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From: Doug Lloyd <dlloyd_at_telus.net>
subject: [Paddlewise] Plastic Bulkheads
Date: Tue, 18 Jan 2000 21:30:56 -0800
You said:
<snip>
>> I'm getting ready to remove my forward bulkhead and replace it with a
plywood
bulkhead to facilitate mounting a foot pump.>>

Don't do it. I've seen a British-heavy deform around the bulkheaded area,
after someone installed a ply bulkhead as a replacement for foam. The ply
was well sealed, but still swelled. It also. in general, expands and
contracts at a different rate than the fiberglass. dave Kruger mentioned
something along these lines too. My suggestion? Use the ply now as a
template. Get the fit just right, then wax it, and lay-up a fiberglass
bulkhead on top. Put in a "real" bulkhead, Woody, not a wooden one (wood is
good with wooden boats, though).

BC'in Ya
Doug lloyd (who is being hired this year to remove the botched bulkhead
above from a friend's kayak) 
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From: David Seng <David_at_wainet.com>
subject: RE: [Paddlewise] Plastic Bulkheads
Date: Tue, 18 Jan 2000 16:09:05 -0900
> -----Original Message-----
> From: Robert Woodard [mailto:woodardr_at_tidalwave.net]
> Sent: Tuesday, January 18, 2000 3:02 PM
> 
> My apologies for not remembering who told me this, but 
> someone here told me
> they had removed the plastic bulkheads in their fiberglass kayak. I'm
> getting ready to remove my forward bulkhead and replace it 
> with a plywood
> bulkhead to facilitate mounting a foot pump. I'd appreciate 
> any lessons
> learned on getting the old plastic bulkhead out.
> 
> Thanks in advance,
> 
> Woody
> 

Woody,

  I'm wondering why you want to remove the existing bulkhead (I'm assuming
that it's watertight).  Couldn't you simply "beef up" the existing bulkhead
by epoxying and glassing the plywood into place directly behind the existing
bulkhead, or would that place the new plywood bulkhead too close to your
feet? (with a 28'inseam my short legs don't have problems like this<g>).
You probably can't epoxy anything to the bulkhead itself, but I'd think that
you would be able to push the plywood up tight against the plastic bulkhead
and then use an epoxy paste to create a fillet joint between the epoxied
plywood and the hull/deck.  Then use some 1.5" or 2" tape and glass in a
couple of layers over the fillet.

Dave Seng
Juneau, Alaska
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From: Robert Woodard <woodardr_at_tidalwave.net>
subject: RE: [Paddlewise] Plastic Bulkheads
Date: Tue, 18 Jan 2000 20:45:48 -0500
>   I'm wondering why you want to remove the existing bulkhead (I'm assuming
> that it's watertight).  Couldn't you simply "beef up" the
> existing bulkhead
<snip>

Thanks Dave. That was my original intent, but after I got the plywood cut to
size I started to worry that the space between the plastic and wood bulkhead
would be a potential place for water to gather and sit, especially since the
plastic bulkhead has a pin hole in it to balance the air pressure from the
forward hatch.

Another reason is I thought the bulkhead would be much stronger if I could
glass the seam tape on both sides of the bulkhead. The plywood may give a
better place to mount the pump screws and washers (they would have to
contact the plastic bulkhead if not removed).

Bad idea? Good idea?

Woody


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From: Dave Kruger <dkruger_at_pacifier.com>
subject: Re: [Paddlewise] Plastic Bulkheads
Date: Tue, 18 Jan 2000 18:20:31 -0800
Robert Woodard wrote:
> 
> >   I'm wondering why you want to remove the existing bulkhead (I'm assuming
> > that it's watertight).  Couldn't you simply "beef up" the existing bulkhead
> <snip>
> 
> [snip] I thought the bulkhead would be much stronger if I could
> glass the seam tape on both sides of the bulkhead. The plywood may give a
> better place to mount the pump screws and washers (they would have to
> contact the plastic bulkhead if not removed).
> 
> Bad idea? Good idea?

Small caveat about installing a (rigid) plywood bulkhead inside a glass boat: 
because the hull (and deck) flex under load -- even at the bulkhead locations
-- most mfrs use a bulkhead material which can stretch or compress.  Mine have
bluefoam bulkheads.  Strong enough for my uses, but unfortunately not strong
enough for a pump installation.  This reduces the chance that the seal around
the bulkhead (to the inner hull/deck surfaces) will fail when the hull
"breathes."

Mind you, I am offering the following in complete ignorance, having never tried
what you are up to, but:  you may need to surround the plywood with a 2-inch by
2-inch "collar" of minicell or somesuch to provide the flex needed.  Being that
dimension, the minicell should be able to withstand the lateral forces your
pump arrangement will generate when you activate it.

