Bob Hoerger of Palo Alto brought the following ad from the November 1940 issue of Pacific Motorboat to my attention:
FOR SALE: Genuine Eskimo kayak with skin cover, recently brought from Alaska. Well constructed. Balances easily. Good for fishing and sport on river, lake, or bay. M. Lantis, Berkeley, Calif.
Some of you may recognize M. Lantis as the woman who collected the baidarka in the collection of the museum of anthropology at the University of California in Berkeley. Whether this was another kayak or the one that is now in the museum is not known. This ad was placed in 1940 and the boat in the museum was collected in 1934 and is lacking its skin. But who knows. M. Lantis may have tried to sell the boat, not found a buyer, stripped off its skin and then donated it to the museum.
Sunday, July 20, 2008
Skinboat Rendezvous
We had a skinboat rendezvous yesterday in Alameda. Several skin boat builders brought their boats for review by each other and the general public. Thanks to a notice in the San Francisco Chronicle, quite a few people turned out. Fellow skin boaters Tony Mullins and Dave Browne did much of the heavy lifting. Dave Browne did the majority of the promotional work and organization of the event. I just showed up with boats and brats, that's bratwurst for the uninitiated. I got so busy talking to people and setting them up with boats that I forgot to take pictures except at the start of the event. Oh well.
Here's Tony on the left and Dave on the right unloading boats at Encinal beach.
Encinal beach wasn't far from my shop so I was able to pile a bunch of boats on top of my car without tying them down carefully.
Here's Tony on the left and Dave on the right unloading boats at Encinal beach.
Encinal beach wasn't far from my shop so I was able to pile a bunch of boats on top of my car without tying them down carefully.
Tuesday, July 15, 2008
Trinidad
No, not the one in the Caribbean, the one in Northern California.
This is where the Arcata crowd paddles. Trinidad Head, a big rock connected to the coast by a low land bridge blocks the prevailing NW swell and forms a natural harbor in its shadow.
Here's the view to the northeast and the unprotected beach. If the swell is low, people can take off here with their kayaks.
Here's a view southeast, the sheltered water and natural harbor in the shadow of Trinidad head. Here paddlers can launch even when swells are running 20 feet. They can paddle sheltered water all day or nudge their way around the corner and push into the swell for big elevator rides or head for the shore for some rock gardening.
This is where the Arcata crowd paddles. Trinidad Head, a big rock connected to the coast by a low land bridge blocks the prevailing NW swell and forms a natural harbor in its shadow.
Here's the view to the northeast and the unprotected beach. If the swell is low, people can take off here with their kayaks.
Here's a view southeast, the sheltered water and natural harbor in the shadow of Trinidad head. Here paddlers can launch even when swells are running 20 feet. They can paddle sheltered water all day or nudge their way around the corner and push into the swell for big elevator rides or head for the shore for some rock gardening.
Stability, part 2
Scroll down for stability part 1. This is stability part 2. The stability of kayaks is not just an attribute of the boat, but an attribute of a conglomerate of factors. Let me list them:
1) Water conditions
2) Boat shape
3) Boat loading
4) Skill of the paddler
5) The paddle
6) Wind
About the only factors that people typically take into consideration when trying to measure boat stability are factors 2 and 3.
Stability is considered to be a characteristic of the boat and the paddler is victim or beneficiary as the case may be of the boat's inherent stability. But realistically, the paddler has to be considered a part of the boat since he/she not only affects how the boat sits in the water but is also an integral part of its stabilizing system which may include ballast and cargo, but will also include a paddle.
The paddle of a kayak in the hands of a skilled paddler acts like an outrigger and increases the effective width of the kayak from around 2 feet to about 4 to 5 feet, making the boat considerably more stable, so stable in fact that the boat need not capsize except under the most extreme conditions, and if it does, the paddle in the hands of the skilled paddler makes the kayak self righting.
