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PostPosted: Mon Aug 18, 2008 3:41 pm 
Before they introduced built-in cockpit in K1 and Kahuna in 2006, many people reported problems with Kahuna cockpit rim. The skin hem occasionally came loose off the groove in the rim. Happened to me a few times, then it stopped - may be began paying more attention to press the hem tight into the groove. Other Kahuna owners reported this too - and some didn't have this problem at all. But I don't remember anybody complaining about the same in K1. This puzzles me, as K1 has 4 times longer production history than Kahuna (early K1 models were different, but for the last 15 or 20 years (before switching to built-in rim in 2006) the fiberglas rim of K1 was pretty much same as in Kahuna, and identical with Big Kahuna).


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PostPosted: Mon Aug 18, 2008 5:09 pm 
lord high faltbotmeister
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Puzzles me too Alex, I was one of those with problems on my Kahuna. When I practiced rescue and recoveries, it would pop out in places. My K-1 has had no problems so far. I attribute it partly to the knob and coaming shim at fore and aft rib tops ( #3 & #4 ribs )
Image
( extreme left of picture), but I usually had problems along the side, not the ends, so i am not sure why. I seem to notice that the K-1, when assembled, is more rigid and structurly sound. The tubes are bigger than Kahuna, the ribs are HDPE and the rib mounts are different.

It was such a problem that I had the coaming replaced on the Kahuna. On the k-1, I think I will keep the fiberglass coaming..at least for now. I do like the rigidity of the fiberglass coaming, if it will stay in place. So far, so good.

Chris

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PostPosted: Mon Aug 18, 2008 7:10 pm 
I asked one dealer (not the factory) about this shim with knob, and was told that this was not to hold the skin hem in the groove. Don't remember now, what exactly was his suggested purpose, but this shim should help with keeping the hem in place too. In your photo this shim appears to go right into the groove - I think it was going over the coaming in the store, but may be I'm wrong?


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PostPosted: Tue Aug 19, 2008 8:41 am 
lord high faltbotmeister
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It does go into the coaming groove at about a 45 degree angle, then acts as a washer for the knob and then goes down 90 degrees over the end of the deck bar. I think its purpose is as a washer more than anything, but it fits tight over the skin and into the groove.

I am sure the shape of it has changed with the later sewn in coaming. As for the knobs purpose, it threads through the HDPE rib and into a deck bar hole the keep the bar in place. Unlike the key hole arrangement of the Kahuna.

I guess the reason for the metal washer ( now that I think about it ) is the keep the rib from flexing at the top of the rib. The washer holds the rib in place by grabbing onto the coaming. Of course on the Kahuna you have two straps under deck to cinch the rib in place.

Chris

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PostPosted: Thu Sep 25, 2008 6:09 pm 
This happens quite a bit with the seasocks in our K2, also generally along the sides.

Generally it's not too big a problem unless things are rough enough that wash is coming up onto the deck or we're practicing capsizing, and then we ship water pretty quickly.

I think part of the problem may be me over-inflating the sponsons, but I was also considering making some clamps/clips that looped under the outside edge of the coaming and back over the coaming and seasock edges into the cabin to hold the seasock edges in the groove.

Has anyone made or seen anything similar I could model them off?


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PostPosted: Thu Sep 25, 2008 10:01 pm 
Quote:
I was also considering making some clamps/clips that looped under the outside edge of the coaming and back over the coaming and seasock edges into the cabin to hold the seasock edges in the groove.

May be I'm missing something here, or K2 coaming is different from Kahuna and K1. It is the the deck hem that is in the groove (and comes loose sometimes), but not the seasock. Seasock goes over the outside edge of the coaming, same as sprayskirt, and stays on the coaming quite reliably. In 2006 and later models the new built-in coaming is less rigid and more round in cross-section, and I've heard that when you're doing a roll, some water gets in between the skirt and the coaming, while models with fiberglass coaming didn't have any leaks - but this is a different story.


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PostPosted: Thu Sep 25, 2008 10:08 pm 
Sorry, you're correct, it is the edge of the deck that is coming out of the groove in the coaming, so the water flows in over the deck and through the gap under the coaming. The inaccurate description I gave was a reflection of me typing in a semi-awake state while in a meeting... :oops:

So that should have read:

This happens quite a bit with the deck hem in our K2, also generally along the sides.

Generally it's not too big a problem unless things are rough enough that wash is coming up onto the deck or we're practicing capsizing, and then we ship water pretty quickly.

I think part of the problem may be me over-inflating the sponsons, but I was also considering making some clamps/clips that looped under the outside edge of the coaming and back over the coaming and deck hem into the cabin to hold the seasock edges in the groove.

Has anyone made or seen anything similar I could model them off?


