[PUP] PPM in general - what should it be ?

[Alan Wagner]

o;?
Although an interesting concept -- I tend to agree with Ken that there is no
perfect passagemaker; at least there is no perfect passagemaker for a group
as large and diverse as this list.  I am also a little troubled by the
emphasis on "cheap," but I assume that you really mean inexpensive -- but
even that is something oftentimes in the eye of the beholder.

If you were going to pursue any meaningful PPM discussion  I think that you
would need to travel on at least a couple of different paths, defined by
whether this is a cruising couple (retired; full time live aboard; still
working; "young;" taking a couple of years off and combinations thereof)
and a general total budget (500k; 1M).  Of course that would take us down
several different paths and quickly become unmanageable.

Let's face it, the "needs" and rational "wants" of a couple that plan to
retire and live aboard while cruising the world are far different than those
of a young couple that plan to take a year or two to cruise and then return
to the "normal" world.  The calculus is also far different between a couple
and a single male.

When I started designing our current build, Michael Kasten first had us try
to decide what we absolutely wanted out of the boat, what we would like, how
we planned to use the boat and for how long.  We then had to decide a
general, very broad price range.  These generated an approximate size and
much of our layout and equipment needs.  The fine tuning was a series of
compromises and tradeoffs, with the cost gorilla always lurking over each
decision.  For example, we have two kids of different genders and it was
very important for Debbie and I to make sure that the boat had three
separate sleeping areas so that the kids could always visit for holidays
regardless of where we were.  We absolutely insisted on a covered aft deck
area, that we have enjoyed immensely on our '78 Gulfstar.  To us, those
design "musts" took precedent over almost every other competing aspects of
the design.  To others, these would be a meaningless waste of space.

All along the way there were cost and "gizmo" tradeoffs.  Our decision to
have twin keels and paravanes was influenced, in some measure, by the cost
of active stabilizers as opposed to the passive method.  Also, we were
worried about the long-term reliability of active stabilizers and the spotty
performance during the Nordhavn North Atlantic Rally pushed us away from the
more complex technology and toward the simpler and less expensive means of
roll stabilization.

Arild is correct, also, that designs have a natural time lapse and
technology marches forward even after your design decision has been made.
The reliability of active stabilizers has improved greatly since the NAR and
that was probably a significant learning event for the builders and the
stabilizer manufacturers.  Our decision to use twin keels had long since
been, however (truth be told, though, I still think I would have shied away
from the extra expense and additional complexity).

Now, it ain't over with the design either.

I will never forget my first visit to YachtSmiths International -- who we
eventually selected to build our dream -- when Brian Smyth (one of the two
guys that runs YS) told me that there would undoubtedly be changes along the
way as the boat went from 2D drawings to 3D metal, wood, glass and equipment
  I confess I did not believe him, but he turned out to be quite correct.
Once the boat begins to take shape and you start climbing on and in it,
suddenly little design alterations that never occurred to you appear out of
thin air and, sometimes, what looked great on paper doesn't seem to be what
you envisioned initially.  Being in the space can be quite different than
simply imagining it.  A good. Flexible and imaginative builder is an
absolute must.

Truth be told, you would be hard pressed to start designing a group PPM with
a specific cost figure.  Kasten could really only give us general guidelines
and said that it would really need to await submission of the plans to
builders to get their cost estimates.  Even then, when we solicited bids,
the results varied widely, by 80+ percent.

For Debbie and I, we wanted something that was safe at sea, could handle a
long passage, and had systems that leaned toward the simple and easy to
repair as opposed to the more complex and difficult to repair.  We also
wanted some measure of luxury as well.  I know that many can live without
air conditioning at night.  My hat is off to you, but here in Florida doing
so for many many nights out of the year would make a night out on the hook
miserable.  Some like camping; we don't.  We hate the all night generator,
though, so we wanted the ability to run the air conditioner in the master
cabin overnight on battery/inverter power alone.  We ended up with a huge
battery bank (1700 amp hours @ 24v) to meet our design needs.  And dang it,
I confess that I want a TV in each stateroom and lots of speakers to play
high quality, loud music whenever I wanted to throughout the boat.  No one
needs air conditioning, flat screens, and a great sound system, but I want
the boat to be a home, not just a way to get across the Atlantic.

We chose aluminum, but steel is probably less expensive (but has a lower
resale value and must be painted).

You really have to think about how you will live on the boat -- particularly
if it will be home for 15+ years.  While there are some neat design and
efficiency reasons to have a 6:1 L/W ration, in reality I think that is
unreasonable, unless you are going to end up with a very long boat, which
will be expensive almost regardless of what you put inside.  At 6:1 L/W a 50
foot boat will only be 8.33 feet wide -- and a lot less than that below deck
  That severely restricts your living space and its usability, especially if
the boat is intended as your long term home and not just a mechanism to take
a year cruise.  You would need a 72' boat just to get a 12 foot beam.

We are probably better off discussing systems as opposed to the perfect boat
  Any systems discussion will allow anyone thinking about a build, purchase,
or major refit to decide how any particular design feature will fit into
their concept of a perfect passagemaker.  There can be more than one PPM,
after all.

By the way -- no small part of what will be our PPM was the result of input
from the T&T list (our initial design predates PUP).  Heck, in the end, I
owe the electrical design for our PPM to Arild, who I eventually hired to
fine tune what Kasten originally specified.  Arild, of course, came right
from our midsts.  The T&T forum and now PUP has been, and continues to be, a
huge resource for me, even now, as my systems are finalized.  As such, I
suspect that if anyone is in the same "what do I design/build" stage that I
was in a four years ago, a discussion of passagemaker systems could only
help.


Alan Wagner
Building 53' Aluminum Passagemaker
Kasten designed / YachtSmiths Built

-------Original Message-------

From: hannu venermo
Date: 12/7/2008 2:43:49 AM
To: passagemaking-under-power at lists.samurai.com
Subject: Re: [PUP] PPM in general - what should it be ?



This makes a PPM;
-------------------------------------------------
6:1 L/W ratio
Heavy
Standardisation in mechanical engineering.
Steel
Redundancy in mechanical aspects as much as practical
All components are extremely fit for purpose and chosen for long-term
reliability and capacity