Aside from the skill of the paddler, the second biggest factor that impacts stability of the kayak is its cargo and the weight distribution of the paddler. A kayak by itself is fairly stable. However, a paddler will move the center of gravity upward and make the boat less stable. The heavier and taller the paddler, the worse the effect on stability. The easiest way to counter the weight of the paddler is to add ballast in the bilge of the kayak. According to stability curves published in Sea Kayaker Magazine, ballast has a much greater positive effect on kayak stability than does hull form. But recreational kayaks on day trips are mostly paddled empty so that stability becomes primarily a result of hull form.
The only down side of ballast is that it make the boat harder to propel. Oh well.
Finally, there is the matter of the paddler's skill I will return to this topic at another time, along with the influence of water conditions and wind.
1) Water conditions
2) Boat shape
3) Boat loading
4) Skill of the paddler
5) The paddle
6) Wind
About the only factors that people typically take into consideration when trying to measure boat stability are factors 2 and 3.
Stability is considered to be a characteristic of the boat and the paddler is victim or beneficiary as the case may be of the boat's inherent stability. But realistically, the paddler has to be considered a part of the boat since he/she not only affects how the boat sits in the water but is also an integral part of its stabilizing system which may include ballast and cargo, but will also include a paddle.
The paddle of a kayak in the hands of a skilled paddler acts like an outrigger and increases the effective width of the kayak from around 2 feet to about 4 to 5 feet, making the boat considerably more stable, so stable in fact that the boat need not capsize except under the most extreme conditions, and if it does, the paddle in the hands of the skilled paddler makes the kayak self righting.
Aside from the skill of the paddler, the second biggest factor that impacts stability of the kayak is its cargo and the weight distribution of the paddler. A kayak by itself is fairly stable. However, a paddler will move the center of gravity upward and make the boat less stable. The heavier and taller the paddler, the worse the effect on stability. The easiest way to counter the weight of the paddler is to add ballast in the bilge of the kayak. According to stability curves published in Sea Kayaker Magazine, ballast has a much greater positive effect on kayak stability than does hull form. But recreational kayaks on day trips are mostly paddled empty so that stability becomes primarily a result of hull form.
The only down side of ballast is that it make the boat harder to propel. Oh well.
Finally, there is the matter of the paddler's skill I will return to this topic at another time, along with the influence of water conditions and wind.
Arcata Boat Show
I went up to the Arcata Wooden Boat show in June. Just publishing photos now. Modern boats don't much impress me. I guess it's the esthetics of plywood I'm not in love with. Sure it's practical and easy and strong and low maintenance and waterproof and everything, but it has all the charm of a forest service outhouse.
So there were actually a number of boats at the show that impressed me, but here are the two highlights. Appropriately for redwood country, these boats were made out of redwood.
This boat was no longer in any shape to use, but it was a local adaptation, probably early 20th century to Humboldt bay. It was carved out of a single redwood log. The log had probably been at least 6 foot in diameter possibly 8.
Here's another redwood dugout, this one fashioned by members of the local Indian tribe. I have seen these boats in museums or in photos and they seemed hopelessly ponderous and heavy. Yes they are heavy, but they are not ponderous. They are meant to be river boats and as such have a good amount of rocker and a fairly flat bottom which lets you turn them on a dime. The boat will literally spin on its own axis like a shallow dish. Although the boat weighs about 400 pounds, it is quite nimble and moves along nicely once under way. Plus the center of gravity is so low that you can stand on the gunwales and not tip it over. Sebastian, here pictured jumped up and down on the gunwales without managing to capsize it. Appropriate technology as they say in progressive circles.
So there were actually a number of boats at the show that impressed me, but here are the two highlights. Appropriately for redwood country, these boats were made out of redwood.
This boat was no longer in any shape to use, but it was a local adaptation, probably early 20th century to Humboldt bay. It was carved out of a single redwood log. The log had probably been at least 6 foot in diameter possibly 8.
