[Rhodes22-list] Compress repair and addition of compression post

[David Culp]

Mike:

To answer your questions:

Yes, from what I can tell, the boat was manufactured with the two forward
opening hatches and they were factory installed.

Yes, always been an IMF from everything I can tell.

I can find no water intrusion from either hatch.  There is no soft deck feel
anywhere, specifically around the hatches.

The mast step is secured to the deck-top atop a glassed-in block secured by
only three screws.  My understanding is that this is engineered on purpose
so that if you do hit an obstruction the screws breakaway instead of
damaging the cabin top.  There is absolutely no sign that these screws have
ever been pulled out or replaced. The IMF mast I own has never hit anything.
 There is no sign of damage anywhere on it and it is perfectly true.  I am
sure you have seen bent masts before as have I and you can never get them
back perfectly like this one is.

There is no repetitive motion or other hardware issue exerting force on the
area.  I always insure that I loosen the back stays and take that pressure
off the mast step when not in use.

I may pull a hatch and just look to see if there is any damage in the core-I
don't know if I will be able to see anything looking in between the top and
the liner but the hatches will need to be re-bedded sometime anyway.  I just
hate to mess with something that is not leaking.  If it ain't broke, don't
fix it and just go sailing.

I'm not an engineer but I'll tell you what I think.  I don't think there is
anything wrong with the design of the boat including having the hatches cut
into the cabin top.  There are too many of them out there sailing just fine
with no problems.  I think that perhaps the back stays have been
over-tensioned over the years and/or left fully tensioned while the boat was
slipped or dry sailed.  I think this is a no-no on this boat because the
forestay is slack unless you tension it up with the back stays.  And when
the boat is slipped, there is no wind in the jib to offset the back stays.
 Conversely, the other stays are offset by their opposite side stay.  So
there is still a lot of force from the sides on the mast but you don't have
the lever effect like you do on the back stays; and the cabin top is not
normally supported behind the bulkhead, so you have a big lever with nothing
opposing it (with the jib furled) or supporting it and it's pulling the mast
back and down.  I always make sure that the tension is off the back stays
when not sailing.

Let's hope this was the problem and not water damage.  There is
an explanation and I will get there even through process of elimination if
need be.  In the meantime, it is solid as a rock now.

David









Date: Fri, 6 Feb 2009 08:40:00 -0500
From: "Michael D. Weisner" <mweisner at ebsmed.com>
Subject: Re: [Rhodes22-list] Compression Repair and Addition of
       CompressionPost
To: "The Rhodes 22 Email List" <rhodes22-list at rhodes22.org>
Message-ID: <EA210ECAE9DE458EAE3DBF3F621ECC92 at D9X7C761>
Content-Type: text/plain; charset="iso-8859-1"

David,

I keep looking at your photos for an explanation and I believe that the
cause of the failure may be documented in the photo labeled "shimpost.jpg"
from your website (see attached photo.)  The more I think about it, the more
I am inclined to think that it is a failure of the deck structure.  Your
boat has two hatches, one either side of the mast, with a small ribbon of
deck between them to support the mast.  It appears to be no wider than about
a foot and the mast is offset about a foot towards the stern from the
support column.  This transfers all of the mast load (static and dynamic) to
this small portion of deck material.  I wonder if the load exceeded the
capability of the deck materials, without a plate to spread the load.  Your
solution to add another column achieves a bridge effect, bolstering the
weakened ability of the deck to carry a substantial load.

The questions are: Was the boat manufactured this way?  Were the hatches
factory installed?  Was the mast always IMF?  Did water intrusion into the
deck, possibly from a leak near the hatches, compromise the deck load
bearing ability?  Was the mast overloaded due to collision with a fixed
object or overtensioning of the stays?  Is the hardware attached to the mast
(furling genny or IMF) affixed improperly or damaged creating a repetitive
motion (excessive movement and noise while at anchor) able to drive the mast
(hammer) into the cabin top?

Mike
s/v Shanghaid'd Summer ('81)
      Nissequogue River, NY

From: "David Culp" Friday, February 06, 2009 12:55 AM
> Mike:
> Yes, we made a through examination of everything we could and everything
> else appears normal  The bulkhead which normally supports the cabin roof
> has
> not moved-what happened is that the cabin roof was bending downward behind
> the bulkhead and the roof liner was being crushed in by the rear edge of
> the
> bulkhead.  Once we flexed the cabin top up back into its proper position,
> it
> was this crushed indention that had to be filled with the shims, otherwise
> the weight of the mast would only be borne by the cabin-top structure and
> the new post.  I think we fixed it, but I would like to know what caused
> this in the first place.
>
> David
>
>
>
> From: "Michael D. Weisner" <mweisner at ebsmed.com>
> Subject: Re: [Rhodes22-list] Compression Repair and Addition of
>       Compression     Post
> To: "The Rhodes 22 Email List" <rhodes22-list at rhodes22.org>
> Message-ID: <013367FE3C614147A443FDDE0AD33C7A at D9X7C761>
> Content-Type: text/plain; format=flowed; charset="iso-8859-1";
>       reply-type=original
>
> David,
>
> Nice job!  This appears to be a good solution to the problem that has
> plagued you since you bought the boat.  I understand your statement "the
> hand tight shrouds match correspondingly in tension and length from the
> chain-plates for the first time since I've owned the boat. (The port
> shrouds
> were always a slight bit shorter)"  These observations are usually a good
> clue to something being "not quite right" structurally.
>
> Did the yard check the structure below the floor?  On these older boats,
> it
> has been common for the stringers to compress under load due to water
> damage
> in the forward area of the cabin bilge, permitting the cabin sole to sag,
> particularly if the boat was stored on the trailer with the bow lower than
> the stern permitting rainwater accumulation in this area.
>
> Mike
> s/v Shanghaid'd Summer ('81)
>      Nissequogue River, NY
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