!!
Jeff wrote:
JimC wrote:
And let me point out again, its not the weight, its the
location. A 250 pound engine hanging off the stern contribute
far more to the pitch moment than an inboard close to the center
of the boat.
Well, that's clear enough, and I agree. But once more, the boat is
built to be balanced fore and aft with a motor and a crew in the
cockpit. And it is.
Totally irrelevant.
Nope. It's actually quite relevant. The boat is built to be
balanced, under sail or power, with the motor and a typical crew in
the cockpit.
By "balance" I meant that the hull, motor, ballast, and sails work
togther to
cause the boat to to sail and motor as efficiently as possible under a
variety
of applications. In general, it sails and powers well, it doesn't
"pitch" excessively,
and it is fun to sail.
Nice backpedal. It clearly isn't what you meant the first few times
around, but if you think it saves some face for you, so be it.
Jeff, I have not wanted to get into the issue of weight distribution in
detail, since you pretty well had your assed kicked all over the ng on
that one. - Don't forget that you initially claimed that the ballast
extends the full length of the boat, and that was a bad distribution of
mass (and would tend to increase pitching movement). After carefully
explaining to you what the Mac drawings were showing, and responding to
numerous notes, you were finally forced to back off your original
claims, and admit that, well, there wasn't a lot of ballast in the aft
portions of the boat. You then claimed that the ballast extended all
the way to the bow, so that was a problem also. - I then patiently
explained that the ballast tank was pointed toward the bow and tapered
BOTH VERTICALLY AND HORIZONTALLY as it approached the bow (as shown in
the side sectional view and the cross-sections in the drawings you
posted). Not making much headway on either of these points, you then
started to become hyper and jump up and down about the fact that the
ballast tank was near the forward end of the bow, and the motor was at
the stern. - I then explained that the center of mass of the ballast
tank (tapered forwardly and rearwardly) was actually just slightly
forward of amidships, and the motor, while positioned at the stern,
actually comprises only a relatively small portion of the weight near
the stern. - The greatest weight factor being the skipper and crew
and/or guests in the cockpit. Thus, although the motor is in the aft end
of the boat, the crew/guests/skipper comprise a much greater mass factor
at the aft end of the boat.
Jeff, I've gone over this with you and patiently explained it to you a
number of times, yet you refuse to acknowledge that you just didn't get
it. I'm concluding that you thought you had a good "gotcha" to throw at
me, but it turned out you didn't, and you just can't admit it to
yourself or the ng.
or you just showing what type of lawyer you really are. Obviously
the boat was designed to float on its lines with full ballast and
an engine. The issue is whether a different distribution of mass
would lead to a boat that sails better.
Yet you HAVE NO SUGGESTIONS WHATSOEVER as to how to improve the
distribution of mass. - If a bad distribution of mass is a key problem
(actually, it isn't, since the boat sails and motors steadily and
exhibits no excessive pitching movement) then, at a minimum, you should
be able to tell us where you would move the outboard and/or the ballast.
- But you don't want to get into that one, do you Jeff?
And just how would you redistribute the mass, Jeff? - Where would you
move the outboard, and where would you move the ballast?
I would not have designed this boat at all, so don't asked me have I
might change it. All I wanted to do when I started this topic of
discussion was to rationally consider how the different weight
distribution affects stability and balance. But you wanted to turn this
into something quite different.
Nope. I responded to each of your points about weight distribution (see
the above note), and then went on to further, related issues. The bottom
line is that, if your theories were correct, the boat would pitch
uncontrollably and bounce around in heavy weather. - But it doesn't.
The 26M is the result of years of development, feedback, and mods. It
does a lot of things most sailboats can't do. If serves the needs of
most sailors, under the conditions experienced 90% of the time.
That's nonsense!!!
Really? And you have sailed the 26m how many times??????
It's relatively inexpensive,
debatable
if you are willing to compare the costs of new boats to new boats, or
used boats to used boats, and not compare the costs of 15 year old
boats with that of a new Mac 26M similarly equipped.
So why do they seem to depreciate twice as fast as other boats?
Where are your stats on that one, Jeff????
And, (I almost forgot) it's a lot of fun to sail.
only for those with low standards.
And you have sailed the 26M how many times????
Maybe it would. But it's still a lot of fun to sail as it is. (I'm
repeating myself, but isn't that the point, after all?
Is it? Little children think picking their nose is fun, is that
your standard? You fight every detail tooth and nail,
As one of the few on this ng willing to defend the Macs, I'll continue
to do my part to ensure that Mac discussions have at least a semblance
of balance and accuracy. If I'm right, I'll try provide a good, but
balanced and fair defense of the Mac.
even when you
know you're wrong, and then you say "it doesn't matter that I'm lying
because I'm having fun."