Here's another redwood dugout, this one fashioned by members of the local Indian tribe. I have seen these boats in museums or in photos and they seemed hopelessly ponderous and heavy. Yes they are heavy, but they are not ponderous. They are meant to be river boats and as such have a good amount of rocker and a fairly flat bottom which lets you turn them on a dime. The boat will literally spin on its own axis like a shallow dish. Although the boat weighs about 400 pounds, it is quite nimble and moves along nicely once under way. Plus the center of gravity is so low that you can stand on the gunwales and not tip it over. Sebastian, here pictured jumped up and down on the gunwales without managing to capsize it. Appropriate technology as they say in progressive circles.
Driftwood Projects, Part 1
Here's a handy dandy kayak rack I made out of driftwood. The driftwood happend to be two by six planks of redwood that were floating around the bay. I ripped them and fashioned an A-frame style rack held together with deck screws, our culture's answer to everything, one step up from duct tape. I wanted to lash the frame together in keeping with the construction of the kayaks, but the screws were just easier. The tarp was meant to keep the sun off the kayaks, not the rain. But the setup was only partly successful, mostly because the tarp was too short. I need to work on that. There are also hellacious winds in the area. On summer afternoons, the wind blows about 20mph off the water, then eddies behind the shop and due to some aerodynamic miracle blows sideways at about 30mph which sets the tarp flapping and snapping something awful.
Arcata Kayak Building Class
I did a Greenland kayak building class up in Arcata, CA. For those of you not into CA geography, Arcata is on the north end of Humboldt Bay which is not too far from the Oregon border and right in the heart of redwood country.
Here's the group with their finished boats. Michael Morris's boat was a little over 17 feet long. Everyone else built 15 footers. They do a lot of rock gardening up near Trinidad so they thought that shorter boats might be handy.
Here's the group on the water in Humboldt bay. The bay is a little warmer than the open ocean, but these guys were more or less duded up for immersion, complete with drysuits and neoprene head gear. The water is cold up there.
Here's the group with their finished boats. Michael Morris's boat was a little over 17 feet long. Everyone else built 15 footers. They do a lot of rock gardening up near Trinidad so they thought that shorter boats might be handy.
Here's the group on the water in Humboldt bay. The bay is a little warmer than the open ocean, but these guys were more or less duded up for immersion, complete with drysuits and neoprene head gear. The water is cold up there.
Wolfgang and the Whale
I did a boat building class up in Arcata, CA. First day I got there, I joined some of the local paddlers on the water. About 15 minutes into the paddle, whales showed up, snorting and breathing deeply and flipping flukes, etc. This was my first whale sighting. No big deal for people on the coast, but my first in 8 years in CA.
It's Been a While
It's been a while since I posted here. I'm back. Been busy actually doing stuff and blogging has taken a back seat. Hard to blog when you're not near your computer and the hardware configuration starts falling apart. My Pentax optio w30 has sort of gone into the tank and I was using it as my bloggo optical recorder on account of its compact size. It still takes pictures but they look like one of the lens elements shook loose and only part of the left half of the picture is in focus while the right hand side gets progressively more out of focus. So I had to revive the old Canon G1 and buy a new battery. etc. etc. Hardware impediments.
Wednesday, May 14, 2008
On the stability of small boats, part 1
This is not going to be a detailed discussion on the stability of small boats. I will actually write something for my website and it will be concise and definitive.
My intent here is merely to commit myself to writing this new page for my web site.
What is prompting me to do it is the persistent mention of secondary stability in kayak and canoe magazines. Three things about this concept.
1) All kayakers use the term as in, "Yeah, I tried that boat. It has low initial stability but good secondary stability."
2) Attempts to find a definition of secondary stability on the internet come up with only a few definitions
3) Such definitions as you can find seem to be subjective and conflicting.
So I will tackle this topic as best as I can.
More to come; stay tuned.
My intent here is merely to commit myself to writing this new page for my web site.
