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Re: on a roll
By:Lee Gardner
Date: 5/5/2001, 12:17 am
In Response To: BATTERY POWERED BILGE PUMP (Steve Tilders)

Steve, It is great that you are listening to the customers. I'm guessing that the cost of the system you describe will cost upwards of $175-$200? Which is reasonable considering the cost of making ones own foot pump is around $50 just for materials and a British footmounted pump is around $175 (is that right guys?). I called the folks at Attwood about ways that they could modify their $32 Waterbuster for kayak use but who knows if they decide to do something.

I'm just shooting the breeze here, but you might look at lighting systems for bicycles as an indicator of price ranges for useful devices that enthusiasts use. Marginal systems for $80, good ones for $120, max wattage above $200. I don't think an owner of a $1000-$3000 kayak with $200 paddle and $1000 of gear would quibble much over an electric pump that costs less than $100, considering the alternatives. The number of customers willing to spend >200 are much less. If your system was engineered well it could well be worth $229 like earlier high end lighting systems cost, I just wonder if the number of units made would be worth your while. With some design compromises and cost under $120 the sales would be much larger. Just making the numbers up but you get the idea.

14GPM is a lot of water. I would first look at how fast the existing manual methods are and their respective costs. An electric pump that moved water no slower than a hand pump is still a tremendous improvement simply because the paddler can have his hands free. That high capacity pump you mention would be very useful in doubles where the amount of water is signicantly greater than in a single but the market for doubles is much smaller than singles. The size of battery required for that unit puts some constraints on the cost and ease of use.

Here are the design goals I'd shoot for:

1. pump water at a rate no less than a strong person with a hand pump can accomplish. 5gpm?

2. Battery and pump one unit. Reduce to a minimum the number of openings or controls. No external wires, no plugs requiring waterproofing,no remote switches. One unit with a handle and tie down points or moldings, one master switch, one hose outlet with possible remote hose inlet.

3. Ease of installation and removal, 3ft 1/2" hose with standard plastic garden hose fitting to be screwed into through hull fitting, through hull fitting has cap and tether when pump is not in boat. Like the Attwood the pump could be used in boats without special through hull fittings, that way you wouldn't lose the large number of people with plastic and kevlar boats that wouldn't feel comfortable with cutting into their boats. I've used the Attwood and it works just fine with the threaded hose end tucked tight under the skirt at the edge of the coaming. That's on a glass and plywood kayak. I'm sure there are some skirt/coaming combinations that wouldn't accomodate it or would pop off more easily when rolling but there are some skirt/coaming combinations that don't stay on well anyway. Any person that is able to roll and is looking for a good gadget will be willing to modify the boat to be able to roll. The typical buyer of a $1100 Perception Corona will be happy to buy a safety device that he can put in his boat, the number of people that have bought $60 worth of paddle float and pump then never learned to become proficient in their use is probably pretty high. They're the folks that will be buying the pumps for $120.

4. Here's the hard part, make it strong enough to handle being droped onto concrete from 3ft. Another reason to reconsider the high capacity pump you mention with the heavier gel cel.

5. Make is waterproof enough that it can run, die out, and not lose waterproofness should it sit in water for a few days. The Attwood would warm up then suck in a little water if it sat in standing water for a while after being turned off. At least I'm assuming that's how the teaspoons of water got in there.

6. No nicads, they lose too much charge sitting around. Gel cells are better. It would be nice to have something that can sit around for a month with a full charge then still be useful. Although you'd be pretty clever if you transfered the full cost and designed it to use any of the 12v nicad packs on portable drills, they're are a lot of those at Home Depot, sale price with and without battery pack. Another good reason for a smaller pump.

7. The $32 Attwood with three D size gell cells pumps plenty of water, holds a charge and I believe will pump for longer than an hour, but will probably burn out that little motor if it had to run too often for that long. It just breaks easily and can't tolerate sitting in standing water for days.

