I am doing a complete interior on my Rhodes 22. The V-berth cushions
are next on my list. I was considering the use of approximately 3/8 plywood
as a backing for the two cushions that go up there. Is that the proper size?
Exactly what IS "marine-grade" plywood. Can I use a decent grade plywood
and apply a finish to it for protection? Where do I buy "marine-grade"
plywood. (Hint: Home Depot ain't it.) How about stainless steel
staples? Where can I get them?
Most of all, what is it that I am NOT asking that I should be asking
about this phase of the project?
Thanks.
Bob Hendrickson
19 Apr 2002
You want to specify marine grade plywood grade A/A or A/B. Marine grade
means the wood has been pressure treated with wood preservatives to render
it insect & rot resistant + the glue used to hold the laminations together
is waterproof. The grade refers to the number of allowable defects such as
voids and repaired "plugs". A/A means the best grade on both sides, but is
also the most expensive & least available. Grade A/B allows slightly more
imperfections on the backside, which won't be seen & it is cheaper & more
available. The next grade down from marine grade is exterior grade which is
not appropriate for use on a boat. I used 1/2" thick marine grade plywood
grade A/B when I redid my V-berth sole. A good lumber yard like Wickes or
Carter's should be able to order the marine grade plywood for you. Note
that you will need two full sheets & even grade A/B ain't cheap! A boat
repair yard should be able to order it as well.
Are you going to make a new V-berth sole or attach the plywood to the
bottoms of the V-berth cushions with staples as per the original cushions?
When I ordered new interior cushions from GBI, they came without any plywood
backing. So, I had to make a permanent V-berth sole.
I used my original V-berth cushions as a pattern to cut the plywood. I made
my V-berth sole in 2 halves split longitudinally along the centerline. I
joined the two halves with a 72" stainless steel piano hinge & stainless
flat head wood screws. Each wood screw was glued in with waterproof wood
glue. The companionway hatch is just barely large enough to allow the
folded V-berth sole to fit thru it. Then, as you pass by the mast
compression post, allow the two halves of the V-berth sole to start
unfolding like the wings of a butterfly.
WARNING: be careful to not have any body pieces/parts near the backside of
the hinged joint as you set it into place - it can pinch with incredible
force as the two halves spring open. Being on center, the backside of the
joint is the most balanced point to be holding the piece, but keep your
hands & fingers out of there!
The V-berth sole is a very wierd shape. You may have to test fit the
V-berth sole several times to get a good fit. I used an orbital palm sander
to trim the plywood to fit.
You will also need a couple of hatches in the new V-berth sole in order to
be able to get access to the storage area on the aft end of the V-berth. I
used a pair of 12" stainless steel piano hinges & more of those stainless
flat head wood screws & waterproof glue.
The final finish on your new V-berth sole is up to you. I used an exterior
grade oil base gloss white enamel. Most of the time, the V-berth sole isn't
visible under the cushions, so I didn't want to bother with staining &
varnishing. The gloss white finish seals the surface, is mildew resistant,
cleans up easily, & kind of looks like the cabin liner when you do lift up a
V-berth cushion.
Monel staples are available Defender Marine or WEST Marine. Monel is an
alloy of copper & nickel that was specifically developed for corrosion
resistance to sea water. In sea water, monel is even more corrosion
resistant than 316 SS.
Roger Pihlaja
S/V Dynamic Equilibrium
19 Apr 2002
Marine grade plywood is constructed with glues that are moisture and rot
resistant. Note: not water proof, but better than most.
Stainless steel staples are available from West Marine.
The plywood can be ordered special through Home Depot or Lowe's or any lumber
yard. You just need to get someone that knows what it is and is willing to do
the work for you. My V-Berth cushions are the original factory cushions and
do not have any plywood in them.
Rummy
19 Apr 2002
One other thing about Marine grade plywood, it will have no voids that might
hold water, comes into play when used as hull sheeting, that what really
drives up the price because every layer is like a finish layer, normail
plywood will have void on the inner sheets (i.e. knots voids), they can only
be seen when the plywood is cut. on the marine stuff they will fill then
just like the surface.