What is prompting me to do it is the persistent mention of secondary stability in kayak and canoe magazines. Three things about this concept.
1) All kayakers use the term as in, "Yeah, I tried that boat. It has low initial stability but good secondary stability."
2) Attempts to find a definition of secondary stability on the internet come up with only a few definitions
3) Such definitions as you can find seem to be subjective and conflicting.
So I will tackle this topic as best as I can.
More to come; stay tuned.
On explaining stuff
Many years ago I had a job as a writer of technical manuals.
If a machine was novel or its working wasn't common knowledge, the manual usually had some kind of theory section in it that explained how the machine worked. The idea was that if you understood how a machine worked, then if you encountered one in a nonworking state, you might have some idea what was wrong with it.
Every once in a while, actually, fairly often, I would get stuck writing these theory sections. What I was writing just didn't sound good. Invariably, after getting up from my desk and walking over to the coffee machine and thinking about the problem, I would discover that the source of my ineffective prose was a lack of understanding of how the machine worked. I was trying to explain something that I didn't understand. I discovered that if I didn't understand something, I couldn't explain it. I further discovered that this rule was pretty much true of anyone who sets out to explain something.
So the next time you read an explanation that doesn't make sense, chances are the person explaining it doesn't understand how it works. Read my next post on stability of small boats for an example of a topic that hardly anyone understands but many people feel compelled to write about all the same.
The other possibility, especially in journalism, when explanations don't make sense, chances are, somebody is lying.
If a machine was novel or its working wasn't common knowledge, the manual usually had some kind of theory section in it that explained how the machine worked. The idea was that if you understood how a machine worked, then if you encountered one in a nonworking state, you might have some idea what was wrong with it.
Every once in a while, actually, fairly often, I would get stuck writing these theory sections. What I was writing just didn't sound good. Invariably, after getting up from my desk and walking over to the coffee machine and thinking about the problem, I would discover that the source of my ineffective prose was a lack of understanding of how the machine worked. I was trying to explain something that I didn't understand. I discovered that if I didn't understand something, I couldn't explain it. I further discovered that this rule was pretty much true of anyone who sets out to explain something.
So the next time you read an explanation that doesn't make sense, chances are the person explaining it doesn't understand how it works. Read my next post on stability of small boats for an example of a topic that hardly anyone understands but many people feel compelled to write about all the same.
The other possibility, especially in journalism, when explanations don't make sense, chances are, somebody is lying.
Wednesday, May 7, 2008
Today's Shipwreck
Boats don't last forever. Sooner or later they die, and when they do it's often right in the water in an inconvenient place. Often someone just abandons them and they get blown into shore. At other times, someone just ties them up to a dock and leaves them to rot.
In any case, I see them often enough while paddling about that I've started taking pictures of them as a kind of recurring phenomenon that seems worth documenting.
Here's today's wreck, a plastic sailboat that blew into shore. Make up your own story about how it got there.
Monday, May 5, 2008
Thursday, May 1, 2008
May Day
My wife just informed me that today is May day. In many parts of the world, this is a holiday, kind of like Labor Day in the US. I suspect that we don't celebrate May Day in the US because of socialist overtones that the day has acquired. In any case, it is spring here in California. Currently, the locust trees are in bloom, and yesterday, the brown pelicans returned to SF Bay. Surely Summer must be near. Pictures of locusts and pelicans to follow.
A pelican fishing in the seaplane lagoon out front of the shop. They fly into the wind which is coming out of the west and when they see something in the water, they fold their wings, turn on their backs and hit the water with their beaks open. Even at a hundred yards distance when you can't hardly see the bird, you can still see the splash.
One of the locusts in bloom. We also have white ones.
A pelican fishing in the seaplane lagoon out front of the shop. They fly into the wind which is coming out of the west and when they see something in the water, they fold their wings, turn on their backs and hit the water with their beaks open. Even at a hundred yards distance when you can't hardly see the bird, you can still see the splash.
One of the locusts in bloom. We also have white ones.
