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Old 03-29-2011, 01:48 AM   #136
Fiskadoro
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Join Date: Jan 2009
Posts: 1,509
My kayak Hoopnet

I originally posted this in back in 2006 on another board, but I was going through some archives, and found it again so I thought I'd re-post it here.

So....Here it is...my kayak hoopnet....



The nets one of my designs: essentually a redesign of this net I made in 2005 using the same netting:



It was a "working" prototype that I'd been playing with for while, but I had some issues with it. The first net had too big of an opening which produced too much drag in the water.

Th newer one has the same size opening as a Danielson cone but the top ring is an inch and a half higher, and the base is only 28 inches across vrs 34 inches on the Danielson net and 36 inches on the Promar net.

Since the base is smaller it has a lot less drag coming up through the water. It pulls easier and faster then either the Promar or the Danielson net.

Like the Promar cone, my net folds down for flat storage.


I don't know how theirs work as I never owned one but my design has three pieces of pivoting 1/2 inch tubing that that turn on the 1/4 inch stainless hoop ring. The bridle is made from three lengths of 250 pound Mono leader. It runs down through the tube legs and it's tied to the Bottom 3/8 hoop.

Basically to get the hoop to stand up and pull into shape you just have to pull up on the bridle.





Once it's up you just have to make sure the knots go up into the legs and it's ready to use.





I've pretty much got this one worked out.

It's a great net. It sinks like a stone, pulls easy as Promars original smaller flat nets, and catches more bugs then they do.

From playing around I've pretty much figured out that the crucial distance in a cone net is not the diameter but the entrance or top rings distance and height ratio to the bug.

Most bugs are lost one of two ways in a basket style net.

Either the bug flips over the ring before it gets high enough to block his initial jump or climbs out on the way up.

So the advantage of larger Basket style net compared to a smaller one is the ring edge is simply further from the bug at the start of the pull.

Conical nets do not have the same constraints

With a conical net the top ring is already above the bug: the idea being it is it's high enough to make it hard for the bug to intially flip out.

It's all about exit angle.

When the exit angle is too steep for the bug to make on his first flip he undershoots the exit and ends up stuck backwards against the net wall or downward facing side. If he keeps flipping he just drives himself deeper into the net.


The crucial distance is then not base diameter on a conical net but the entrance ring distance and height ratio to the bug.

I can't figure out why the net manufacturer's have not figured that out but even the new Promars are much larger at the base which makes them harder to pull.


Here's the old style cone geometry compared to my new net:



The larger the top ring diameter or the lower the ring, the better the angle is for swimming out. So the trick is to have a relatively small opening high enough above the bugs head that he can't make the angle when he tries to kick out.

I've not used the Promars cones at all but I have a few Danielson conical nets.

The D cones are made like traps. I think the guys who designed them thought that lobsters would climb in, feed, then not be able to find their way out. I don't believe that at all..... . Crabs...maybe.... but not lobsters.

I've watched bugs feed in my Danielson nets with my IR Infrared camera and once they feed they get out fast.

The Danielson nets work great but my three gripes are.....

One: I think the top ring is too low and that bigger bugs sit on top and feed without getting in the net . Two: they hard to pull because they are too big and too heavy. Three they take up a lot of room in a boat and are impossible to carry on a kayak.

The plus side you don't have to pull them that fast because once you have a bug in them it's very hard for them to get out.

I have not used the larger Promars but I can tell just by looking they are an improvement in two ways. One the top ring is too high for bugs to perch on and feed and two: they fold for storage.

Still they are huge, heavy and I bet they are a biiiiittttch to pull.

One thing for certain: Now that Promars come out with a two cone nets and the DFG has OKd them there is no doubt that cone nets are here to stay.

Cones are ideal for kayak because it's hard to pull as fast when your sitting down. Unfortunately the current ones commercially available are probably a little harder to pull then they need to be.

Here's one more pic a standard D cone on top of my cone.



You don't have to be a rocket scientist to figure out why mine pulls easier, and with it's higher ring it should catch more and larger bugs.


I have no plans to market these nets right now but they could be marketed. I think it's pretty much the ideal net for Kayaking.

Seems to work so far for me:



...and your welcome to make your own.

Tight lines, Jim

Last edited by Fiskadoro; 03-29-2011 at 05:03 AM.
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