Paddle Design Stability

In this post I want to focus on ways to design a paddle so it orients itself in the proper direction for paddling without a lot of effort on the part of the paddler. A paddle that requires a tight grip to keep it in control will sap the energy of the paddler and cause fatigue and diminished efficiency.
Not surprisingly, there is more than one way to make paddle orientation easier to control. I will examine three different ways all of which can be used in various combinations. I should also mention that the intended use of the paddle, whether it is meant for racing, cruising, surfing or rolling will have an impact on how it should best be held.
Most traditional paddles have oval or egg shaped looms with the longer dimension of the oval perpendicular to the face of the paddle blade. The oval shape makes it easier to keep the loom from twisting in the hand than a loom with a circular cross section.
A second way to keep the loom from twisting in the hands of the paddler is to hold the paddle at least partly by the root of the blade where it joins the loom. For instance, in a shouldered Greenland paddle, the index finger and the thumb circle the loom while the other fingers and the rest of the palm circle the root of the paddle blade. The flat part of the blade resting against the flat of the palm gives the paddle stability and keeps it from rotating in the hands of the paddler.
I thought at one time that it was only the Greenland paddles that were held this way, but there are some photos of Unangan (Aleut paddlers) that also show them holding their paddles so that at least part of their hand is on the root of the blade and part on the loom.
A third way to stabilize a paddle is to design it so that the paddle blade naturally wants to orient itself in the right direction when the paddler pulls on the loom. This trick only works for paddles that are asymmetrical, that is paddles that have a front face that is different from the back face. When you pull this kind of paddle through the water at some random angle, it will have one face that will naturally orient itself in the direction of travel while the other face orients itself away from the direction of travel. It is like a wind vane which if put sideways into the wind will turn its head into the wind and its tail out of the wind. Examples of this kind of paddle are the Unangan (Aleut) paddle and bent shaft paddles in which the face of the blade slightly trails the loom as the paddle is being pulled through the water.


In these two closeups of Unangan paddlers from the same boat, both paddlers are holding the paddles with the flat face toward the back.  The interesting thing with these paddles is that the weather vane effect would favor holding the paddles flat face toward the front but the shape of the paddle in the areas where paddlers held it also make the opposite orientation stable. The photo was no doubt posed and both paddlers are just holding the boat in position rather than paddling forward.  They may actually be paddling backward. So it is hard to tell whether this is the way they held their paddles when moving along, but regardless of what was happening when the picture was taken, it seems that the shape of the loom allows the paddle to be held in a stable manner regardless of orientation.
This also brings us to the question why so many commercial paddles have looms with round cross sections while traditional paddles almost without exception have looms with oval cross sections.  I suspect the reason is that is simply so much easier and cheaper to manufacture looms with round cross sections.
Read More..

How Many Kayaks Are There

I lifted this photo off facebook.  It shows a bunch of kayaks and canoes all rafted up together to set a Guiness Book world record.  The photo came with the following info:
"The largest raft of canoes and kayaks consisted of 1,902 boats and was achieved at the event "One Square Mile of Hope". The event was sponsored by the Central Adirondack Paddlers Society, and took place on Fourth Lake in Inlet, New York, USA!"
The photo got me to thinking, how many kayaks are there in the world right now?  Probably lots and lots, maybe even millions, thanks to the miracle of injecting plastic into a mold.  This is not intended to be a slam on plastic kayaks by the way.  Even home built skin on frame kayaks in the world right now must come close to the number of skin kayaks that existed at the peak of population in the Arctic. 
Aleut population at its maximum was estimated to be about 20,000.  Perhaps a third of that population was adult males each of whom supposedly had a kayak. So at its peak, there were perhaps 7000 kayaks in the Aleutians. 

Read More..

Iqyax Baidarka Research


I am currently working on the improved Bay Boat, that is, San Francisco Bay Boat.  The baidarka I had been paddling most frequently is about 20 years old, re-ribbed once and reskinned a number of times and a fairly close replica of an Atka baidarka.  This particular boat just got a paint job.  The old paint job consisted of a varnish base covered some time later by a color coat.  The color coat was peeling badly, probably because I never sanded the base coat before putting on the color coat.  The re-paint is done now.
 

