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Re: Review: Electric Bilge Pump for Kayaks
By:Bill Hamm
Date: 8/13/2009, 2:47 pm

: Landon, I think it's a great idea. If you make a good product and market it
: well I think you could price it around the price of a decent spare paddle
: or LED bike headlamp. Somewhere around $125-$150. But it has to WORK and
: be durable, not a variation on the Attwood WaterBuster. Ten years ago I
: sent them a letter saying there was a potential market for an upgraded
: WaterBuster for around $75 but no response.

: I think the design challenge is clarifying method of operation and
: installation options. My preference would be a couple of options from
: automatic to manual to something inbetween(haven't figured that yet) with
: the switching mechanism free from accidental activation. I'm not a fan of
: external switches and wiring as you've got more routes for leaking and
: corrosion. Make it like any manual pump, self contained and transportable.

: Your impression about pumping is absolutely correct, assisted rescues make a
: lot more sense than pumping out. The primo candidate for electric pumps is
: doubles as the odds of pumping out a double in rough conditions is about
: nil.

: I'd look to market this pump outside of the kayaking community even if that's
: your intended market because a well designed portable pump for $125 is
: about what a manual pump would cost to install in a 30' sailboat, ie.
: Whale Titan. The Attwood Waterbusters sells for a reason, it's cheap and
: it works,,within limits. Me thinks you'll find more boat owners of all
: types tossing a DURABLE portable electric pump in their lockers than you
: will sea kayakers drilling holes in their kayaks. Have you used the
: Attwood Waterbuster? It works but has waterproofness limitations and
: breaks easily if dropped. I went through three putting 3 D cell 2v gel
: cells in one and 5 Nicad in another instead of the regular 3 1.5v D cell
: alkalines. It moved a lot more water than the stock 4.5v setup. The
: problem is that the switch is barely waterproof, needs to be sealed and
: the seal at the impeller is inadequate once the motor stops working and it
: draws a vacuum while cooling sucking standing water into the unit.

: Like homemade versions I've seen on the 'net I'd go for a small rectangular
: dry box size about 3"x5"x7". I'd leave the method of
: mounting to the customer but the marine market should make it heavier than
: water so all a person has to do is tether it and toss it in a dinghy. For
: the kayak market you can do what Attwood does is have a removable steel
: plate or divers lead weight so that it can be secured to the bottom of the
: kayak in it's prefered spot and impervious to worst case use. My
: suggestion would be to leave that totally up to the paddler but at least
: have the design friendly to behind the seat, front of the seat, or at the
: feet installation with controlls/settings appropriate for all three
: positions.

: For cost reasons I'd go for 10 AA 2650 mamphr NiMh cells instead of some
: gucci lithium ion battery. You could replace the batteries if needed. 12v
: 2.5 amp/hr should empty the boat quick enough.

: One more time, market it to the marine market where there are more customers
: and durability is the issue. Being able to drop a portable pump into a
: swamped dinghy at the docks in cold weather and walk away from it will be
: a more common customer need than an owner of a sea kayak considering
: adding four more pounds on the kayak and drilling holes.

: I like the Waterbuster size and shape, handle on top, inlet on bottom and
: outlet on one side with hose. Except make it tough. A dry box shape would
: work with attachment point for removable/optional weight. Look at the kind
: of micro switches on some electronics where the plastic only has to flex
: in a fraction of a mm but it takes a concerted effort to work it. Planet
: Bike Super flash rear tailight has a switch like that. It eliminates all
: the issues of thick special purpose rubber cover that can weather and
: tear.

: Just to repeat, go into any marine hardware store and look at their pumps,
: check out outdoor/marine/jon boat/rv suppliers. That market is 100times
: bigger than sea kayaks. Don't go for a simple on/off switch. Make it like
: the DiNotte head lights for bicycles. User friendly, easily replaced
: batteries, easily installed and removed.

: Then get someone in China to make it.

Number one problem with these things specially with most kayakers is the batteries can't need charged every week or it'll be a marketing failure.

Kayakers seem to be able to very nicely ignore their boats between outings (me too) :)

Bill H.

Messages In This Thread

Review: Electric Bilge Pump for Kayaks
LM -- 8/11/2009, 11:49 am
Re: Review: Electric Bilge Pump for Kayaks
Mike Savage -- 8/15/2009, 6:09 pm
Re: Review: Electric Bilge Pump for Kayaks
LeeG -- 8/13/2009, 2:23 am
Re: Review: Electric Bilge Pump for Kayaks
Bill Hamm -- 8/13/2009, 2:47 pm
Re: Review: Electric Bilge Pump for Kayaks
LeeG -- 8/14/2009, 2:40 am
Re: Review: Electric Bilge Pump for Kayaks
mike allen -- 8/14/2009, 2:56 am
piezo electric laminate
LeeG -- 8/14/2009, 10:56 am
Re: piezo electric laminate
Bill Hamm -- 8/14/2009, 12:31 pm
doubles and dinghies
LeeG -- 8/15/2009, 3:05 am
Re: doubles and dinghies
Bill Hamm -- 8/15/2009, 5:47 am
Re: doubles and dinghies
LeeG -- 8/15/2009, 1:51 pm
Re: piezo electric laminate
Matthew -- 8/14/2009, 2:10 pm
Re: Review: Electric Bilge Pump for Kayaks
Brian Nystrom -- 8/11/2009, 8:57 pm
Re: Review: Electric Bilge Pump for Kayaks
LM -- 8/11/2009, 9:00 pm
Re: Review: Electric Bilge Pump for Kayaks
Don Lucas -- 8/12/2009, 9:45 am
Re: Review: Electric Bilge Pump for Kayaks
bromasi -- 8/12/2009, 1:00 pm
Re: Review: Electric Bilge Pump for Kayaks
Etienne Muller -- 8/11/2009, 5:42 pm
Re: Review: Electric Bilge Pump for Kayaks
Glenn -- 8/11/2009, 7:03 pm
Re: Review: Electric Bilge Pump for Kayaks
LM -- 8/11/2009, 9:02 pm