I bet Matt Broze knows what is best to do here.

-- 
Dave Kruger
Astoria, OR
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From: CA Kayaker <cakayak_at_mindspring.com>
subject: [Paddlewise] Plastic Bulkheads - DONT Cut Yet
Date: Tue, 18 Jan 2000 18:59:19 -0800
A thought.

Instead of replacing the bulk head with a plywood one or simply placing the 
plywood over the existing think about this:   How about taking a thin piece 
of closed cell foam with the diameter cut to squeeze in tightly and with 
some glue to hold it in place.  You are set  - determine what thickness 
foam would give you the ability to install the plywood and the pump with 
sufficient room for the pump to clear your pegs/foot pedals.   You don't 
loose the original bulk head and you gain a surface to mount the pump to 
and have a means of absorbing and distributing the force of using the pump 
without damaging the original bulk head.

Ca Kayak
Fred


to it At 08:45 PM 1/18/2000 -0500, you wrote:
> >   I'm wondering why you want to remove the existing bulkhead (I'm assuming
> > that it's watertight).  Couldn't you simply "beef up" the
> > existing bulkhead
><snip>
>
>Thanks Dave. That was my original intent, but after I got the plywood cut to
>size I started to worry that the space between the plastic and wood bulkhead
>would be a potential place for water to gather and sit, especially since the
>plastic bulkhead has a pin hole in it to balance the air pressure from the
>forward hatch.
>
>Another reason is I thought the bulkhead would be much stronger if I could
>glass the seam tape on both sides of the bulkhead. The plywood may give a
>better place to mount the pump screws and washers (they would have to
>contact the plastic bulkhead if not removed).
>
>Bad idea? Good idea?
>
>Woody
>
>
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From: Robert C. Cline <rccline_at_swbell.net>
subject: Re: [Paddlewise] Plastic Bulkheads
Date: Tue, 18 Jan 2000 21:57:54 -0600
David:

I have a shortened cockpit.  My idea about installing a foot pump is to cut
a hole in the forward bulk head and mount the footpump behind the bulkhead
with the pump jutting out into the cockpit, and glass up behind the bulkhead
to seal the pump in.

Can't you glass onto glass?

Robert

David Seng wrote:

> You probably can't epoxy anything to the bulkhead itself, but I'd think that
> you would be able to push the plywood up tight against the plastic bulkhead
> and then use an epoxy paste to create a fillet joint between the epoxied
> plywood and the hull/deck.  Then use some 1.5" or 2" tape and glass in a
> couple of layers over the fillet.
> 

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From: Bob Volin <bobvolin_at_bestweb.net>
subject: Re: [Paddlewise] Plastic Bulkheads
Date: Tue, 18 Jan 2000 22:38:41 -0500
Robert:
  Another possibility to consider....  Rather than removing or replacing
your front bulkhead, consider carving a mount for the foot pump  into 3"
minicell foam which is shaped to fit the bulkhead.  The minicell won't
present the potential for rot that you mentioned with respect to wood
against the bulkhead, and with a good fit and a little glue, it should
present a solid enough foundation for the foot pump.



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From: Erik Sprenne <sprenne_at_netnitco.net>
subject: Re: [Paddlewise] Plastic Bulkheads
Date: Tue, 18 Jan 2000 22:15:20 -0600
> > David Seng wrote:
> >   I'm wondering why you want to remove the existing bulkhead (I'm
assuming that it's watertight).  Couldn't you simply "beef up" the existing
bulkhead
> <snip>
> 
> Thanks Dave. That was my original intent, but after I got the plywood cut
to size I started to worry that the space between the plastic and wood
bulkhead would be a potential place for water to gather and sit, especially
since the plastic bulkhead has a pin hole in it to balance the air pressure
from the forward hatch.
>
> Another reason is I thought the bulkhead would be much stronger if I
could glass the seam tape on both sides of the bulkhead. The plywood may
give a better place to mount the pump screws and washers (they would have
to contact the plastic bulkhead if not removed).
> 
> Bad idea? Good idea?
> 

Caveat:  I've never done what you're planning on doing, but am willing to
offer a few brainstorming comments.

Both approaches seem workable, but I like a third one best.

Adding the wood bulkhead to the existing plastic bulkhead could have the
negatives you mention, but the positives would be that you are adding to an
already watertight bulkhead, and so don't have to be quite as persnickety
about doing the fiberglassing *just so*.  You could also fiberglass in the
plywood bulkhead only on the sides, leaving an opening (at least a crack)
on the bottom for water to drain out, while still having a solid enough
structure as a base for your pump.  I'd be leery, though, of permanently
glassing in a piece of wood that would be exposed to so much water, as it
might eventually rot - and then you'd have to "undo" the whole assembly.