The baidarka is on the left with its new coat of gray latex house paint.  I store my boats outside so the most critical job of the paint is to keep the UV rays from degrading the nylon skin.  Opaque paint does a good job of that and more cheaply than exterior varnish.  Thats my King Islander to the right of the baidarka.
The only drawback of the old baidarka is its narrow width and fairly deep hull which makes it a challenge to keep upright.  Its actually not that bad once you get used to it, but its not a boat that you can just sit in and relax.  When youre not moving, you need to brace or have the paddle out as an outrigger.  
So, enter a wider version of the Atka iqyax^.  The idea behind this boat is sufficient width to allow lounging without constant bracing but not enough width to make it slow, a boat suited for longer stays on the water, like a bay crossing, about a one hour affair.
Inside view of the hull.  Good width and flat rib profile to make the boat stable. 
And an outside view of the hull with the stringers temporarily taped and lashed in place.  Also note the open jawed bow, a configuration I have been playing with, mostly because this configuration makes it easier to align the keelson with the bow assembly.
Also the upturned nose of the other bow configuration is more prone to breaking because the grain runs across the upturned part instead of in line with it. 
Read More..

Yurt Design Canvas Shrinkage

Canvas shrinks.  I knew that. So when I designed the roof pattern for the yurt, I should have allowed for shrinkage but didnt.  Oh well, nothing that cant be fixed with a little more sewing.
Not only didnt I allow for shrinkage in the roof, I also didnt realize that the canvas shrinks unevenly, more along the length of the material than across it.  Something to be conscious of next time.
Now that I think of it,  I doubt that I could plan for shrinkage in any sort of exact way since the shrinkage is non-isotropic.  I suppose I could just make a roof cover uniformly oversize, then when it shrinks, regardless of whether it does it evenly or not, it would still be large enough to do the job.
For now, not having tried to it yet, I am leaning toward pre-shrinking the canvas.  Unroll however much canvas I need, hose it down, dry it in the sun, then cut it up and sew it into whatever shape I need. Everything I havent tried yet sounds like a good idea.  Whether it actually is, doing it will tell.
Meanwhile, some before and after shrunken roof cover pictures.
Before: the yurt roof cover on its maiden voyage in Kings Canyon National Park. I trimmed the fabric so there would be about 8 inches of overhang.  Sewing the seam at the edge reduced that by about an inch.  Other than the wrinkles which I hadnt dealt with yet, not bad.
After: Overhang of the roof fabric has been reduced to about 4 inches at the max and two inches at the minimum.  The wall fabric likewise has shrunk some top to bottom and side to side. Time to make some corrections. Canvas work is not an exact science.



Read More..

Paddle Design Prologue

Ive had two different prototype paddles kicking around for a while that I was not able to get to the point where I liked them.  What I typically do when I build new paddle designs is to overbuild them and then whittle away at them until they work to my satisfaction, or at least until their performance does not improve any more. Sometimes, it is just not possible to rescue a paddle design.  I have to walk away from some paddles and simply write them off as a learning experience. I generally have no idea how a new paddle will work until I actually try it out.  I would like to say that the more paddles I build, the better I get at predicting paddle performance, but I would be lying.  The only way I can tell what design will work is to actually build it and try it out. 
 

I should also mention that a paddle must be matched to the boat as well as the paddler to perform well.  A paddle is not a good paddle in the abstract.  A paddle is a good paddle only for a specific set of conditions.  In this case, I happened to have my King Island kayak readily available and that became the test platform.  The King Island kayak was fairly well suited to this particular paddle test because the King Island kayaks high deck calls for long paddles and the set of paddles I was testing were fairly long, 98 inches.  I had already modified both paddles based on previous tests. One paddle had started out at 102 inches long and I cut it down and the other had a loom that was way too fat for comfortable use and I had slimmed down the loom on it.  The thing about the fat loom was that it felt good in the shop, but out on the water in action, it was just too bulky.
Heres a shot of the inside of the King Island kayak. Note the high deck ridge.  The thing about a high deck is that it forces you to hold the paddle up higher which means that it has to be longer to reach the water.
And here is a shot of the two test paddles on the deck of the kayak.  The lower paddle was based on a paddle shown in an old illustration. The upper paddle is a breakdown version of a more conventional Unangan shape except for the loom.

Both paddles are versions of an Unangan (Aleut) design. The Unangan paddles are asymmetrical with the loom offset from the plane of the blades. 
And so I had my test paddles, test boat and test pond, San Francisco Bay.  Even though I had whittled away at both paddles and tried to improve their feel, I preferred the one piece paddle because it was lighter and seemed to move the boat with less effort.  The breakdown paddle felt heavy and more ponderous in the water. 
After the initial test I did a little more whittling and then took out both paddles again and this time I had my GPS with me.  The GPS gives me a speed readout which I can use to measure top speed for a boat or paddle and if I have two or more paddles, it gives me top speed for comparative effort.  Effort expended is pretty much a subjective measure but on a given outing, swapping paddles back and forth several times gives me a pretty good idea of comparative efficiency of two paddles.
And this is where the GPS comes in.  Although one paddle may feel better than another the one that feels worse may actually be giving me a better top speed. It may feel worse because it moves more water and makes me work harder.  But if I am simply cruising, comfortable feel of a paddle may be more important than top speed. Comfortable feel may also be an indication of better efficiency of one paddle over another. 
So to sum up, paddle design for me is a pragmatic exercise.  I have to test paddles on the water to tell whether they are any good and results are often surprising.  In a future blog, I will get more specific on factors that make for a good match between paddler, boat and paddle.









