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No More Seat Puddle w/ self draining scupper
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Author:  Revo_1756 [ Mon Mar 18, 2013 2:14 pm ]
Post subject:  No More Seat Puddle w/ self draining scupper

As I posted previously I promised to post my solution.

Previous post so I won't repeat myself here.
viewtopic.php?f=11&t=46681

First you need to get some trout balls.
Catch a trout and ... :lol:

8mm Floating trout balls or beads as they are also called.

Image

Image

#1) Using a #6 hex shank countersink I drilled through the cap from underneath. This creates a drain hole in the cap and a taper for the bead to fit into.

#2) The 8 mm trout beads have a hole for fishing line I filled by pressing in tip of a wooden toothpick soaked with glue and snap off and press in so none protrudes.

#3) Place two (2) trout beads into cap (2nd one adds to the bouyancy and pushes the first one into the taper). The beads are not hollow but do float.

#4) I cut a piece of flat plastic from another scupper and glued to the bottom to keep the beads in. Use care not to get any glue inside the cap. File the crossbar smaller than the threads so it does not interfere with the screwing in of the scupper.

You have a home made self draining scupper. The venturi effect speeds the drainage. Works on the principle of an old ball check snorkel.

Secondly to keep the puddle from occuring in the first place I am taking a 12" x 12" x 1/8" neoprene rubber sheet and cutting a deflector and placing over the handle recess to stop the geyser effect by deflecting broadside waves that channel into the recess.

I have two of the scuppers in my revolution and they work very well.

I did a lot of trial and error cutting tapers with dremel grinding stones and using o rings inside the cap. This worked best. The taper cannot be too big or the bead will not check the flow.

Revo

Author:  Revo_1756 [ Thu Mar 21, 2013 8:47 am ]
Post subject:  Re: No More Seat Puddle w/ self draining scupper

Forgot to add the Trout bead info & where to get them.

http://www.ebay.com/itm/TROUTBEADS-SNOW ... 4d041c8cbc

Revo

Author:  Geordie [ Thu Mar 21, 2013 8:44 pm ]
Post subject:  Re: No More Seat Puddle w/ self draining scupper

Great work Revo and good to see someone thinking of a simple solution.

I have tried a few different options with parts from the gear that I am familliar with, scuba diving and snorkel drain valves. But these are hard to find parts of the right size and price.

The floating ball valve has potential to be an excellent option as you can find the right parts.

I see it has still been a lot of experimentation and work to get it right, great work. I will be interested to hear how it works for you.

(I also added a comment you might be interested in re: the handle scoop deflector in your other thread)
Geordie

Author:  Revo_1756 [ Fri Mar 22, 2013 5:36 am ]
Post subject:  Re: No More Seat Puddle w/ self draining scupper

Thanks Geordie,

I approached the solution trying to utilize the existing supper without too much modification or losing the retainer clips.

It is a DIY fix and not a machined/tooled part. I have tested it screwed through 3" deep plastic container and pressed into a pan of water. It kept water from coming in and at times water seeped between gasket & container even with plug screwed in tight and not up the cap. Filling the container it drained out.

Once it worked at the sink I put two in my revolution took it out on the lake and with a cup filled my seat well numerous times. The water drained out (even faster in motion) and it did not fill back up. It also drained sitting still.

Now if it were a machined part with a hollow ball and a spherical recess it would be the ideal scupper.
Image

Revo

Author:  Chexone [ Wed Apr 17, 2013 1:55 pm ]
Post subject:  Re: No More Seat Puddle w/ self draining scupper

Pretty brilliant solution to wet-butt syndrome. Thanks for sharing.

Author:  petersumm [ Thu Oct 03, 2013 1:24 am ]
Post subject:  Re: No More Seat Puddle w/ self draining scupper

Are you still happy with this arrangement?

It looks like the flow rate would be limited by the small gap between the stopper wall and the valve (or if a smaller ball was used, the size of the top hole).

I'm looking to do something similar, with a 9.53mm diameter polypropylene (floating) ball (e.g. http://www.minibearings.com.au/store/partslist/ballspolypropylene/ballspolypropylene/all/1/) and creating a cage so that the ball can come partially out of the tube (using the existing structure with a couple of extra pieces of plastic to stop the ball escaping).

Thoughts?

Author:  Revo_1756 [ Thu Oct 03, 2013 4:59 am ]
Post subject:  Re: No More Seat Puddle w/ self draining scupper

The flow around the ball actually is quite good with the 8mm ball. I am still refining. The trout bead is not 100% spherical and your idea of the polypropylene ball will resolve that.
I am working on a better radial recess at the top. Mine have been more of a taper than radial yet work nicely.

My experimentation was interrupted by a flood in my house and months of renovations. I sprained my back and that has kept me out of my kayak for quite some time. I am finally getting back into it and will continue to improve my scuppers.

