leong

Thanks, David. Good idea. I'd first call QCC (the boat's manufacturer) to get more information about the nut size (not for the squirrel), type and what's down there. So far the stern eye is just wiggling very slightly and I don't use it to carry the boat.

-Leon

The stern eye that the stern toggle is attached to is starting to wiggle. It’s almost 5 feet from the back of the stern hatch cover so can’t reach under to tighten it. The only solution I can think of is to train a squirrel to use a ratchet wrench.

Any ideas out there?

-Leon

On 2/21/2017 at 10:08 PM, dcycleman said:

Is it difficult to fish out of your sea kayak? how is it reeling in something big ?

 

The hardest part of landing a big fish is when it's at a right angle beside the boat. I have to lean in the opposite direction to counter the fighting weight. I've capsized a few times and rolled up but ruined a couple of reels. Here are a few pictures.

Striper

Bluefish

Bluefish

Barracuda in Florida (I had to tow the fish to the nearest dock to have it gaffed)

4 hours ago, dcycleman said:

 

Hi, In the spring and summer I fish from a sea kayak usually out of Lanes (bluefish and stripers). I'm now kayak fishing in south Florida (barracuda, tarpon, jacks, etc). I don't bait fish ... I only troll using lures (mostly spoons and sluggos).

-Leon

Today I paddled to Mar-a-Lago to meet Japanese Prime Minister Shinzo Abe. I was hoping to demonstrate bracing and rolling to Shinzo and his lovely wife. I usually make the Mar-a-Lago trip alongside the ocean beaches of Palm Beach Barrier Island, but today I took the inside route (between Palm Beach and the mainland) because of the strong winds.

This is a pix of Trump Plaza as I passed by it in West Palm Beach.

Here are a couple of pix of the stinkpots I passed. Some people are really into conspicuous consumption.

Here’s a pix of Mar-a-Lago from about two miles away.

As I headed towards shore this Coastie came out to greet me.

He was unaware that I was on the way to meet the Japanese Prime Minister. He said I have two choices: 1. Stay far from shore or 2. He’ll try out his bow-mounted machine gun. I chose no. 1. However, there’s a beach on Southern Blvd. that connects the Mainland to Palm Beach and he said it was okay to paddle there. So I did.

Here are a few pix of Mar-a-Lago taken near the beach on Southern Blvd.

I had a super fast paddle home (wind and tide pushing me) averaged 6 knots over the 8 nautical miles.

At the end of the trip I parked my kayak along side of my Sunfish.

Oh, did I mention that I never met the Prime Minister.

13 hours ago, prudenceb said:

 My brain almost exploded last year when Bob Levine and Kevin Beckwith were simultaneously trying to get me to explain vectors. 

Pru,

A vector is a fancy dancy name for a line segment with a little arrowhead on one end. The rest is just commentary. Look here for a little more information. Luckily you won’t need tensors (they will really blow up your brain). Unless, of course, you want to blow up Kevin's brain.

-Leon

http://www.dummies.com/education/science/physics/what-is-a-vector/

Excellent report as usual, Pru. BTW, it’s State Stage Fort Park.

Rob and all,

Just to remind you that the trip between Good Harbor and the end of Dog Bar is usually the roughest section of the circumnavigation around Cape Ann. But more important is that there are no takeouts (except, sometimes, at Braces Cove when there are no breakers). And, Joe, the area along Bass Rocks is very rocky and this portion of the whole circumnav is arguable the most scenic part.

-Leon (who’s done the circumnav about a hundred times and is trolling NSPN from the Palm Beaches)

14 hours ago, Brian Nystrom said:

I see two issues with your examples. First 2 square feet is a low estimate of frontal area given that your chest alone is at least 1 square foot. Second, your 4 knots SOG results in extremely high hull drag when going against the2 knot current. Most sea kayaks hit their max hull speed well below that and cannot be paddled at 6 knots by a normal human being. Run the test again at a more realistic speed and the results will be much closer.

Brian and Phil,

I used 2 square feet because I used a large coefficient of drag. The extremely high hull speed (as you say) is not that high. I get my QCC700X to 6 knots (in still air and water) for short sprints. Max hull speed is just a number, not a hard speed limit. The Blackburn Challenge course is almost exactly 18 Nautical miles. The winning Epic 18’s and similar kayaks finish the course in 3 hours, or so. That’s an average speed of 6 knots for a long course. But so-called “max hull speed” of these kayaks is about 5.6 knots (1.34 time the square root of the water-line length of ~ 17.5’)

But let all this go. Nothing good on TV so, instead of rerunning the test, I decided to prove my result analytically so there can be no questions on the values that I used (it’s good that I’m retired ). I also gave it a whirl on the water but couldn’t get the proper conditions today.

