Re: [Paddlewise] foot pumps

In a message dated 2/1/99 1:29:57 PM Eastern Standard Time, bhume_at_micronet.net
writes:

<< I'm seriously thinking of installing a footpump.  It was 
 interesting to read about the manufacturer of the Henderson 
 foot pump and other possible sources.  I've been surprised at 
 how expensive the pump is, compared to $50-80 for most 
 similar pumps with levers in the West Marine catalog.  Is there 
 a spring or some other mechanism to return the diaphram 
 after it has been pressed with the foot?  It doesn't seem that 
 would justify such a high price.  I have a couple of questions 
 about the pump: Does the pump hold water in it after 
 pumping?  What sort of check valves and thru-hull fittings are 
 needed or recommended?  Any comments about placement 
 and installation of the thru-hull?  What are the dimensions of 
 the pump, including the foot pedal?  Can you supply a phone 
 number or address for Fawcett's?  Thanks for the information.
 ***************************************************************************
 Lots of good questions, Bob.  

For how it works, see Chuck Holst's explanation in a response posted today.
It's really pretty simple --- two valves, diaphragm moves water in on the "up"
stroke, out on the "down" stroke.  Or "back" and "forward" with a spring
assisted foot pump; the spring provides the "up" or "back" component.  A
little water remains in the pump body, but it's only a trace, since most will
leak back down the intake hose when the system relaxes.  There are no other
check valves in most systems; there's enough pressure inside the pump to lock
out any significant amount of water coming in the through-hull fitting when
rolling or bracing, and you want to have the overboard fitting located high on
the side of the boat or on the deck.

To get a sense of size, check <www.whale.ltd.uk> and look at the "Urchin"; it
will look very similar to the Henderson "Chimp Mk1" deck pumps typically
installed on Brit boats.  Same footprint but a little higher than the
Henderson, possibly a little higher in volume of output, and it has fittings
for a 1.5" or 1.0" hose, making the whole assembly a little larger and maybe a
bit harder to fit into a kayak --- but only with the very lowest volume boats.
(It would fit in either my VCP Pintail or in the CLC North Bay I'm building if
I angled it at about 45 degrees on the bulkhead, so it should fit virtually
anything else.) The Henderson foot pump is essentially a deck pump with the
handle brackets cut off and a spring added, with a small pedal --- imagine a
nominal 3.0" disk of quarter inch plywood --- attached to the shaft with
brackets or a thicker disk simply added to the top fitting on the pump.  Ain't
rocket science, and the placement of the pump and the volume of the boat in
which it's installed will dictate what kind and size of pedal you want to
install.

Therefore, the $64K question --- or the $229 question: why does it cost so
much?  Because.  Because that's what the market will bear, apparently.  

I'm in the process of working with several people to find out the Henderson
part number for the spring; these things can be ordered through boating supply
shops --- "chandlers" in an earlier (and apparently confusing) post --- who
deal with Whale and/or Henderson.  As soon as I have the part number (and
ordered a couple for myself!) I'll post it here.  My <guess> is that that same
sping could also be used to convert a Whale "Urchin" --- generally available
at Boats'r'Us type places for around $40 --- to a foot pump for under $50.

Fawcett's in Annapolis is not the only place in the world that sells Whale or
Henderson --- but they're a local, independent chandler in Annapolis, and have
been in business there for over 50 years, and I like to support them.  They
have a web site, <www.fawcettboat.com> but they're not in the "mail order"
business, per se.  Would appreciate it if we could hold off on asking them too
much on this issue --- they're helping me on this now --- until I get
something back on the list.  Tomorrow.  Promise!  As a backup, there have to
be spring makers or suppliers out there that can build a salt-water proof
heavy duty expansion spring --- guessing the guage is about eight --- built in
a truncated conical shape (a waffle cone for ice cream lovers) with a base of
about 3.5" o/d, a top about 1.5" o/d, and about 4.0" high.

Ideas on this last bit?

Jack Martin
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