Read More..

Design your own boat online free

Design your own boat online free Instant flash banner maker | html5 banners | custom web ad, Complete flash advertising solution, from banner generator to custom rich media ad design to ad serving and tracking. Maploco! - web visitor map - visited states map, Maploco provides a free map that shows the location of visitors to your website or blog.
Read More..

Design your own boat online Learn how

Pictures Design your own boat online Cross Stitch Sampler Patterns Boat Names Ideas Car Window Decals DIY Pontoon Boat Plans Make Your Own Treasure Map
Read More..

Design your own boat online game

Design your own boat online game Make your own quiz for facebook, blogs, web sites, Take our fun quizzes, or create your own for facebook, twitter, forums and blogs. create a poll or explore our lively forums. Create your own snowflake - ze's page :: zefrank.com, Create 3d snowflakes on zefrank.com Instant flash banner maker | html5
Read More..

Motor boat design pdf Details

Some images on Motor boat design pdf Wooden Runabout Boat Plans Free Model Boat Plans Wooden Boat Building Plans 1920 Yacht All-boats-0041.jpg
Read More..

Yacht and boat design school

Yacht and boat design school Yacht design school, small craft, boat, naval architecture, Yacht design school teaches a complete curriculum in yacht and small craft design. we offer both correspondence and residential opportunities. a primary goal is the American boat and yacht council (abyc): welcome, (abyc) - develops consensus safety standards for the
Read More..

Boat ramp design guidelines

Boat ramp design guidelines Ferry Boat Toys Plastic Boat Seats Norwegian Architecture Road Safety San Luis Reservoir
Read More..

Design your own boat wrap online Guide

one photo Design your own boat wrap online With Bangs Cornhole Boards Clip Art Design Your Own Tattoo Software Boat Names Car Decals and Graphics
Read More..

Solar boat design pdf

Solar boat design pdf LEGO Logo Font Iridium Satellite Phone Small Boat Anchor Pirate Ship Diaper Cake Armidale Class Patrol Boat
Read More..

Vector boat wrap design Diy

Some images on Vector boat wrap design UCLA Campus Map Los Angeles Dragon Car The guarding angels click here to buy now About Signs of Seattle Scion Style Vehicles Wraps
Read More..

Boat graphics design your own

Boat graphics design your own Boat Lettering Vehicle Lettering Wall Lettering Custom Boat Wraps Boat Decals and Lettering Boat Striping and Graphics Speed_Boat%20Name-Tomahawk.JPG
Read More..

Boat molds for sale design

Boat molds for sale design Boat molds | allmand boats | boat molds for sale, Shop for high quality boat molds at very cost effective solution at allmandboats.com. Boats for sale - the hampton one design class, Boat # description. asking. contact hampton one design: wooden hull. $14,000 obo. 33. tom monath: tpmonath@gmail.com hampton one design, hull
Read More..

Rhino 5 boat design Learn how

Pic Example Rhino 5 boat design More honda Concept Boats Shrimp Trawler Posted by Vaughan Ling at 8:51 PM No comments: Peugeot 208 - Design Sketch
Read More..

Boat design category c

Boat design category c Amels199.com 285 Conquest About 1952 Jaguar C-Type Roadster Ashi Te Do
Read More..

Understanding boat design pdf Details

Some images on Understanding boat design pdf Sailing Ship Deck Plans Stuur je mooiste mobiele vakantiefoto op met dit formulier en maak Woodworking Projects That Sell SWITCHABLE RATCHETS Photo1.pdf (388.1 KB, 78 views)
Read More..

Free wooden boat design

Free wooden boat design Storer wood and plywood boat plans, Wooden and plywood boat plans for amateur boatbuilders � excellent performance, simple construction, detailed step by step instructions for boats, canoes and Free boat design resources - what's new, Links to articles, essays, boat design software and even a number of free small boat designs,
Read More..



Blog Archive

Diberdayakan oleh Blogger.