Letstry to keep this one on topic and try to get to the bottom of of the advantage ( if any )of chines on OC1 s and OC2s. In the other thread the chine issue wasnt thoroughly explored. Maybe there`s no data to turn to on the subject as it pertains to outrigger canoes , who knows. I think though that outrigger canoes are not simply displacement hulls .
At some particular speed they begin to lift and displace water differently than they do at lower speeds. Some paddler said that since sprint kayaks dont have chines then maybe outriggers dont require them either for maximum speed. Theres` a big difference between sprint kayaking and downwind surfing on a canoe. I could be wrong but , I think a canoe going downhill on a wave , downwind can make better speed than a sprint kayaker .
Any experts out there?
Submitted by fuzerider on Tue, 01/08/2008 - 12:45pm
My dad made a ocean going canoe that is renowned as the fastest of it’s type of canoe that has been made . And he made grooves all through the canoe. Or chines . That at first glance looks like corrugated fibreglass sundeck roofing . And when I asked him if smooth would be faster he said( the air in the water goes through the channels and lifts the canoe and makes it faster) and it works . Many have tried to make better but failed, me included. another thing my dad said that went zooming over my head was (its moor important how a canoe leaves the water than how it enters it.) when I have spare time I will sit and ponder that one and still get nothing. Here is a pic, of his masterpiece
a href="http://s291.photobucket.com/albums/ll314/Mulus/?action=view¤t=i24542209_40228_3.jpg" target="_blank">
#71 Sat, 04/05/2008 - 6:58am
I've heard/read that it's best not to wax below waterline because it's slower. However another source said to use 303 protectant below waterline. I use 303 for my hulls but it's more to do with UV protection out of water than trying to go faster in water.
Funny, you'd think a waxed surface that beads water is faster below waterline but I believe it has to do with laminar flow, blah, blah, blah, that I can only answer adequately after lots of reading, which I soon forget because between all the armchair talk about boats I like to just paddle and dig being on the water.
#72 Sat, 04/05/2008 - 7:15am
You would want to make it fish friendly whatever you use. I heard once egg yoke the night before work and that would be feeding the fish as well.
#73 Sat, 04/05/2008 - 7:27am
EZ one to remember.
Form. Fair
Surface. Smooth
Of less importance to some.
Without Wax ?
Polish. Protect
#74 Sat, 04/05/2008 - 12:01pm
Shark skin makes super small turbulences and thins out the boundary layer . Riblet type coating has been used in racing sailboats before but was banned in 1989 as it was very expensive to do and not availibile to most people.
Smooth surfaces are actualy not the fastest thing around ,tank testing has proven that besides varius special coatings that mimic the sharkskin effect the fastest thing is having the surface sanded with 1200grit paper longitudinaly . It creates less drag than miror finished polished surface.
As for chines they don't do much good in canoes till very high surfing speeds,and even then as they are quite blunt they shouldnt be to effective but the negative efect is also quite small so to most paddlers they dont make a differnce.
In boating the chines are used for couple of functions ,one is to provide lift to planning craft ,second enable clean water break(water tends to hug round shapes) for less drag,some are there just for manufacturing reasons etc. But all this thing work nicely in a powerboats or a fast sailboats which both have power to spare to overcome their negative efects .Bur canoes have no power to spare(unless riding on force of gravity down hill)
#75 Sat, 04/05/2008 - 12:56pm
Thanks Canoemaker, that helps me understand chines a bit better. Trying to figure anything out by reading the past posts only makes it more confusing in the long run, and any article written by scientist/engineer is usually directed at their peers and I have to jump pretty high to keep it from going over my head. But the articles aren't so bad if you are an insomniac...and you need something to make you sleepy.
back to shark coating. I also read somewhere that the bumpyness of the skin also makes it almost impossible for microscopic critters to attach to it i.e. no barnacles on a shark. A sharks skin is self cleaning at certain speeds leaving it to be more efficient up to 10%. So i guess it makes sense for maybe an 0C-6 as it is larger much heavier canoe to try a shark coating. As we can take in account of the weight addition and just make a slightly lighter canoe to forgive the added weight (and still have it fit the minimum weight requirements). I am assuming that the actually coating is not extremely additive in weight...though. Adding it to an OC-1 don't make sense as I think we are at the lightest that we can make are canoes already and an added weight difference can't be subtracted from the canoe without affecting structural integrity. That is of course unless they invent some super carbon fiber weave that minimics sharksin riblets, golfball dimples that an epoxy won't fill in.