MJM
19 Apr 2002
Dynamic Equilibrium is also a 1976 Rhodes 22. The floatation foam under my
V-berth stops about 14" forward of the V-berth bulkhead all the way across
the width of the hull. Most of that 14" of space between the foam & the
bulkhead is taken up by the rectangular 15 gal fresh water tank. However,
there is an oddly shaped, but still useful storage area to port & starboard
of the water tank. These are the storage areas I provided access hatches
for in my new V-berth sole. On my boat, the ship's battery & 120 VAC/12 VDC
charger takes up most of the storage space on the port side of the water
tank. So, the access hatch on the port side is sized & located to allow
good access to the battery. To the best of my knowledge, this is the OEM
factory stock arrangement for the floatation foam & fresh water tank for
that year.
Roger Pihlaja
S/V Dynamic Equilibrium
19 Apr 2002
Kathy and I did the same to the "NoKaOi"; however, we did not go to
Roger's extent. I have the marine grade plywood in two sections and merely
slide them apart (stack the cushions on top of each other and then lift half
of the plywood panel up) when I need to get to the batteries. Roger's
solution is probably a bit ealier on getting to the batteries but I have two
left hands so cutting the openings would be a challenge for me.
The panels probably add a bit of weight to the boat but as we just like
cruising around it is not a big deal. Every now and then when we find
another boat on the water we do our darnest to beat them. Sometime we do
and sometimes we don't.
Bob and Kathy on the "NoKaOi"
19 Apr 2002
I checked my paperwork and, indeed, mine is a 1976, also. I have created
a webpage with some photos of my project so you can see. The first photo is
the area we are talking about. The address of the webpage is:
http://home.earthlink.net/~rhendy
Check it out.
Also, why did you need to use TWO full sheets of plywood? I assume we are
talking about 4X8 sheets. "Spooning the two pieces together looks like an
easy fit onto a 4X8 space.
Bob Hendrickson
20 Apr 2002
As I recall, it was close, but I couldn't quite get the two halves of the
V-berth sole to fit on one 4' X 8' sheet of plywood no matter how I layed
them out. If your's will fit, then count your blessings.
As I look at your 2nd photo, your water tank is held in place by the foam.
My foam stops at the forward end of the water tank, thus leaving an open
storage area between the foam & the partial bulkhead. My water tank is
retained by a nylon strap which goes around the tank lengthwise & anchors
the tank to a pair of molded-in fiberglass stringers attached to the hull
under the tank. The water tank itself looks like it's about the same size &
shape as mine. The partial bulkhead at the aft end of the V-berth looks the
same.
Roger Pihlaja
S/V Dynamic Equilibrium
21 Apr 2002
Can you help me out. I am getting to the point of replacing the v-berth in
my boat. My boat is a 1974 version and had a fiberglass insert that I
removed. There was about 3 garbage bags of small peices of foam about 1 to
2 inch chunks under it. I now have a 1/2 inch marine grade plywood bulkhead
epoxied in place in front of the large peice of cement ballast. From there
forward there is nothing but the inside of the hull. I need to put some
structure there to put a v-berth sole on. The back of the seats rest on a
3 inch peice of plywood that is epoxied to the inner hull. I was wondering
if something like that is what your v-berth sole rests on, and what other
structure may be involved. My v-berth will be 4 inches lower than normal
but if you could help me with a general idea on how your 1976 v-berth is
constructed it would be a big help to me. if you get some free time I could
use the help. I am in the process of finishing up the seats and flooring
and will be moving to the v-berth next.
I thank you for all the past help you have given me and others.
Denny
1974 R22 Gossamer Wing
Berwick, PA
20 Apr 2002
Are you planning to have cushions in your V-berth? If so, are you planning
to custom sew them yourself or hire someone to do the job? The reason I ask
is because if you make the V-berth 4" lower than stock, then the factory
cushions will not fit. Take a look at how the hull tapers vertically in the
V-berth area. The result of this taper is that the width of the V-berth at
a vertical position 4" lower than stock is probably 1-2" narrower than the
factory stock V-berth & the stock cushions will not fit. You might not fit
very well either as the length of the lowered V-berth will also be reduced
from stock due to the stem angle on the bow.
On Dynamic Equilibrium, the forward end of the port side settee is the
partial bulkhead that defines the aft end of the V-berth. That partial
bulkhead & the V-berth sole are the only wooden structures in the V-berth.
Most of the V-berth is supported by pour-in-place polyurethane foam. Look
on P 56 of the 2002 Defender Marine Buyer's Guide. Defender will sell you
2-part pour-in-place polyurethane floatation foam in up to 10 gal quantities
(actually two 5 gal pails). 10 gal of premix would yield about 48 cubic
feet of foam.