If you choose to remove the plastic bulkhead, you MUST be much more careful
about doing a *good* fiberglassing job, which may be difficult given the
location of the bulkhead, and the need for you to worm your upper body into
the kayak in a very awkward position - while holding all your fiberglassing
supplies.  The inaccessability of the bulkhead position for doing the
fiberglassing (especially from the cockpit side) may be at least a part of
the reason that the manufacturer chose to use a plastic bulkhead instead of
a glassed-in (fiberglass) bulkhead.  It is also a pretty tricky
fiberglassing job to do a seam around the perimeter of a bulkhead, as many
short pieces of seam tape would probably have to be used, given the curved
contour you're trying to seal.  Should you choose to remove the plastic
bulkhead and glass in the plywood one in the same location, it would be
important to either remove all of the adhesive used to glue in the plastic
bukhead (to provide for the most solid adhesion) - which would require
*VERY* judicious use of a sander or grinder, or would require the use of
wide enough fiberglass tape to span any adhesive residues in order to
provide for a solid and watertight joint.

A possible third option.  
Since your existing bulhead ain't broke - don't 'fix' it.
And since wood - unless *totally* sealed against moisture infiltration -
sooner or later might be prone to rot, you might want to consider an option
whereby you could install a plywood pump support that can be removed fairly
easily at a later date.  

One way to do this would be to use some sort of flanges that would hold the
plywood pump-mounting plywood piece in place. Fabricating these  would
become the trickiest part of the installation, and could be done by some
creative fiberglassing work with woven roving, or as simply as screwing
wood blocks or aluminum angle brackets through (gasp!) the hull on both
sides.  The pump-mounting plywood would then be made in a hinged fashion,
using a section of brass piano hinge, so that the plywood would unfold,
with the hinge furthest aft (oriented up-and-down), and the 'wings'
spreading out and forward into place between the existing bulkhead and the
already-installed flanges (got that?).  This allows for the use of a piece
of plywood that *exactly* fits the inside of the hull next to the existing
bulkhead.  Then -- by screwing a crosspiece across the hinge (or maybe even
mounting the pump across the hinge), the folding piece of plywood would be
'locked' in the open position between the existing bulkhead and the
flanges.  The end result would be a removeable pump mounting plate for ease
of pump servicing (and wood replacement if it eventually rots) without
compromising the integrity of the existing bulkhead. This idea would
require a bit of tweaking and fine-tuning to adapt it to your boat and
pump, but it might work. 

Regards,
Erik Sprenne

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From: Michael Daly <michaeldaly_at_home.com>
subject: Re: [Paddlewise] Plastic Bulkheads
Date: Wed, 19 Jan 2000 21:54:47 -0500
Erik Sprenne wrote:

> If you choose to remove the plastic bulkhead, you MUST be much more careful
> about doing a *good* fiberglassing job, which may be difficult given the
> location of the bulkhead, and the need for you to worm your upper body into
> the kayak in a very awkward position - while holding all your fiberglassing
> supplies.

Actually, it isn't that difficult to get in there.  The forward hatch allows some
work to be done from that position.  To get in through the cockpit, I suspended
my kayak above the ground, cockpit facing down.  I could stand up inside the
cockpit and reach in to the bulkhead position.  I used a vacuum cleaner to suck
out the air and lots of lights on the outside of the hull for illumination (it's pretty
translucent with white gel coat).  It was suspended over a stairwell, so I had a
couple of stair positions to choose from depending on what I was doing.  A high
step let me reach well into the kayak, while the lower one let me work standing
straighter.

I also was able to stand the kayak on its stern in the stairwell.  This allowed me to
get in through the forward hatch with the bulkhead horizontal.  I installed the
bulkhead from the cockpit side, with a broad strip of fiberglass as a fillet, then
stood the kayak on end to do the hatch side.  I filled in the gap between the
bulkhead and hull/deck with thickened epoxy and didn't need to worry about it
running.  Another wide band of fiberglass finished it.

Putting the kayak in a horizontal, inverted position also made installing the shelf
a piece of cake.

I haven't had any problems with deformation on the hull/deck, nor water leaking.
The wood looks dry by inspection through the fiberglass.