See attached Mathcad worksheet for my analysis. Mathcad - DownCurrent-UpWind and vice a versa.pdf

-Leon

2 hours ago, Phil Allen said:

Leon

I still need to think more about your details, but I'm suspicious of your 9 knots of wind in the face being equal to 2knots of contrary current.  Practical experience and numerous publications would suggest that it would take close to 20-25 knots of wind to get a 2knot boat drift.

Happy holidays!

Phil

 

Phil,

There is a lot of uncertainty in the necessary wind speed because of what to use for the frontal area in the air drag formula. I used a 2 square-foot area for the paddler and kayak. At 9 knots, the wind pressure is ½ pound per square-foot. So the force of the wind is 1 pound and, according to KAPER, that’s the total drag on a kayak going at 2 knots. But let that go.

Suppose it does takes about a 20-knot wind to overcome the 2-knot current. Then, for case # 1, the drag increases to about 6 pounds and for case # 2, the drag decreases to about 9.5 pounds. So the qualitative result is the same; i.e. it’s still easier to paddle downcurrent/upwind than vice versa.

In my experience in the inlet, it does seem like a 10-knot or so wind is enough to overcome the current. But, I don’t know the exact current speed or wind speed opposite to the current. Also, I don’t account for wind generated waves on the surface that might be moving opposite to the current flow.

I think a key point is that a change in current speed costs a paddler more than the same change in relative wind speed. 

-Leon

On 12/19/2016 at 6:52 AM, Brian Nystrom said:

Since both wind resistance and hull drag are exponential functions, there's going to be little or no difference initially. Going against the current, you will approach your hull speed limit quicker, so it will become harder, sooner. Going with the current, you'll reach a higher "ground speed" before you hit the hull speed limit.

Brian,

You might want to change your answer based on the following hints:

A wind speed of approximately 9 knots against a kayaker has a force of roughly 1 pound and that cancels the 1 pound water drag on a kayak in a 2-knot current in the opposite direction.

Case 1: Say you paddle with the current (against the wind) with a speed over ground (SOG) of 4 knots. Then the relative water speed is 2 knots; (4 -2). Also, the relative air speed is 13 knots (9 + 4). Again, at a relative water speed of 2 knots the water drag is 1.00 pounds. Also, the air drag at 13 knots is 2.29 pounds. Thus the total drag you have to overcome is 3.29 pounds (1 + 2.29).

Case 2. Instead, say you paddle against the current with the same SOG of 4 knots. Then the relative water speed is 6 knots (4 + 2). Also, the relative air speed pushing you is 5 knots (9 – 4). At a relative water speed of 6 knots the water drag is 11.91 pounds. And the force of the relative air speed of 5 knots pushing you is 0.34 pounds. So the total drag you have to overcome is 11.57 (11.91 – 0.34).

Therefore, unless I made a mistake somewhere, I believe the example demonstrates that it’s easier to paddle downcurrent/upwind then vice versa, at any speed (not just as you approach hull speed). My actual paddling experience is consistent with this answer. Also, as you approach hull speed the exponent in the approximate exponential formula for water drag grows larger than 2.0. Also note that it’s less than 2.0 at slow paddling speeds. I validated this using John Winter’s drag program, named Kaper. Note, in a program I wrote I got answers consistent to the two cases at lower speeds. The examples were just easier to present.

One mistake I think you made is assuming that both wind resistance and hull drag are the same exponential functions. Yes, to a first approximation, the water drag function is sort of like Dw = W*s^2 and the air drag function is exactly Da = A*s^2 (where s is speed and A and W are constants). But, because water is much denser than air, W >>A so a small change in s changes water drag much more than it changes air drag.

The water drag values are from keelhauler.org/khcc/seakayak.htm and the air drag values were calculated from the standard air drag formula like the one published here https://www.grc.nasa.gov/www/k-12/airplane/drageq.html

-Leon

A Winter Brainteaser

Almost daily I paddle through the Palm Beach inlet going to and from the ocean (no, I haven’t met Trump yet and I keep away from Mar-a-Lago when the Coast Guard is patrolling).

The current in the inlet is generally about 2-knots and sometimes the wind is in the opposite direction. In fact, sometimes the wind exactly cancels out any drifting of my kayak; i.e., the current drifts me west at 2-knots and the wind pushes me east at 2-knots. So here’s a brainteaser.

Under the non-drift conditions above, which is easier (less exertion) to paddle: upwind/down-current or vice versa? Give reasons for your answer.

-Leon

Nick, have you given up on the J-racks?

1. Shoulder and triceps exercises for the long term.

2. If you can lift the kayak onto your shoulder tilt bow (stern) into Jhook in front of you to take half the weight and then tilt stern (bow) into Jhook behind you.

