I've completed a prototype for the breath-powered pump, and tested it in the bathtub (yes, another use for a bathtub). The pump works brilliantly! I managed to pump 19 liters a minute, even while out of breath after some serious exercise. Of course a bath-tub-test is no real-life bailing condition, but lets say I will manage 15 liters per minute in real life. I think that passes most foot- and handpumps. I will go ahead and install it in my boat. For those interested in the design: The pump house is a PVC drainpipe, 12 cm diameter, 30 cm length, closed at both ends. This makes a container of 3 liters. This pipe is laying flat behind the seat in my boat. The pipe fills with water from the cockpit through 5 holes, 22 mm diameter. With a strip of soft vinyl covering the holes, I made one-way valves. Once the pipe is filled, I pressurize it by blowing on a 12 mm gardenhose. This pressure pushes out the water through a 25 mm hose. When the pump is completely submerged, it fills with water in 2 seconds. It takes 5 seconds to blow the water out. When the pump is not submerged, it will not fill spontaniously. Maybe I'll have to suck the air out, but I hope that pushing my sprayskirt will do the trick. In my "humble" opinion, I created a serious alternative to foot-, hand and electric pumps. Anybody who wants to pay me a million dollars for the design is quite welcome. Anybody who likes the idea and wants to create his own for his own kayak is also welcome, although not quite as much. Niels. *************************************************************************** PaddleWise Paddling Mailing List - Any opinions or suggestions expressed here are solely those of the writer(s). You must assume the entire responsibility for reliance upon them. All postings copyright the author. Submissions: PaddleWise_at_PaddleWise.net Subscriptions: PaddleWise-request_at_PaddleWise.net Website: http://www.paddlewise.net/ ***************************************************************************
Niels wrote: > I've completed a prototype for the breath-powered pump, [...] > managed to pump 19 liters a minute, even while out of breath after some > serious exercise. Of course a bath-tub-test is no real-life bailing > condition, but lets say I will manage 15 liters per minute in real life. I don't quite recall the earlier messages about this topic. Do you intend to use it as a backup for another pump or as a "stand-alone-application"? :-) Have you checked how much water is in your cockpit after a self rescue / assisted T-or-other-rescue? And how much time x it will take to pump the most important amount of water (nevermind the last 5 liters) out of the cockpit? Have you been breath-operating your pump for this x amount of time? Sitting in cold water in the bath tub (properly dressed for immersion, of course :-))? As soon as I have an extra million, I'll buy your design. Promised. Cheers, Marian Marian Gunkel, Berlin, Germany www.mariangunkel.de *************************************************************************** PaddleWise Paddling Mailing List - Any opinions or suggestions expressed here are solely those of the writer(s). You must assume the entire responsibility for reliance upon them. All postings copyright the author. Submissions: PaddleWise_at_PaddleWise.net Subscriptions: PaddleWise-request_at_PaddleWise.net Website: http://www.paddlewise.net/ ***************************************************************************
Marian Gunkel wrote: >>>Do you intend to use it as a backup for another pump or as a "stand-alone-application"? Have you checked how much water is in your cockpit after a self rescue / assisted T-or-other-rescue? And how much time x it will take to pump the most important amount of water (nevermind the last 5 liters) out of the cockpit? Have you been breath-operating your pump for this x amount of time? Sitting in cold water in the bath tub (properly dressed for immersion, of course :-))? <<< I have not checked yet how much water stays in the cockpit after a rescue, how it works while sitting in cold water (I used WARM water in the bathtub and got only my hands wet) and didn't check how long I can keep pumping without passing out. Valid questions, but I can't answer them from the bathtub test. I am going to build the pump and perform the next test in a swimming pool, after that I can tell you more. One question I can answer: This pump is meant as the MAIN pump in my boat. I will carry a handpump as a backup. *************************************************************************** PaddleWise Paddling Mailing List - Any opinions or suggestions expressed here are solely those of the writer(s). You must assume the entire responsibility for reliance upon them. All postings copyright the author. Submissions: PaddleWise_at_PaddleWise.net Subscriptions: PaddleWise-request_at_PaddleWise.net Website: http://www.paddlewise.net/ ***************************************************************************
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