How's the Book Coming, Part 2
For those of you paying attention to the title of the post, I skipped directly from part 0 to part 2. There is no part 1. The part zero comes from thermodynamics, where they elaborated the first and second laws and then some smartalek came along and elaborated an even more fundamental law and since they didn't want to renumber the other laws, they made this one the zeroth law of thermodynamics.
How's the book coming? I worked on it for a short time yesterday. What happens is that as I build boats or teach others how to build boats, a light comes on now and again and I have some insight into a better way to do something or discover what I think is a reason why something was done a certain way and then want to incorporate that into the book. And so, as one comment pointed out, the writer is under the illusion that he can never finish the book because there is always more to discover.
But regardless, I'm getting closer.
One of the problems of instructional book design is that I want to cover the construction of different models of baidarkas in this book as well as different construction techniques and am wrestling with the best way to approach this problem. For instance, you can join deck beams to the gunwales either by doweling them or by doing mortise and tenon construction. I favor doweling because it is faster and simpler. However, I do want to explain how to do mortise and tenon construction. Another instance of design variation would be the use of flat ribs vs. round ribs. My dilemma is how to best organize the information so as not to confuse the reader with a whole bunch of options.
I personally like information presented in a sequential manner and don't like having to skip around to consult appendices in other parts of the book, but to have all the options in the main flow of the book would be confusing, it seems. I think I'm talking myself into having a main flow, a recommended way of building the boat with options at the end of each chapter.
By the way, the second edition will have all the info from the first edition, but there will also be info on how to build different models of baidarkas, like the long skinny ones from Akun and a short version of my own creation, plus two seaters and so on. And there will be a lot more pictures. I want the thing to be more like a comic book with pictures leading the way.
How's the book coming? I worked on it for a short time yesterday. What happens is that as I build boats or teach others how to build boats, a light comes on now and again and I have some insight into a better way to do something or discover what I think is a reason why something was done a certain way and then want to incorporate that into the book. And so, as one comment pointed out, the writer is under the illusion that he can never finish the book because there is always more to discover.
But regardless, I'm getting closer.
One of the problems of instructional book design is that I want to cover the construction of different models of baidarkas in this book as well as different construction techniques and am wrestling with the best way to approach this problem. For instance, you can join deck beams to the gunwales either by doweling them or by doing mortise and tenon construction. I favor doweling because it is faster and simpler. However, I do want to explain how to do mortise and tenon construction. Another instance of design variation would be the use of flat ribs vs. round ribs. My dilemma is how to best organize the information so as not to confuse the reader with a whole bunch of options.
I personally like information presented in a sequential manner and don't like having to skip around to consult appendices in other parts of the book, but to have all the options in the main flow of the book would be confusing, it seems. I think I'm talking myself into having a main flow, a recommended way of building the boat with options at the end of each chapter.
By the way, the second edition will have all the info from the first edition, but there will also be info on how to build different models of baidarkas, like the long skinny ones from Akun and a short version of my own creation, plus two seaters and so on. And there will be a lot more pictures. I want the thing to be more like a comic book with pictures leading the way.
Tuesday, April 29, 2008
The Roger B. Smith Design Award Goes to ...
My Ryobi R1801M router is a piece of crap. I think the intentions of the designers were honorable, but in the interest of economy, they made the screw mechanism which you use to set the depth of the router bit out of plastic. Nothing wrong with plastic of course except that in this case, the plastic of the screw mechanism reacts with the sap in the sawdust and glues the screw mechanism shut so you can no longer adjust bit depth thereby rendering the whole router useless, unless you don't care how deep you rout something.
My solution was fairly simple. I took a Dremel tool with a cutoff bit to the router and cut through the plastic screw collar, peeled it loose from the body of the router to which it had glued itself and then was once again able to turn the screw collar and adjust router depth.
This operation had all the subtlety of a frontal lobotomy performed with a screw driver, but it was effective.
