@willowleaf said:
Somebody on another paddler forum posted a 26 ounce Werner carbon Kalliste paddle for sale for $320 and somebody else posted the comment that āyou can get a carbon paddle from Academy Sports for $99ā.
Out of curiosity I looked at the Academy website and they do have a ācarbonā paddle by Magellan for $149. It weighs 50 ounces!! 50 ounces is almost a pound heavier than most ābarbellā aluminum and plastic tourist rental paddles! Also, half the buyers who reviewed the model reported that the shaft broke early on during use. Such a bargain!
I pointed out that using a 50 ounce paddle rather than a 26 ounce paddle would mean that you were swinging almost 1.5 extra tons of weight per hour.
30 strokes per minute x 60 minutes = 1800 strokes x 24 ounces = 43,200 ounces divided by 16 oz/pd = 2,700 pounds.
Second commenter said āI donāt think your physics/mathematics make senseā. Numbers donāt lie. Engineers, weigh in.
Well if youāre going to throw out nerd bait youāll catch me almost every time.
I think your analysis is fine as a first approximation (especially since you have stated your assumptions) and interestingly enough this site has an example that follows your logic exactly.
But there are some detailsā¦
You donāt really lift the whole paddle each stroke, it seems more like you lift one side. The motion is pretty complex but I think kayak paddles sort of pivot around the center. So maybe you āliftā only half the paddleā¦so this would reduce your estimate.
There are dynamic forces involvedā¦since you have to accelerate and decelerate the paddle. Those forces increase with weight and would add to your estimate.
Thereās some effect of mass distributionā¦even intuitively if you add 20 ounces to the center of a kayak paddle shaft it would be easier to use than if you added 10 ounces to the tip of each blade. I suspect that a 50 ounce kayak paddle would have heavy blades and this would add to the overall effort (since the cg of each half of the paddle would move closer to the blade).
I found a tennis racket swing weight estimator that seems to highlight the four key factors.
http://twu.tennis-warehouse.com/learning_center/swingweight_calc.php
And oh my goodness we havenāt even touched on wind resistance. (nerd humor).
On the subjective side I can tell you that if you do sit and switch with a canoe paddle and double the weight of the paddle it takes a sh!tload more work.
Make sense?