Mulus.....is that the Suquamish canoe that your dad built? It's got a nice adzed finish to it. I've seen it and touched it (can't remember who owns the canoe though) and it's a nice canoe. I've heard that an adzed finished canoe will be faster than a smooth surface dugout. I always thought that it was like having a golf ball surface....but old posts on hull surfaces and a conversation with a engineer/boatbuilder say that we can't attain enough speed for it to be more efficient. Who knows? Love that canoe though have you seen the canoes that Tony Johnson helped design using tape and seam method. The perform outstandingly....I have a older version of a tape seam westcoast canoe that didn't have the benefit of Tony's knowledge and it is much tippier....we are faster off the line...but nervous as heck paddling it at speed in rough water. Tony's is much more forgiving...bumpy to big water and the top speeds are about the same. I guess similiar to a hurricane....vs. Zephyr, fuse, .....fill in blank. Amazing what a few changes can do for performance.
Sorry that I've digressed this post from chines to sharkin..to golfball dimples to hurricane vs.....
I'll change my handle to the "Sidetracker" from now on.
#76 Sun, 04/06/2008 - 12:47am
Was just reading marzanboats.com description of their kit OC-1. "smooth chineless hull giving you effortless speed". What more needs to be said?
#77 Sun, 04/06/2008 - 6:22am
Sloughcanoe, the Big canoe is owned by Squamish nation.
Who known’s what makes it so fast for the type of canoe it is. The question is what makes the Hurricane fast or any canoe fast? the shape? If I could find out I would make allot of canoes with that stuff. Maybe the shaping
#78 Sun, 04/06/2008 - 6:41am
If you don't feel like sanding your one-man's hull with FINE (1200's good) grit, then just make sure it's clean. A completely smooth, (chined or not) hull is fastest when it's totally clean, and free of any contaminants. Just use cheap dish-soap - not the kind with added lotions/oils to keep your hands soft. Don't bother waxing... unless you happen to be racing against me, then you can wax all you want.
A longitudinally wet-sanded hull is fastest, but at the speeds we're talking, by only a small percentage. And once you sand it, you need to clean it ALL THE TIME.
...laminar flow, blah, blah, blah...
#79 Sun, 04/06/2008 - 8:00am
If those "corrugations" start to get too big, all you do is add wetted-surface...
...which slows you down.
#80 Sun, 04/06/2008 - 8:03am
And when we are at it the currugations or riblets are only of any use in last 1/3 of a canoe and gain is superminimal .Its a differnt story in swimsiuts where wake and turbulence are reduced considerably but that is due to swimer making so many compared to a canoe.
And when we are at it the nature already has beter solutions for the problem you know evolution and survival of the fittest dont leave room for 2nd place.
The bigest gain in nautical world that we are still waiting for it to be achieved is by pressure sensitive skin like on a dolphin ,the pressure along any object in water is changing all the time and fleksible skin compensates for that by small variations of the shape which cancel out small changes in pressure and there by keeping the water flow realy laminar as long as posibile. But nano tech in coatings is coming fast and all these thing are bound to be developed
#81 Sun, 04/06/2008 - 11:31am
Yep, wetsand and don't buff after and you sort of 'open the grain' so to speak ... the boats suck everything up in the water only way to clean is to scrub / wetsand again ... or acid wash if the boat has been stored for a long time stained.
No really the same but if you ever paddled a skin covered boat, one can get the sensation of what canoemaker is talking about. Not so much for speed as a feel as if you are working with the water on a more organic and yielding level ... quiet too.
#82 Sun, 04/06/2008 - 12:23pm