7 hours ago, josko said:

"...because most PFDs impede your stroke..."

I'm now wondering just how much an impedance to paddling a PFD is. Has anyone looked just how much time not wearing one could shave in a time trial? 

When Lisa and I trained in the Concord River she sometimes didn't wear a PFD because it inhibited her rotation. She felt the difference but I don't think we ever timed the difference. There was always at least a 1-minute difference between our 8.6-mile runs (probably due to wind). She also hates to wear a wetsuit for the same reason.

On 10/14/2016 at 8:39 AM, josko said:

I'm noticing a ton of surfski folks don't wear pfd's. I spoke to one recently, and learned that since they are leashed to their skis, the skis act as flotation (instead of a PFD). It looks like the same goes for SUP's???  Frankly, I never considered that being leashed to my kayak would absolve me from the need to wear a PFD. What am I missing here?

You could argue that a sea kayak is a pretty good flotation device too, as long as the hatches don't flood.

http://www.jerusalemonline.com/news/world-news/around-the-globe/watch-great-white-shark-breaks-through-divers-cage-24220

Wow, I'd rather be in a sea kayak with a bombproof roll.

7 hours ago, josko said:

That's the run on which I quit wearing my towbelt. (and I'm dying to see what my new Taran and Epic wing will do to the time.)

Oh, and the Gales are awesome IFF (if and only if) you like rough water.

Josko,

When Olympic sprint paddlers switched over to wing paddles their speed increase was about 2%. But they’re paddling in close to laboratory conditions (short distances with no waves). But variability of ocean conditions on different days might cancel any noticeable differences between two types of paddles. So don’t feel bad if your “faster” paddle blade isn’t always the faster paddle blade on a different day.

-Leon

1 hour ago, josko said:

I'm a slowpoke,

I

Slowpoke indeed. It's impressive. I'm sitting here drooling (with a broken fibular bone from a fall that twisted my ankle).

49 minutes ago, mattdrayer said:

  Maybe the ideal is zero-feather, I don't know, I have much to learn about it.

I think it's ideal for bracing considerations. But maybe not for the ergonomics of the blade catch or wind drag. I totally agree with all you said this time.

On 9/12/2016 at 10:00 AM, mattdrayer said:

I'll also add that feather angle is basically a dial for tuning the curve of the wing blade such that you generate optimal flow of water during your stroke.  It's similar to sailing, where you use the sheet to set your sail juuust right, so that it has the ideal shape in the context of your course and the wind direction to generate optimal lift.  So it's really important when you're experimenting with feather to be watching for clues that you're not getting optimal flow.  I look for things like water splashing on entry/exit, blade feels wobbly vs. smooth/firm during stroke, cavitation during stroke (feels like a rattle), and average speed on a known TT course is lower than normal.

My two cents:

I disagree that feather angle has anything to do with how a well-placed blade moves through the water. But feather angle might affect how you place your blade in the water and that will affect how the blade moves through the water..

For me, feather angle was a compromise between what was most comfortable for wrist flexion and my ability to brace and roll. I assume that for most paddlers no feather angle is best for bracing because both a left and right brace are identical. But, like me, some people require some feather angle to avoid too much wrist motion. I wish I would be more comfortable with no (0) feather angle.

-Leon

PS
I’m disregarding the air-drag consideration for feather angle here.

52 minutes ago, josko said:

Onno footbar seems a bit hard to find. However, the Stellar footplate looks sort of similar. Has anybody here had first-hand experience with it?

Josco,

I assume that the Stellar footplate is at least as good as the Onno (I couldn’t find the Onno either, Patrick’s link take me somewhere else).

The Stellar has pull straps so you can pull on one side while pushing on the opposite side (great for all-out racing).

Remember, since a kayak’s hull tapers in going forward, the standard slide tracks on each side of the hull are not parallel to each other. So you can’t use the original slide tracks with a footplate, unless you never want to slide the footplate forwards or backwards. The Onno system solves this problem by adding spacers to the hold the two tracks in parallel. I don’t know if Stellar provides the hardware to do this.

12 hours ago, josko said:

I just remembered that I have two peg positions; long for 'club paddles' and rough water, where I want my legs pretty much on the hull, and a shorter peg position for exercise paddles, where I really put the legs to work. Is there a way to foam out and still leave this kind of adjustability?

The Onno footbar slides on the same tracks as the foot pegs do.

4 minutes ago, jason said:

The website isn't too well setup.

http://www.onnopaddles.com/copy-of-sup-canoe

You're right, but you should have seen what it looked like 5 or 6 years ago. Like a disorganized hardware store. Now at it has useless flowers for you viewing enjoyment.