In case you're wondering who Roger B. Smith was, he was the CEO of GM for most of the 1980's. He tried to make GM profitable by cutting down on quality. Given that he was an accountant by training and not an engineer, this no doubt seemed like a reasonable approach to him. If you sell millions of cars per year and you can save a few bucks per car by cutting corners on quality, you can save yourself a few million bucks.
No doubt the good folks at Ryobi were inspired by the example of Roger B. Smith and decided to save money by using plastic for the screw mechanism instead of metal, thereby boosting the profitability of the company and the approval of Mr. Smith from beyond the grave.
..
But wait, there's more: I just went to the RYOBI web site www.ryobi.com. This site is even more lame than their power tools. On the other hand, they seem to have hired some American ad agency to sell tools to women and have this woman with the suspect name of Norma Vally who seems to be the mascot for their chixcanfix website http://www.chixcanfix.com/ Picture of Norma below - picture pulled off the website - it comes in three parts, norma_top.jpg, norma_mid and norma_bottom.jpg. Any failure of the parts to align is entirely due to limitations of the blogger software which auto-sizes all graphics.
My solution was fairly simple. I took a Dremel tool with a cutoff bit to the router and cut through the plastic screw collar, peeled it loose from the body of the router to which it had glued itself and then was once again able to turn the screw collar and adjust router depth.
This operation had all the subtlety of a frontal lobotomy performed with a screw driver, but it was effective.
In case you're wondering who Roger B. Smith was, he was the CEO of GM for most of the 1980's. He tried to make GM profitable by cutting down on quality. Given that he was an accountant by training and not an engineer, this no doubt seemed like a reasonable approach to him. If you sell millions of cars per year and you can save a few bucks per car by cutting corners on quality, you can save yourself a few million bucks.
No doubt the good folks at Ryobi were inspired by the example of Roger B. Smith and decided to save money by using plastic for the screw mechanism instead of metal, thereby boosting the profitability of the company and the approval of Mr. Smith from beyond the grave.
..
But wait, there's more: I just went to the RYOBI web site www.ryobi.com. This site is even more lame than their power tools. On the other hand, they seem to have hired some American ad agency to sell tools to women and have this woman with the suspect name of Norma Vally who seems to be the mascot for their chixcanfix website http://www.chixcanfix.com/ Picture of Norma below - picture pulled off the website - it comes in three parts, norma_top.jpg, norma_mid and norma_bottom.jpg. Any failure of the parts to align is entirely due to limitations of the blogger software which auto-sizes all graphics.
Wednesday, April 23, 2008
Pt. Hope Kayak Revisited
Two days ago the wind was blowing straight out of the west and whipping up whitecaps. So I thought it was time to give the Pt. Hope boat another try. As you may remember, its flatwater performance was unremarkable. Because the boat is short it has no glide. Because the keel line sweeps up at the stern, it does not track well. And because the bow is fairly blunt, the boat pushes a fair amount of water.
But I suspected that all these apparent faults might turn out to be virtues under the proper conditions. And in wind and short chop they were. The boat seemed to be just the right length for short steep wind waves. It rose nicely to the waves. The full bow no doubt helped as did the upswept keel line at the stern. At no point did the bow punch into an oncoming wave. By the same token, lack of glide in chop was not an issue. I don't think any kayak would have much glide in such conditions. And tracking was not an issue either. The wind and the waves were pushing the boat around to such an extent that lack of tracking wasn't noticeable.
So all in all, the boat was well behaved in rough water. I suspect that these were the conditions that it was designed for.
But I suspected that all these apparent faults might turn out to be virtues under the proper conditions. And in wind and short chop they were. The boat seemed to be just the right length for short steep wind waves. It rose nicely to the waves. The full bow no doubt helped as did the upswept keel line at the stern. At no point did the bow punch into an oncoming wave. By the same token, lack of glide in chop was not an issue. I don't think any kayak would have much glide in such conditions. And tracking was not an issue either. The wind and the waves were pushing the boat around to such an extent that lack of tracking wasn't noticeable.