8. Look at the size of a small Pelican box (my favorite small lunch box size) I think it's around 8.5"x6.5x3.25". That's about the maximum size for a complete unit for my desires. It'll fit in front of my seat, behind my seat, up near the front bulkhead,etc. and will occupy less space than a big foot pump or hand pump. I'd look towards the smallest pump possible for the purpose so that the battery capacity isn't pushing the price and size figure up.

9. Lastly, on switch with automatic on off and maybe a green/red LED charge status light, but most folks will notice the pump laboring about the same time the LED indicates low voltage. With simple electronics when the one switch was turned on the pump would go on for a set number of seconds to indicate ok function and battery charge then turn off untill water sets it off.
Maybe make it a three position switch but I wouldn't go overboard like the bike light systems have with all kinds of bells and whistles, unless they can be done without much cost. One cylinder make and break engine sound would be nice. ok , got lost there.

10. no velcro, hard tie down loops or fastek buckles and straps. The pump should not get dislodged if the boat tumbles through the surf or gets hit by ones feet.

11. not sure if you can do this but if the pump and batteries are small enough make it able to float.

12. Pick it up out of the kayak, open it up, pull out plug and plug into auto cig. lighter. so it can dry and charge with ventilation.

13. IMAC like translucent plastic is probably fading as a gotcha but don't make it look like it came out of a marine hardware store. Make it look like a divers flashlight (princeton tec) or have decorative lines like the divers knives you see in catalogs, or anything that could be sold on a shelf in a sporting goods catalog (Cabelas, LLBean,etc). Just don't make it look like another electric bilge pump. You want the person with the SUV to consider using it pump water into a folding canvas bag so they wouldn't have to step into the water, or the home brewer to consider using it to move the first fermentation into the...oops wrong imagery there. The Cabelas fisherman to consider using it to empty the live well, heck I don't know what fisherman do but imagine it in other places than just a kayakers cockpit,,,,like the cheap portable tire inflators are kind of an impulse item,,,"hey, I could use one of those things,, you know honey,, to pump some water, I'll get one for the canoe"

I think there is definately a market for it under $150 if it is really made well and isn't awkward to remove or maintain a charge. You will sell a lot more if it costs $75,,thinking of the inexpensive portable drill, consumer electronics, cheap cameras, lower cost necessities (pfds, paddles, tow belts, first aid kits, flares/flashlights/emergency gear) market. Around the cost of SeaLines(?is that right) new rudder and footbrace set-up,$235 I think, you'll have to convince people that it's the neatest thing since a bread making machine with different colored LEDs, power takeoffs, accesories, camp lighting with 3white LEDs, with a console for the Palm Pilot. Otherwise keep it very simple, strong and reliable. Look at what paddlers pay for paddles,pfds,and skirts, $50-$150.

Messages In This Thread

BATTERY POWERED BILGE PUMP
Steve Tilders -- 5/4/2001, 10:35 am
Re: BATTERY POWERED BILGE PUMP
sage -- 5/6/2001, 10:58 pm
also
sage -- 5/7/2001, 9:49 am
Re: BATTERY POWERED BILGE PUMP
Robert D. Newton -- 5/5/2001, 1:34 pm
Re: BATTERY POWERED BILGE PUMP
Dale Frolander -- 5/5/2001, 4:29 am
Re: on a roll
Lee Gardner -- 5/5/2001, 12:17 am
Re: on a roll
Lee Gardner -- 5/5/2001, 12:26 am
Re: BATTERY POWERED BILGE PUMP
Jason Koldewijn -- 5/4/2001, 9:10 pm
Re: BATTERY POWERED BILGE PUMP
Alex Warren -- 5/4/2001, 8:41 pm
Re: BATTERY POWERED BILGE PUMP
Jim Pace -- 5/4/2001, 6:42 pm
Re: BATTERY POWERED BILGE PUMP
Randy Knauff -- 5/4/2001, 6:41 pm
Re: BATTERY POWERED BILGE PUMP
Mitch Isoe -- 5/4/2001, 3:22 pm
Re: BATTERY POWERED BILGE PUMP
Shawn Baker -- 5/4/2001, 6:07 pm
Re: BATTERY POWERED BILGE PUMP
Shawn Baker -- 5/4/2001, 12:37 pm