You might consider asking Stan to sell you the plywood interior
pieces/parts. You might have to do some custom trimming to get everything
to fit properly, but I'm sure the factory could provide you with
pieces/parts that will be close.
Other than that, I'm not certain how to help you. If you are planning an
interior radically different from stock, then you'd better get out your
calculator, tape measure, & drafting board because you've taken on quite a
project! You will find there isn't a single straight line &/or right angle
in the entire interior & every single piece will have to be custom fit.
Seriously, I'm not quite sure what to advise you. If you could phrase your
questions more specifically, then maybe I'll be able to help.
Roger Pihlaja
S/V Dynamic Equilibrium
20 Apr 2002
Thanks for the quick response. You are right on target as usual. I will
answer your questions as best I can. Yes I plan to have cushions in the
v-berth and am aware that they will need to be custom made. These may have
to wait until after I get the boat in the water and sailing. I agree that
there aren't any straight lines and I used a laser level to spot a reference
line around the inside of the cabin to work from. I have talked to Stan
about floatation and he said they use foam blocks now, and didn't think it
would be a good idea to try them in a boat this old. I guess my question in
this area is, do you think that the sides of the hull need to be reinforced
side to side. Your foam floatation may do this and the original fiberglass
insert in my boat may have helped stiffen it some before it broke loose. If
this isn't a problem and I can just put two boards in from the bulkhead to
the bow and put a plywood sole over it without epoxying the sides fast, my
job is relatively simple. I have changed the interior not because I'm that
smart but because I didn't have a lot to work with and this is my first
attempt to do any kind of boat work. This is like school, I'm learning all
the time. I hope to get to meet you someday and check Dynamic Equilibrium
out, and thank you personally for your help.
Denny
20 APR 2002
Hmmm, does the hull need to be reinforced up in the V-berth area where the
pour-in-place foam goes? I have two comments. 1st, I have never had my
bow floatation foam out, so I don't know if there is any additional
reinforcing embedded in the foam. Kind of makes you wish for X-ray vision, doesn't
it?
2nd, that "original fiberglass insert" must have had some function beyond
annoying you while getting it out. If you press hard on the sides of the
hull up in the V-berth area, can you observe any deflection or "oil
canning"? You might need an assistant for this experiment. Tell me more
about this "original fiberglass insert". A picture or a drawing would
help.
The pour-in-place foam will definitely help to stiffen things up & tie the
whole structure together. However, I'm hesitant to recommend you do that
without installing some structure designed to replace the "original
fiberglass insert" until I completely understand what that piece was
supposed to be doing. Sailing close hauled, crashing thru waves, the bow
area is subject to some incredible pounding. If you collide with
something in the water, like say a floating log, the bow area is the most likely
place to take the hit. We don't want the structure to wimp out. Question, how
does the height of your lowered V-berth compare with the height of the
waterline? I would think we would want the pour-in-place foam to come up
the hull to a point well above the waterline if we are going to depend
upon it for reinforcing. You might not think -4" would be a big deal, but
consider this:
The maximum deflection of a beam supported on the ends & loaded in the
middle is proportional to the unsupported length of the beam raised to the
3rd power. I haven't made any measurements, but let's just say there's
24" between the stock V-berth sole & the bottom of the foredeck & you are
proposing to increase that to 28". So, all else being equal, the
approximate stiffness of the hull above your new V-berth will be: [(24)^3
/ (28)^3] * 100 = 63% of the original stiffness due to the increased
unsupported length. Or, to put it another way, your hull will deflect
about 37% more than mine will if we hit the same object in the water!
Are you getting some sense of what you might be getting into here? This
is one reason why naval architects earn their big bucks.
Roger Pihlaja
S/V Dynamic Equilibrium
21 Apr 2002
I will try to answer your questions and add some measurements this time.
Does the hull deflect? Yes, if I hold on to the deck and put my knee against
the hull around 4 inches above the water line I can get the hull to deflect
enough that the old bottom paint crackles some. It takes a lot of effort to
do this. It is not as solid as the mid and aft sections of the boat but
there is more of a rolled or rounded affect in those areas. I don't know how
to get you a picture of the v-berth insert unless I would take a picture and
send it to you. I'm not a computer guru like some on the list. I think I can
explain it to you. First, if you would take what you call the partial
bulkhead that is plywood on your boat and think of it as a piece of 1/8
laminated fiberglass that runs straight across side to side and is 21 1/2
inches high at the center line of the boat, that would be the aft section of
the v-berth. Then think of your v-berth sole you have made of plywood as
another 1/8 piece of fiberglass molded to the aft piece. The edges are
flared up about a inch as an area to glue to the sides. The only things
other than that is it has a 10 gallon water tank molded in the center at the
bulkhead end, and 3 half round stiffeners under the sole side. I believe
this unit was made to be installed on top of a foam block because it isn't
that rigid and it looked to me that it had broken loose from the sides on
many occasions. The big problem with it is that it is one piece and you
can't get under it to work on anything. It may be that it was a idea that
didn't work out and they discontinued it. I can only wonder what it was like
originally and what may have happened. All that said, this boat was moored
in Lewis Harbor, Hyannis Port,Mass and sailed in Nantucket Sound not what I
would call light water, regardless that doesn't make it safe or right.