So all in all, the boat was well behaved in rough water. I suspect that these were the conditions that it was designed for.
Tuesday, April 22, 2008
Almquist Lumber 2nd Annual Wooden Boat Show
I have been invited to come up to Arcata for the second annual wooden boat show put on by Almquist lumber. The date is May 17 for anyone wanting to stop by and talk skinboat. Check out the website at http://www.almquistlumber.com/boatwoods.html
While up there, I will be checking out Trinidad for suitability as a TAKS site. Then, end of June, I will be back and doing a Greenland boatbuilding course. More on that to come.
While up there, I will be checking out Trinidad for suitability as a TAKS site. Then, end of June, I will be back and doing a Greenland boatbuilding course. More on that to come.
TAKS 2008, The Blue Water Symposium
TAKS 2008 is coming up in October. For those of you who don't know what TAKS is, it's the Traditional Arctic Kayak Symposium. This year, we're looking at three possible sites for the symposium. There is of course San Simeon where we had it the last two years, but this year, we're also looking at Mendocino and Trinidad, which is north of Arcata. Mendocino is about 3.5 hours north of San Francisco. Trinidad is 6 hours north of San Francisco.
John Petersen is headed up to Mendo today, Tuesday. He's going to check it out to consider suitability for TAKS. He will also head up to Trinidad a day or so later to check it out. Stay tuned, as they say for more info.
John Petersen and furry friend on the way up to Mendocino.
I will be headed up to Arcata in May to check it out and will try to swing by Mendocino. Both are no doubt cool places.
We are also trying out slogans for TAKS. Somebody pointed out that TAKS is one of the few of these kind of events that happens on the open coast with the attendant surf and potentially rough conditions. So we're playing around with that idea - the blue water symposium.
So we still don't know where the symposium will be this year, but it will be October 3, 4 and 5.
John Petersen is headed up to Mendo today, Tuesday. He's going to check it out to consider suitability for TAKS. He will also head up to Trinidad a day or so later to check it out. Stay tuned, as they say for more info.
John Petersen and furry friend on the way up to Mendocino.We are also trying out slogans for TAKS. Somebody pointed out that TAKS is one of the few of these kind of events that happens on the open coast with the attendant surf and potentially rough conditions. So we're playing around with that idea - the blue water symposium.
So we still don't know where the symposium will be this year, but it will be October 3, 4 and 5.
Thursday, April 17, 2008
Sandbagging
See a few posts back for seaworthiness. Seaworthiness has something to do with stability and stability is aided by a low center of gravity. But heavier boats glide better as well because they have greater momentum than a lighter boat at the same speed. So we're hoping that you can make your kayak heavier and therefore more seaworthy. The Aleuts reportedly carried ballast in their kayaks, ballast equaling roughly the weight of their kayaks. So today I went out in my Aleut kayak and brought along one of those three sandbags pictured above. These guys weigh about 35 pound apiece. The idea was to place a sandbag in back of the cockpit to see how that would affect handling of the kayak. First of all, 35 pounds is fairly heavy and hard to push around in a boat with ribs. 15 pound sand bags might be a better choice. Not only is 35 pounds heavy, but it's also too big and hard to get into a tight boat.
But on to the effect of 35 pounds on handling. As expected, a heavier boat is harder to accelerate. I was expecting the effect to be negligible, but instead, it was noticable. Glide improves, I suppose but paddling definitely takes more effort with a heavier boat. I had been hoping that the extra weight would affect mostly acceleration, but it affects cruising at constant speed as well. I suppose. Wetted surface increases as does the amount of water that needs to be pushed out of the way by a heavier boat. All in all, extra ballast on flat water is mostly an annoyance. Whatever is gained isn't worth the extra effort.
But I'm still holding out for improved performance in rough water. I'll have to give the sandbags another try next time the wind blows.
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