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From: PJ Rattenbury <ratten_at_uow.edu.au>
subject: [Paddlewise] Electric Pumps
Date: Wed, 02 Feb 2000 09:34:00 +1100
	Bob V wrote

	>I have considered -- but not yet tried -- attaching a short length (1/2
>inch?) of plastic pipe or hose to the base of the pump inside the strainer
>basket, effectively lowering the base of the pump.  Perhaps I'll get to that
>this spring (can't even get my obligatory work done, but I'll probably get
>to this first).
>
>Meanwhile, I'm not really unhappy with the volume of water that is left by
>the pump as is.  After all, the pump is meant to restore stability, which it
>does.  The 3/4 inch or so of water that the pump can't remove doesn't seem
>to be much of a problem for stability.
>
	Steve wrote:

	>Why would it be important to? 1.5 cm of water isn't much. You'll drip
>that much off your clothing when you reenter the boat. When I paddle
>white water canoe, there is routinely an inch or two (2.5-5 cm) of water
>in the bottom of the boat. When it gets to be over 4 inches (10 cm) I
>start to think about bailing.
>
Peter Rattenbury replies: 

	I agree, of course this level of water is not really a safety issue in a
hardshell with watertight bulkheads,   nor is it an issue in a Klepper in
calm or even moderate seas.  My concern is not getting wet,!  but the
weight of say just half an inch of water sloshing around in a high volume
kayak like the Klepper in ROUGH seas.  Even with fitted air bags in the bow
and stern sections.  I am talking about this sort of weight of water
sloshing bow to stern and back again in an open ocean situation with a
swell of two to three metres under a sea of say one to two metres. 
	I had not given this sloshing/weight effect much thought, but typically in
a capsize at sea,  either in practice or for real, I have ended up back in
the boat after a pump-out  with at least this quantity of water trapped,
but mainly hidden by the keelboards. One does not realise the weight or the
dynamics of the water unencumbered by bulkheads until you do the same
exercise on land.  Fill a seventeen foot boat with half an inch of water,
have a friend take one end , lift and tip the boat fore and aft and you
will be suprised at the destabilising effect of the water rushing back and
forth!
	It is a tribute to the inherent stability of the Klepper that this weight
shift is not really noticeable on the water.  And I realise that you can
paddle a Klepper fully flooded, due to the stabilising effect of the
sponsons. 
	BTW,  this reminds me of a vehicle ferry tragedy in the English Channel,
back in '88 I think.  A large fully loaded ferry put out from a French port
for England, but the bow doors were  not locked down properly.  As the
ferry gathered speed water began flowing unnoticed in and across the
vehicle deck, which of course ran the length of the vessel.  Eventually the
weight of the water, and the sloshing effect combined to capsize this
vessel of several thousand tonnes, at the cost of many lives. 
	But thanks Bob for the suggestion of extending the base of the pump. Good
idea, I will give it a go. I have been in touch with a large pump
distributor chasing a better scavenger pump, but it seems the Rule is the
best on offer.   Regards, PJ 

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From: Bob Volin <bobvolin_at_bestweb.net>
subject: Re: [Paddlewise] Electric Pumps
Date: Tue, 1 Feb 2000 21:49:42 -0500
Seems to me I recall that someone wrote about placing flotation materials or
other stuff in out-of-the-way places on the cockpit floor to act as baffles
to minimize the sloshing effect you describe.  It might be worth while
trying both approaches (lowered pump opening and baffles).  Let us know how
it turns out!
        Bob

From: PJ Rattenbury <ratten_at_uow.edu.au>
Date: Tuesday, February 01, 2000 5:36 PM


>My concern is not getting wet,!  but the
>weight of say just half an inch of water sloshing around in a high volume
>kayak like the Klepper in ROUGH seas.  Even with fitted air bags in the bow
>and stern sections.  I am talking about this sort of weight of water
>sloshing bow to stern and back again in an open ocean situation <snip>



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From: Robert C. Cline <rccline_at_swbell.net>
subject: Re: [Paddlewise] Electric Pumps
Date: Wed, 02 Feb 2000 23:06:56 -0600
That was me who wrote about that.  As per Matt's suggestion, I have acquired
a sea sock.  That might be sufficient.  I'll give a report on my
impressions.  Might be a couple of weeks.

Robert

> From: Bob Volin <bobvolin_at_bestweb.net>
> Date: Tue, 01 Feb 2000 21:49:42 -0500
> To: Paddlewise <paddlewise_at_lists.intelenet.net>
> Subject: Re: [Paddlewise] Electric Pumps
> 
> Seems to me I recall that someone wrote about placing flotation materials or
> other stuff in out-of-the-way places on the cockpit floor to act as baffles
> to minimize the sloshing effect you describe.  It might be worth while
> trying both approaches (lowered pump opening and baffles).  Let us know how
> it turns out!
> Bob

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From: Peter Treby <ptreby_at_ozemail.com.au>
subject: Re: [Paddlewise] Electric Pumps
Date: Mon, 18 Aug 2003 10:49:16 +1000
Adding to last night's post, here's a picture and a little info from Mirage
kayaks:


http://www.mirageseakayaks.com.au/features.html


click on "electric pump" to see a Rule 500 gph, fitted behind seat, waterproof
switch in a recessed deck depression, and battery in the day hatch
compartment.


Here's Peter Carter's page re pumps, obviously recently updated with
commentary about the Tasmanian circumnavigation write-up in Aug 2003
SeaKayaker:


http://users.senet.com.au/~pcarter/pumps.html


And here's a point of view on pumps:


http://www.nswseakayaker.asn.au/mag/35/pumps2.html


Cheers, 


PT


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