As for the height above the water line of the lowered v-berth, I put a light
on the inside with a block of wood at the sole height and went outside and
it measured around 7 1/2 to 8 inches above the bottom of the red stripe
around the boat. I have a measurement you could check with your boat. If you
would make a parallel line 2 inches above the height of your port seats
(without cushions) and extend it forward it would be the height of my
v-berth sole. It may not be 4 inches low. I have been trying to avoid
pouring foam because I really don't know how this stuff works, but I might
not have a choice. Have you ever checked out www.jamestowndistributors.com
out, they have a polyurethane 2 part foam for $70.20 a 2 gallon kit to fill
8 cu. ft.. They also have a lot of wood working and boating supplies at good
prices. Is this the same stuff you were speaking about?
I may well have ask you some unanswerable questions but if you have any
insights on these matters I would be interested in any information you would
care to share. Thanks again.
Denny
21 Apr 2002
Lot's of boats have molded-in fiberglass interiors. The concept allows
large portions of the interior to be installed in one very fast & efficient
operation. The molded surfaces are waterproof, easy to clean, & won't rot.
The cabin headliner on our Rhodes 22's is another example of this strategy.
The disadvantage of the molded interior pieces/parts is that they tend to
make the interior look very monochromatic (i.e. the "Clorox Bottle" look),
are very difficult to change or customize, and tend to restrict access to
critical structures for inspection &/or maintainence. I wasn't aware that
GBI had experimented with molded-in V-berth's.
The molded-in interior pieces/parts were probably attached to the hull
before the deck was set into place. Usually, the molded-in interior parts
have a glue tab around the perimeter. The piece is glued to the interior of
the hull by applying epoxy resin to this tab &, quite often, one of more
layers of fiberglass tape are applied over the joint to waterproof it, hide
it, & strengthen it. This entire process is called tabbing. In the case of
your Rhodes 22, it sounds like the tabbing joint had failed in one or more
places.
If the laminate thickness in the V-berth sole area is really only about
1/8", then there certainly should have been some sort of support underneath
it. Fiberglass is the least strong when it is being flexed. If there
wasn't any molded-in floatation foam or some other structure under the
V-berth sole to prevent this flexing, then this may be the primary reason
why the tabbing joint failed prematurely. Do you find any "spider cracks"
in the gel coat of the V-berth sole that you removed, particularly around
the area of the tabbing? If so, then that is diagnostic of excessive
flexing.
I just went out & tried the same experiment in hull flexing you described.
My hull is so rigid it's like pushing on a concrete sidewalk! It doesn't
flex a bit in that area.
The 2-part floatation foam from Jametown Distributers sounds like the
correct product for this application. I don't see how you are going to not
be able to use something like that at this point. I'm pretty certain the
fiberglass laminate in the hull was also designed to be backed up by foam in
that area & won't be sufficiently rigid without it. The pour-in-place
polyurethane foam products are not difficult to use. Just read & follow all
the directions & safety precautions that will come packaged with the kit.
You have several options. You can install the original fiberglass V-berth
pieces/parts back into their original locations, making sure they are tabbed
securely to the hull all around & fill the void space underneath with
pour-in-place foam. Or, you can probably purchase a 1976 pattern V-berth
partial bulkhead & V-berth sole from GBI & fill in the void space with foam.
Or, you could build the V-berth partial bulkhead & V-berth sole yourself
from scratch either from plywood or fiberglass panels, again finishing up
with foam filling. There is also a polymer laminate product called
"Starboard" that is sold in sheets sufficiently thick & large enough for
this project. You might consider using Starboard laminate instead of
plywood, but you will still have to fill in underneath with foam.
Good Luck!
Roger Pihlaja
S/V Dynamic EQuilibrium
21 Apr 2002
