pair of 200 pound people on board. If I had to crawl out to the stern to deal with a rudder issue the stern of both hulls was under the water. As wave height increased the ride got wetter.

I had planned on building a Scarab 650 Sport sailing trimaran and had just started the machining for the metal parts of the folding amas When my stroke hit. I have decided to hold off on this project and tackle something else until I get back up to speed. Last winter I bought a Prindle 19 beach cat to use as a doner for outriggers and sailing rig for the trimaran.

One option is to adapt the Chameleon frame and deck to fit with these hulls. Or use the Prindle cross bars with the Chameleon deck and pedal drives etc. Should be more seaworthy but heavier too and maybe even slower.

I have always been intrigued by Coach Dave's boat as the base for a multiple person craft and I was quite interested in the conversations with Rocky Mtn Russ who was planning something close to what I am considering. Two pedal drives with extra seats appropriate for paddling. A small simple sailing capability, and I still have a large kite that I have not had a chance to try.

Without getting a caculator out yet, I was thinking hull 24 to 26 feet long, 24 to 28 inch beam, single or double outriggers at 6 to 8 feet long with semi planing hulls. Not quite sure what shape to make the main hull especially closer to the stern.

Any comments?
That would be a shorter version of Scott Reeves' Third Wheel. https://www.mail-archive.com/hpv-boa.../msg00084.html
Pedal drive for 2 people, a third seat for paddling or resting.
Reply With Quote


  #1979  
Old 11-05-2014, 01:18 PM
GMR GMR is offline
Junior Member
 
Join Date: Sep 2011
Rep: 22 Posts: 54
Location: Nova Scotia
Thanks for that, I don't remember ever seeing that craft before. I am looking for more of a a sit-in boat to use in open water. To that end I looked at large canoes but most in the 20 to 30 foot length come with a beam of up to 5 feet! So I looked at outrigger canoes and found an OC4 from Clipper Canoe in British Columbia. The main hull is 31 feet long and 18 inches wide. Not sure on the price for just the main hull but the complete boat is about 9 grand (CDN$) plus another thousand to ship to the other side of the country. This is not on their website right now because they are modifying it to put a rudder on the stern.

The Chameleon hulls were built with flat plywood tops and sides with round cedar strip bottoms.
In the small trimaran world Frank Smoot has a boat called LocoMotion that uses plywood bottom and sides, then he glues foam on the bottom to get the shape he wants for the bottom. I have seen others use cedar strips on the transition from bottom to side with great results. The foam is soft and heavy so I would not use that method. Using lee boards for sailing means they can be out of the water the rest of the time. I would put two pedal drives through the bottom, though I would like to buy them this time instead of making them but we'll see. Lots of freeboard on this example which would make it even harder to go upwind. Any masts and sailing rig would have to disappear when pedaling for the same reason. Just some thoughts anyway..... Glen
Reply With Quote
Reply



Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes


Similar Threads
Thread Thread Starter Forum Replies Last Post
Propellor for pedal powered catamaran Tiny Turnip Props 38 03-18-2013 11:03 PM
Electric motors for solar-powered boats Twointense13 Boat Design 3 01-07-2011 09:21 PM
Windmill or Wind Turbine- powered boats: how many are out there, and are they viable? Duma Tau Projects & Proposals 503 08-13-2010 03:00 PM
Human-powered boats and submersibles RatliffFranklin Boat Design 0 05-08-2007 02:36 PM
Bugatti engine powered boats rivaaquarama Powerboats 0 06-08-2006 05:26 PM


All times are GMT -4. The time now is 10:48 PM.


Powered by: vBulletin Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Web Site Design and Content Copyright ©1999 - 2014 Boat Design Net