I understand that a narrow paddling station means you don’t have to reach out as far to plant your paddle. But aren’t you supposed to use a vertical paddle stroke for the most frequently used forward stroke, which would mean you have to reach out as far as the widest part of the boat anyway?
What am I missing?
Good question!
I have wondered about this too, and I think the assumption about the vertical forward stroke is the problem here. It is considered important to have the paddle blade in the water as close to the hull as is possible with a forward stroke. The wider the paddle station is, the more vertical the forward stroke should be then, otherwise one needs more correction with the forward stroke to go straight when paddling as a stern or solo paddler. With tumblehome in a relatively wide paddle station the need for a vertical forward stroke is a bit less, hence a bit easier paddling and one could perhaps use a bit longer paddle more easily too.
ADDIT:
pblanc will answer this - in fact he did on the cboats forum…
"Shouldered tumblehome, in which the hull flares out to a “shoulder” of maximum beam a few inches below the sheer line and then sharply recurves in to the gunwales, offers the advantages of a flared hull in that it sheds water well and has good secondary stability, but reduces the width at the gunwales. Since you often have the boat heeled a bit toward the side your paddle is on, the outside edge of the outwale often winds up directly above the maximum beam at the shoulder allowing your paddle stroke to be quite vertical yet still close to the hull.
Smoothly curved tumblehome as is found on a lot of Wenonah flat water boats tends to have a maximum beam just above the water line. That is OK for a flat water boat, but when you heel a hull like that and go past the point of maximum beam, the secondary stability disappears rather abruptly."
I am not an expert, but there is something else. If you have a flared hull with shouldered tumblehome (like a lot of David Yost designs) then the widest part of the boat is below the gunwales. So, you will feel a lot of push back (secondary stability) BEFORE you reach the open end of the boat and fill up with water. Supposedly it also sheds more splashes away from the opening than a straight flared boat, but that is beyond my understanding.
Was tumblehome designed for a more vertical shaft? Don’t know. Yes, you still want a vertical shaft and you have to reach our as far as the widest point of the boat. But I think it is more of a psychological thing that there is a gap where your knuckles should go on tumblehome hulls. You still have to reach out with the top (grip) hand if you want a vertical shaft.
@timburris said:
[…] Yes, you still want a vertical shaft and you have to reach our as far as the widest point of the boat. […]
again the assumption that you want to have a vertical shaft with the forward stroke is the culprit here: look for example at the way Flatwater Sprint Kayaks and Marathon canoes are paddled.
It all depends on the width of a canoe. With tumblehome in a wide canoe the need for a real vertical forward stroke is (a bit) less.
One must also consider the thickness of the outwales which typically adds an inch or more to the width of each side of a flared or straight-sided molded hull. As Erik pointed out, even a pretty mild degree of heel will get the outwale of a flared or straight-sided hull in your way very quickly.
Narrowing the gunwale width of the hull by even an inch makes cross strokes much easier. It also makes the switches much easier for those who paddle sit and switch.
Because even with shouldered tumblehome a boat can be too wide for a particular paddler, solos in particular are sized to the height of the paddler ( making the assumption that taller people have longer arms). A vertical stroke is important for any paddling position… Particularly critical for stern paddlers who tend to follow the gunwale and make too long a stroke… Both lead to an unwanted sweep component. If it is there you have to work harder ( J stroke or the like ) to compensate.
To bring marathon racing canoes and flatwater sprint kayaks in to the discussion introduces another design element… And muddies the picture… We’re talking recreational canoes; not ones designed for one special task…
@kayamedic said:
Because even with shouldered tumblehome a boat can be too wide for a particular paddler, solos in particular are sized to the height of the paddler ( making the assumption that taller people have longer arms).
A good solo design is sized tot the total weight of cargo and paddler and the paddlers power, perhaps shoulder width will be part of that equation, but paddler/arm length hardly so.
A vertical stroke is important for any paddling position…
Well that is the assumption that is flawed, as I tried to explain.
@canonymous said:
perhaps shoulder width will be part of that equation, but paddler/arm length hardly so.
Sure arm length matters for getting the top hand outside the gunwale. Longer arms make it easier, shorter arms make it harder, all other body measurements remaining the same. Longer arms would sure help this short paddler.
One benefit of tumblehome for me is that the lower hand can often be below the gunwale without banging it on the gunwale or hull, which makes it more comfortable to attain a near vertical stroke with the blade as close to the center line of the boat as reasonable.
I greatly prefer solo canoes with tumblehome for my paddling and my current fleet reflects that.
@Yanoer said:
@canonymous said:
A good solo design is sized tot the total weight of cargo and paddler and the paddlers power, perhaps shoulder width will be part of that equation, but paddler/arm length hardly so.
Sure arm length matters for getting the top hand outside the gunwale. Longer arms make it easier, shorter arms make it harder, all other body measurements remaining the same. Longer arms would sure help this short paddler.
Possibly, but are you paddling a canoe that was designed for a short paddler with long arms?
