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Blade Size
Some mostly very excellent replies already, but I know you are angling
for an essay from me (I could just e-mail it I suppose...). I can't recall seeing any wrong answers in there, basically smaller paddles will slip at a much lower "pull" then large blades. If the paddle slips in the water, you will be pulling it towards you rather than you past it, therefore a bigger blade is going to get you moving faster. This slippage does however form a sort of safety valve. If you are sea paddling all day you don't want a paddle that can absorb a huge amount of power each stroke because it will tire you quickly, and you are probably right about the injury thing - overworking could leave you vulnerable to muscle injury. That's why Peter uses Archipelagos and I use Kinetic touring blades on the sea, but both carry "bigger brother" blades both as spares and as alternatives in case of waking up and finding 2' of surf dumping on the launch spot or something A lot of people just use Nordkapps but they always look more shattered after a long day! I have tried my Kinetic XTis back to back with the touring version and they do put more strain on even over a short distance. But I know you are mostly a river runner! In river running terms a bigger blade makes sense because when you need a lot of power, you usually need it very quickly. But some blades out there designed for slalom and/or white water racing really are a bit more powerful than you would normally need. To be honest the Kinetic XTi is probably more powerful than I really need, but I have the shoulders to cope and my river technique involves a lot of drifting when possible. Playboating blades are a bit of a mixed bag. Many really are incredibly powerful, some powerful on the back as well as the face - the reason being that it takes quite a lot of power to lift half of the boat and paddler out of the water as so many moves require. Lendal are doing a blade called the mystik which is designed for playboating/surf, and which they indicate is probably too small for river running - but myself and Mark W are experimenting with using these as river blades (in the lightweight carbon composite construction), and whilst it's been fairly crappy and dry until recently I have been reasonably impressed with them so far (mine are on a fixed cranked shaft and are lighter than most other manufacturers lightweights). Now for the complex part - why some blades or more efficient or more effective than others and how size isn't everything! Your regular symmetric blade works by drag alone, but some of the water spills around the edges and forms eddies or vortices. These vortices required energy to start and the robbed it from what you exerted on the paddle, so a blade that is designed to work in a way that creates less eddies can turn more of your input power into moving forward. This doesn't mean that an efficient blade is more tiring - you are getting more forwards motion out of the same input. Some ways of making blades more efficient include altering the edge that enters the water first (make them asymmetric) changing the curvature of the face and the chord of the foil section. I guess the ultimate expression of this would be wing paddles although these require a quite different style of paddling to make the most of them. Someone suggested that your build is a factor - I would agree! And I would have to say that you are a fairly average build (although probably more powerful than average) so a mid sized paddle (standard werners, mystik, etc.) would probably suit you well but you could probably use a larger blade like a kinetic XTi or something without any problems. Basically just a new regular blade will probably be perfect for you! Here is a test I devised whilst struggling to steer my playboat successfully down the Etive using my 4 year old (at the time) werners which I still use on rocky runs like that. Paddle along and try and sweep the bow up on the move - not like a cartwheel, just a few inches like boofing a drop or something. Then swap paddles with someone with new blades (or the ones you've got on demo) and try the same thing again. If you find that the bow lifts a lot further with the new paddles, you probably need new ones! I did this after a really frustrating day when I'd buried the bow on every little drop of 4" or more and failed to dodge around loads of rocks and stuff. My bow hardly lifted at all with my werners, but with Jens new but otherwise identical paddle I was able to lift it 6" with hardly any effort. I then went one stage further and tried to flatwheel, not a problem with my paddle as it was impossible to throw the bow down properly, but with Jens I was able to smash my bow right down onto the riverbed as I usually do with my kinetics. At this point myself and Neil had old werners that had started out as 198's - mine measured 194 and his were 190 (or less). We had just been using them and hadn't really noticed the performance drop off (just thought we were paddling worse than normal) until we tried new paddles back to back - the difference really is astonishing! People have mentioned stroke rate and hinted at the importance of inertia through the air, or lack of it. I think Roo will have decided on his ideal shaft length by now based on the ratio of playing to river running that he does (is sprinting more important than momentum?) so I would just like to add that in my opinion lightweight paddles are far superior because they travel through the air more easily which allows higher stroke rates and more importantly makes it easier to vary stroke rate and of course absorbs less of your energy over the length of the paddling day. Some people find them hard to get the hang of because the lack of inertia feels different, but once you get the hang of them it is impossible to go back to normal weight paddles (Unfortunately my travel paddles are kinetic splits so I have to from time to time!). As for your particular situation, I'm guessing you have plenty of sea paddling available where you live now - I reckon you should consider a set up like Marks - 4-way paddlok split carbon composite Mystik paddles with a short HPS shaft for river running and a longer G1F shaft (possibly cranked) for sea paddling. Of course you could add bigger or smaller blades to that setup at a later date if required. Lendal do have a distributor in NZ so you should be able to get hold of them. So, anything I've left unclear? I can write another essay tomorrow if you want JIM roo wrote: Hi All I did a quick archive search but found nothing too useful. If anyone could point me in the right direction that would be great..... I've been getting a lot of comments recently about the size of my paddle blades. They've been ground down considerably since 1998 and instead of a symmetric blade shape they are now very similar to a shrunk kinetic shape. (This is only because I use my paddles the same way round all the time. They were any orientation paddles, but luckily I kept using them the same way and avoided ending up with very expensive cocktail sticks!) So enlighten me to the pros and cons of different blade sizes..... I assume it's a relative assessment, but... Large blades provide more power, but give a higher chance of injury? Small blades allow/require a higher stroke rate for equivalent large blade propulsion? Is the size irrelevant, because all that is required is enough friction to plant the blade and pull yourself past the shaft? Should I buy some new paddles with normal sized blades? I await your informed replies. hf roo |
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