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PostPosted: Thu Sep 25, 2008 10:43 pm 
lord high faltbotmeister
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Every boat is a little different with the coaming fit. My Big Kahuna had a problem with the skin coming out of the coaming. Usually when I was practising wet exits or in rough water. It didn't always happen, but did enough that it was annoying. My wife's Kahuna was less of a problem.

My K-1 so far has fit well with no slippage. I have not had the boat long, but it just seems to be a tighter, more snug fit.

I have thought ( when I had my Kahuna ) of some sort of coaming clamps, but never pursued the idea.

Chris

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PostPosted: Fri Sep 26, 2008 8:26 am 
Hi, we use a few pieces of duct tape to keep the skin in place.
it works fine. might not be an elegant solution, but it's quick. clamps or clips would keep the seasock from fitting tight.

greetings from across the atlantic pond


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PostPosted: Sat Oct 18, 2008 7:11 pm 
My '05 K1 has this problem. I just got a reply from Feathercraft in which she suggested that the skin has shrunk a little. The solution I was directed to is to fold the skin inside-out, fit the coaming on while reversed and soak it overnight in a tub, then after awhile flip it right-side out and re-assemble it. I'll let you know if this makes any difference.

I was considering making slip-on clamps modeled after something from the world of commercial photo studios. Take the proper diameter stock PVC pipe and cut little sections a few inches long, then slit a slot in them lengthwise, but it has to be just the correct width, which will take some experimenting. The PVC is strong, slightly springy and a little flexible, so it will stay in place if done right and hold snugly. :wink:


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PostPosted: Sat Oct 18, 2008 11:21 pm 
Quote:
Take the proper diameter stock PVC pipe and cut little sections a few inches long, then slit a slot in them lengthwise, but it has to be just the correct width, which will take some experimenting. The PVC is strong, slightly springy and a little flexible, so it will stay in place if done right and hold snugly.

Such clamps are inexpensive solution when you need a lot of them, like in boat building and other projects that require temporary clamping. I've made a number of them and used for all kinds of DIY projects. The main problem is that it's big - usually 1.5" or 2" diameter pipe. Even when the project didn't require a lot of force, like holding down a thin vinyl hose in automated plants watering system (wonderful gadget, btw, for keeping indoor plants alive for 2-3 weeks), when touched occasionally, those clamps sprang off the pot rim. This wouldn't work on a kayak cockpit rim, with hands and paddle moving around all the time.
And, as others here mentioned, big clamps will interfere with seasock and sprayskirt.


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PostPosted: Sun Oct 19, 2008 11:21 am 
lord high faltbotmeister
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It is really tough to find something thin enough and strong enough to work. I assume Feathercraft would have come up with a cheap fix/accessory had it been easy. I think the loose coaming is a minor problem throughout the entire line ( although they did reinvent the coaming design didn't they )

As I have said before, this problem has not occurred on my K-1, but had been a problem on both my wife's Kahuna as well as mine. The biggest problem is how small the groove is in the coaming and how difficult it would be to 'sandwich' a clamp in there effectively. A small flat stainless steel screw that would run through the inner ( cockpit side ) coaming groove and into a sewn in or threaded, or clamped in ( like an eye on sailing cloth ) nut on the hard part of the skin ( the part that is stuffed into the groove ) might work, but I am sure that would bring on a host of other problems such as holes enlarging in the fiberglass or alignment problems when installing and not to mention keeping track of the tiny screws as well as a screw driver :roll: !

Chris

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PostPosted: Sun Oct 19, 2008 7:14 pm 
I cut a test PVC clamp today, it seems to fit over both the skin edge and the coaming itself just snugly enough. I'm going to cut a series of them later in the week and seat the thing again, clamp them in place and then re-inflate the sponsons. I'll let you all know what happens.

This solution cost me little more than time to cut and file, I had some spare PVC laying around. BTW, I beveled the inside edges after finding the right size for the slot, for a better grip. If they work I suppose I'll paint them black, too. So far my inclination is that it will work. Stay tuned.


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PostPosted: Tue Oct 21, 2008 8:26 am 
lord high faltbotmeister
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njpaddler wrote:
I cut a test PVC clamp today, it seems to fit over both the skin edge and the coaming itself just snugly enough. I'm going to cut a series of them later in the week and seat the thing again, clamp them in place and then re-inflate the sponsons. I'll let you all know what happens.

This solution cost me little more than time to cut and file, I had some spare PVC laying around. BTW, I beveled the inside edges after finding the right size for the slot, for a better grip. If they work I suppose I'll paint them black, too. So far my inclination is that it will work. Stay tuned.



Sounds great, would like to see pictures as well as seeing if the sea sock & spray skirt works over it all.

Chris

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