Mike

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From: <JSpinner_at_aol.com>
subject: Re: [Paddlewise] Plastic Bulkheads
Date: Tue, 18 Jan 2000 23:17:01 EST
    I haven't a clue of what I'm talking about here but I have been toying 
with the same thing but not taking out the bulkhead. I was thinking of using 
the minicell foam, maybe 2"-3"thinck collar with the wood glassed into a deep 
channel, maybe all but the last inch, into the foam then the foam glued and 
glassed to the hull. That would allow for me to push it in really tight and 
get a form fit with very simple trimming, Question is: will that be strong 
enough for the pressure of the foot pump? If it is pushed really tightly into 
the "V" of the bow I'd think it would take the pumping pressure. If not I'm 
not really any worse off because I'll have the same resources I have now, a 
hand pump and the original bulkhead.
    What happens if water gets strapped behind it? I guess it depends on the 
placement, volume and conditions. Any suggestions on how to test what would 
happen? The space looks to be about 6" deep by about 18" diameter. I don't 
recall the math for the volume. Maybe 3 liters? Can anyone think of a way to b
uild in a safety valve to empty if it breached at the top?
    I don't need any more arm and shoulder development than I get paddling. 
Pumping is a bore. All suggestions welcome.

Joan Spinner
   * * *
Trying to stay dry on the Chesapeake Bay watershed
In a red, CD Breeze or
a yellow/white Dagger Meridian SK (if Dagger will fix the skeg!)

In a message dated 1/18/00 9:33:15 PM, dkruger_at_pacifier.com writes:

<< Small caveat about installing a (rigid) plywood bulkhead inside a glass 
boat: 
because the hull (and deck) flex under load -- even at the bulkhead locations
-- most mfrs use a bulkhead material which can stretch or compress.  Mine have
bluefoam bulkheads.  Strong enough for my uses, but unfortunately not strong
enough for a pump installation.  This reduces the chance that the seal around
the bulkhead (to the inner hull/deck surfaces) will fail when the hull
"breathes."

Mind you, I am offering the following in complete ignorance, having never 
tried
what you are up to, but:  you may need to surround the plywood with a 2-inch 
by
2-inch "collar" of minicell or somesuch to provide the flex needed.  Being 
that
dimension, the minicell should be able to withstand the lateral forces your
pump arrangement will generate when you activate it. >>

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From: <JCMARTIN43_at_aol.com>
subject: Re: [Paddlewise] Plastic Bulkheads
Date: Wed, 19 Jan 2000 07:59:24 EST
Can't remember exactly how Woody's thread started, but, from recent points, it sounds like the existing plastic bulkhead is sound and usable.  Bob Volin's and Joan Spinner's responses line up with what I was thinking originally: before you go in there to remove a viable bulkhead (it didn't sound like fun to me), consider the least invasive option, and one which gives you the greatest ability to fine tune your solution.  Assuming you have room and that you don't have foot pegs and/or rudder pegs in the way, I'd craft a minicell foam plug to fit the area at the forward end of the cockpit, making the plug a tad oversized so that it's wedged in a little, and use it as a footrest.  Then, carve out a void for the footpump body --- making it a little undersized so the pump is held in place by the foam ---, "ditches" for the intake hose and the overboard hose, and maybe contact cement a piece of epoxied plywood at the front end of the plug to spread any force created by the pump acros!
!
s the surface of the bulkhead (although that last step might not be necessary).  I wouldn't cement the plug in, though, because it would be a bear to get it out, and you don't need to.  If you cut it a little oversized to begin with, it will wedge itself into position, spreading some of the force it absorbs outward into the hull and some forward into the bulkhead; from the voice of experience, Woody, I'd definitely glue or tape in a piece of webbing across the forward end of the plug so that you have several inches of loose webbing hanging out on either side of the plug in the cockpit allowing you to pull the sucker out when/if you want to do modifications.  

Can't say that that kind of installation will last forever, but it's worked for me in the Pintail for about seven years, I guess.  Nothing is glued or fastened in --- it's all by friction, and it works.

Finally, this kind of installation gives you flexibility to move the pump location around a little, and it's easy to remove the whole deal if you want to work on the pump.  (Not sure why you would --- they last forever.)

Good luck!

Jack
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From: Chuck Holst <CHUCK_at_multitech.com>
subject: RE: [Paddlewise] Plastic Bulkheads
Date: Wed, 19 Jan 2000 10:04:02 -0600
>>
Another reason is I thought the bulkhead would be much stronger if I could
glass the seam tape on both sides of the bulkhead. The plywood may give a
better place to mount the pump screws and washers (they would have to
contact the plastic bulkhead if not removed).
>>

You might be making more work for yourself than necessary. My Romany's
fiberglass forward bulkhead has seam tape on only one side, and I have never
had a problem with it, even though my foot pump is mounted on it. And it
wasn't filleted with epoxy paste before the tape was applied, either.

Chuck Holst 
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