I am ordering some of the plastic balls which will work much better.

The functionality of the scupper depends totally on how well the ball seats at the opening. Too big a hole and the water will flow past it. The polypropylene ball can be bypassed with enough pressure. I have found a smaller hole and larger ball worked best. The venturi effect draws the water out faster even with a small hole.

IMO it is not so much the speed of the drain but to drain the seat so you do not sit in a puddle for a prolonged period of time. One can only do so much with the existing scupper plug.

Revo

Author:  jahaiap [ Thu Oct 03, 2013 7:52 pm ]
Post subject:  Re: No More Seat Puddle w/ self draining scupper

Revo_1756 wrote:
I am working on a better radial recess at the top. Mine have been more of a taper than radial yet work nicely


http://www.ebay.com/itm/HSS-Ball-Nose-E ... 19ca6cc9b3

Maybe an 8 or 9mm ball end mill?

Author:  Revo_1756 [ Fri Oct 04, 2013 5:34 am ]
Post subject:  Re: No More Seat Puddle w/ self draining scupper

Thank you for the suggestion Jahaiap

I love the brainstorming you find in this forum. I have already purchased some round ball end grinding stones before the renovations and will try those first. The top thickness of the scupper plug is so thin it would be easy to drill through. I start with the countersink and try to round the taper inside for a better fit. My previous attempts were with a tapered grinding tool as well. The ball end should work even better. Same principle as the milling tool. The adjustable speed of the rotary tool aids in making minor adjustments.

Hopefully will have time to work on it this weekend.

Revo

Author:  petersumm [ Tue Dec 24, 2013 1:15 am ]
Post subject:  Re: No More Seat Puddle w/ self draining scupper

Back again, still looking for a solution...

The polypropylene balls don't appear to be light enough, and so don't stick forcefully enough in the hole, and so water leaks in. I'm heavy enough (93kg) that the bottom of the seat is just slightly below water level, at least in fresh water with a cart strapped on the back.

I've tried putting an O-rings inside the plug, but this hasn't helped.

When peddling, the Venturi effect doesn't seems strong enough to drain the seat, at least not at cruising speeds (6km/h). When I peddle really hard (10km/h), it drains, but I'm not sure whether that's Venturi or the kayak rising slightly out of the water. When I slow down, the water comes back in again.

Does anyone know what sort of speed is required to get Venturi happening?

Can anyone recommend a lighter (possibly hollow) ball? It needs to be spherical, and I'd guess between 9 and 10mm in diameter.

Also, can anyone tell me the exact inside diameter of the plug? Is it consistent between different plugs? I suspect that a ball that almost fills the plug would work better.

Thanks,

Peter

Author:  Tom Kirkman [ Tue Dec 24, 2013 8:28 am ]
Post subject:  Re: No More Seat Puddle w/ self draining scupper

I tinkered with some one-way or self draining scuppers but found that because the seat tub was below the waterline, any water than splashed in, wasn't going to go out anyway. So I gave up on that idea and just raised the seat tub bottom. No more puddle to sit in now and nothing to break or go wrong. And anything that splashes in, just runs right back out.

Author:  Revo_1756 [ Wed Dec 25, 2013 4:14 pm ]
Post subject:  Re: No More Seat Puddle w/ self draining scupper

After a few attempts and new balls that di not have enough bouyancy I am going to try the siphon valves used in this post,
viewtopic.php?f=71&t=45380&p=222298&hilit=Scupper+drain+siphon#p222298

I will report on my results.

Revo

Author:  Ryderfzr [ Mon Dec 30, 2013 10:47 pm ]
Post subject:  Re: No More Seat Puddle w/ self draining scupper

Hey guys
First I want to say thanks for all the great info on here. I have been seeing post about these scuppers and others for a while. and I hope this info helps someone. I found these yesterday after exhausting searches on this topic. I am going to purchase them this week and I will post my results for everyone http://www.h2okayaks.com/engine/shop/product/52851/Pair+Medium+Kayak+Gear+Self+Draining+Scupper they are the only ones that I have found that only come in one size

Author:  petersumm [ Tue Dec 31, 2013 1:55 am ]
Post subject:  Re: No More Seat Puddle w/ self draining scupper

The feedback from this thread isn't encouraging.

What type of ball did you use in the end? The solid polypropylene ones appear to be two dense. There are hollow ones available that look worth a try, but I'm still trying to find someone who will sell me less than $50 worth.

Author:  Revo_1756 [ Tue Dec 31, 2013 5:38 am ]
Post subject:  Re: No More Seat Puddle w/ self draining scupper

I used the solid plastic polypropelene. I have not found hollow ones. Where did you find hollow balls that size?

Revo

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