@Yanoer said:
One benefit of tumblehome for me is that the lower hand can often be below the gunwale without banging it on the gunwale or hull, which makes it more comfortable to attain a near vertical stroke with the blade as close to the center line of the boat as reasonable.
That can indeed be an advantage of tumblehome.
Well, I will agree that the majority of marathon canoe racers do not maintain anything close to a vertical paddle shaft. But I also agree that arm length and torso length makes a significant difference. I find longer arms/torso to be of particular advantage for cross strokes.
For paddling with a considerably less than vertical paddle shaft, as is common in marathon racing, pinched gunwales are an obvious advantage.
@canonymous said:
@Yanoer said:
@canonymous said:
A good solo design is sized tot the total weight of cargo and paddler and the paddlers power, perhaps shoulder width will be part of that equation, but paddler/arm length hardly so.
Sure arm length matters for getting the top hand outside the gunwale. Longer arms make it easier, shorter arms make it harder, all other body measurements remaining the same. Longer arms would sure help this short paddler.Possibly, but are you paddling a canoe that was designed for a short paddler with long arms?
My solo canoes are about as good as it gets - size wise - for smaller paddlers who don’t trip.
@canonymous said:
@timburris said:
[…] Yes, you still want a vertical shaft and you have to reach our as far as the widest point of the boat. […]again the assumption that you want to have a vertical shaft with the forward stroke is the culprit here: look for example at the way Flatwater Sprint Kayaks and Marathon canoes are paddled.
It all depends on the width of a canoe. With tumblehome in a wide canoe the need for a real vertical forward stroke is (a bit) less.
All anyone has to do to see the flaw in this argument is to employ a truly vertical paddle stroke long enough to see the difference. The fact is that a wider canoe needs a vertical forward stroke all the more, and the more vertical the stroke, the less correction needed. The fact that few of us (including racers) actually demonstrate a truly vertical stroke much of the time does not negate this reality. You can deny physics, but you can’t avoid the mechanical reality.
Whether tumblehome is intended to or succeeds to aid a vertical paddle stroke is a separate issue. Besides all that, not all strokes are uncorrected forward strokes (obviously), and tumblehome aids in other ways. One might also ask - other than degree, how is tumblehome any different from a kayak hull? No need to answer that here - it’s a rhetorical question for you to ponder on.
“The fact that few of us (including racers) actually demonstrate a truly vertical stroke much of the time does not negate this reality. You can deny physics, but you can’t avoid the mechanical reality.”
That really sums up the situation well. Related to that, I find that there are times when it’s beneficial to make the stroke “beyond vertical” so that the blade actually does its work closer to the centerline than even a vertical stroke would allow. Heeling the boat toward the paddle side and reaching beyond vertical with the upper hand accomplishes even more, attacking the problem from both sides, this time moving the blade closer to the centerline and also moving the functional centerline closer to the blade. In either case, I don’t do it for more than two or three strokes in a row, and wouldn’t really recommend it either, but it’s a trick that lets you apply a lot of extra power with less correction, so it clearly illustrates the point that Steve was making.
@pblanc said:
One must also consider the thickness of the outwales which typically adds an inch or more to the width of each side of a flared or straight-sided molded hull.
I think that actually makes a lot of sense. The outwales on my tandem canoe stick out almost as far as the widest part of the boat, so compared to a straight side hull, the tumblehome does compensate for the gunwale width and allows for the paddle to be close to the hull, while at the same time providing a channel for the shaft hand to travel.
As Erik pointed out, even a pretty mild degree of heel will get the outwale of a flared or straight-sided hull in your way very quickly.
I see that, although I try to not heel during forward travel in the tandem.
Narrowing the gunwale width of the hull by even an inch makes cross strokes much easier. It also makes the switches much easier for those who paddle sit and switch.
Do you often see cross strokes and tumblehome together?
@melenas said:
@anon64780766 said:
As Erik pointed out, even a pretty mild degree of heel will get the outwale of a flared or straight-sided hull in your way very quickly.
I see that, although I try to not heel during forward travel in the tandem.
When paddling in a solo canoe, I try to avoid an onside heel, because that can give a canoe a tendency to turn to your off-side, with the result that you need even stronger correction strokes to go straight.
With a little (off-side) heel the outwale of my flared canoes do not get really in my way any more then usual, perhaps even less so. Rotating the canoe in my drawings also doesn’t indicate something like that.
But the next time when I am in my canoe I will pay more close attention to that and come back at it.
Stay tuned
Next episode:
just returned from a quick paddle, and couldn’t detect a significant difference when heeling to the left or right in my Swift Osprey. This design has the so called “shouldered tumblehome”, but I don’t think that my flared MRC Pearl would be different, although this is a very narrow canoe design.
Of course your paddling may vary, depending on the actual paddling style used: I didn’t try a longer paddle with a wider hand spacing, because I don’t like to paddle that way in relatively wide solo canoe.
@melenas said:
@pblanc said:
One must also consider the thickness of the outwales which typically adds an inch or more to the width of each side of a flared or straight-sided molded hull.I think that actually makes a lot of sense. The outwales on my tandem canoe stick out almost as far as the widest part of the boat, so compared to a straight side hull, the tumblehome does compensate for the gunwale width and allows for the paddle to be close to the hull, while at the same time providing a channel for the shaft hand to travel.
As Erik pointed out, even a pretty mild degree of heel will get the outwale of a flared or straight-sided hull in your way very quickly.
I see that, although I try to not heel during forward travel in the tandem.
Narrowing the gunwale width of the hull by even an inch makes cross strokes much easier. It also makes the switches much easier for those who paddle sit and switch.
Do you often see cross strokes and tumblehome together?
The David Yost designed “Fire” boats (Flashfire, Wildfire, Starfire) have shouldered tumblehome and have been among the most popular canoes for freestyle paddlers. Freestyle uses cross strokes all the time.
Whether a boat turns off-side or on-side in response to a heel to one side depends a lot on hull design. While it is true that a longer, relatively straight-keeled hull with a sharp water entry will usually turn away from the side it is heeled to, on on-side heel can often be used in solos to reduce the number of correction strokes required to maintain a straight course, or reduce the frequency of switches required for those who paddle hit and switch.
This technique has been known for a long time and has been called “paddling an inside circle” by Tom Foster and Charlie Wilson. This method has been rechristened the “2x4” method by Andrew Westwood and has virtually replaced traditional technique for whitewater open boaters paddling the new, short boats. The “cab forward” technique requires keeping body weight balanced forward, keeping strokes short and well forward, utilizing the tendency of the unweighted stern of the canoe to skid and the tendency of a bow wave that builds up on the off-side of a moving boat to resist a turn to the off-side. Instead of going absolutely straight, the boat is paddled in arcs of a circle of various radii and it is possible to go very nearly straight with no correction whatsoever using only forward and cross-forward strokes, or using only forward strokes with occasional switches. This short, somewhat cute video demonstrates the idea. The actual on-water demonstration begins around the 4:20 minute mark:
http://www.youtube.com/watch?v=xrWYLTEWkyw
The paddler here is mostly carving fairly tight on-side and off-side circles and figure of eights but it is possible to open up the radius of the circle to very nearly approximate a straight-line path.
While this technique is especially applicable to short, highly-rockered hulls with a sharp chine, it will work even with much longer, less rockered hulls with a shallow arch cross-sectional contour.
@pblanc said:
Whether a boat turns off-side or on-side in response to a heel to one side depends a lot on hull design. While it is true that a longer, relatively straight-keeled hull with a sharp water entry will usually turn away from the side it is heeled to, on on-side heel can often be used in solos to reduce the number of correction strokes required to maintain a straight course, or reduce the frequency of switches required for those who paddle hit and switch.
The effect you get when you heel your canoe, depends on:
Most touring canoes will turn to their off-side with some onside heel when paddled straight forward.
Some designs (e.g. hard chined hulls with very deep V-bottoms?) may do this the opposite way, but these are not the hull shapes one is likely to find in the regular touring canoe – at least I don’t know one.
From the Osprey I happen to know that this canoe was designed with the idea that it would be paddled with a little on-side heel. And indeed it is designed to be quite neutral then – only at high speeds there might be a little turning effect to the off-side. Nevertheless when paddling sitting, I still paddle this canoe with a little off-side heel unless there is a strong on-side cross-wind that causes weathervaning. But in that situation I do not need correction strokes anymore to go straight. When kneeling I always have some onside heel, because it is too difficult for me to avoid it. But then I cannot paddle as fast anyway, so I only kneel when I have to, that is when paddling in substantial waves.
@canonymous said:
@melenas said:@anon64780766 said:
As Erik pointed out, even a pretty mild degree of heel will get the outwale of a flared or straight-sided hull in your way very quickly.
I see that, although I try to not heel during forward travel in the tandem.
When paddling in a solo canoe, I try to avoid an onside heel, because that can give a canoe a tendency to turn to your off-side, with the result that you need even stronger correction strokes to go straight.
With a little (off-side) heel the outwale of my flared canoes do not get really in my way any more then usual, perhaps even less so. Rotating the canoe in my drawings also doesn’t indicate something like that.
But the next time when I am in my canoe I will pay more close attention to that and come back at it.
Stay tuned
Next episode:
just returned from a quick paddle, and couldn’t detect a significant difference when heeling to the left or right in my Swift Osprey. This design has the so called “shouldered tumblehome”, but I don’t think that my flared MRC Pearl would be different, although this is a very narrow canoe design.
Of course your paddling may vary, depending on the actual paddling style used: I didn’t try a longer paddle with a wider hand spacing, because I don’t like to paddle that way in relatively wide solo canoe.
Curious that your drawing here shows a nearly vertical paddle…
In the Sojourn, offside heal helps. A vertical paddle also helps. In the Guide, onside heal helps (inside circle, as Pblanc describes). A vertical paddle also helps. Solo in the tandems, offside heal ain’t happening when paddling. Guess what though - when poling, an offside heal can help…and vertical pole (relative to canoe viewed from stem) also helps.
I think I see a pattern.