You may disagree with my conclusions, Jeff, but tell me where I have
lied to you or anyone else? (Paying attention to what I actually said
in several notes, for a change, and ignoring for a moment WHAT YOU
INTERPRETED as the meaning of portions of some of my comments.) Jeff,
which are the top ten most egregious lies I have posted on the ng? Or,
failing that, the top five? --- Two, maybe?
Jeff, we may have differing opinions, and you seem to have confused
your own opinions as facts, but would you please name the more
egregious instances of my lying? Perhaps you could list the top ten
instances?
Being a clever lawyer, you word things so that they will be taken one
way, but you can claim you said something different. Your comment above
about balance was one such example.
See comments above. The bottom line is that you simply misunderstood
the Mac drawings.
The "double liner" discussion is
another.
See prior comments. - I NEVER said that the ballast tank protected the
entire boat. - That was another of your own, rather convenient "gotcha"
interpretations.
Your claim that the outboard is much lighter than a diesel is
another.
I'm claiming that the outboard is lighter than a diesel with sufficient
power for the Mac when all the associated components, including the
drive shaft and supporting structures are included. Also, I seriously
doubt that a small (e.g., 10-15 hp motor would be sufficient to drive
the Mac through heavy chop and adverse winds.
Your claim that the ballast is very close to the center is yet
another.
It is. - Your problem is that you didn't understand the drawings.
They question is, Jim, when have you been completely truthful?
Although I don't claim omniscience, I have certainly endeavored to be
truthful and to present a balanced response and evaluation of the Mac.
For example, I have noted a number of limitations inherent with the
boat. - I have acknowledged that it normally doesn't sail as fast or
point as high as most conventional boats with weighted keels. I have
acknowledged that it isn't suitable for extended blue water crossings,
etc. I have acknowledged that it is lightly built. - - - Why haven't you
complemented me for being upfront concerning THESE issues, Jeff?
The boat is fast enough to be fun to sail, Jeff. It's not as fast as
some other boats, but it's still fun to sail. - Isn't that the
important factor.? (Actually, I wasn't having too much problem keeping
up with some, though not all, of the larger boats on my last cruise.)
All boats are fun to sail. That's not the point.
It is to me.
You make lots of
claims, and then try to write them off by saying, "but its fun to
sail." What's your point?
Because that's the key factor, from my perspective.
However, I don't think I agree that a typical diesel, with
generator, fuel pump, filters, prop shaft, etc., would weigh about
the same as a modern outboard. - Any stats on that one?
I thought I just gave one. The weight of a 15 Hp Yanmar, including
everything (alternator, pumps, filter) except the shaft and prop is
249 lbs. Clearly one might add another fuel filter or water
filter, and the muffler weighs a few pounds (mine are plastic) but
all of this is only a few pounds, and then your outboard also has a
few extra bits and pieces not included in its base weight. Also,
since the diesel generates almost twice the power from a pound of
fuel, one can claim a huge weight advantage on that front.
You're omitting some items, such as the drive shaft, shaft bushing
assembly, supporting framework in the boat, etc. You're also comparing a
15 hp motor with a 50 hp motor, and you're not addressing the fact that
the Mac requires lots of power to keep in on course in heavy weather,
chop, winds, etc.
That's more than my 50 hp weighs. Also, add the weight of the drive
shaft, the drive shaft bushings, the mounting hardware, the
reinforcements to the hull supporting the motor, etc.
Yes, we know that the mac has no reinforcements to the hull
supporting its motor. You really are intent on showing how lawyers
lie, aren't you?
It has enough.
You made the claim that a diesel is much heavier than an outboard,
and that simply isn't true. Further, the issue has nothing to do
with the possible difference of 20 pounds, it has to do with the
distribution.
Re weight distribution, see my comments above. - I can understand why
you would be embarrassed about that one and prefer that we not discuss
it again.
As to the relative weight, it seems that you want us to accept your
personal opinions about how much the typical diesel engine for a small
sailboat weighs from your
I was quoting from the Yanmar specs, using the most frequently spec'd
diesel for small sailboats. Originally I mentioned to two cylinder
version, because you had asked what someone had in their boat. But for
one as light as the Mac, a one cylinder could do.
Having powered the Mac 26M in somewhat heavy weather, I don't think a
small engine will do the job Jeff. It's a large, light weight boat with
high freeboard and no weighted keel, and it needs lots of power to keep
it one course. Of course, most Mac skippers appreciate the fact that a
50+ hp motor provides a lot of conveniences and enhances the versatility
of the boat. (Incidentally, most Mac buyers seem initially to think that
they don't want a larger engine, but they eventually come to appreciate
the advantages available with the larger engine.)
single example, which omitted the necessary weight of the drive shaft,
the mounting, etc..
I mentioned to driver shaft. However, the weight on that could vary a
lot, and its so low it could be considered ballast.
From your note, it seems that you are saying that I should just shut
up and accept your propaganda based on that (one) example. - Perhaps it
would clarify things if you provided some stats about the weight of
several typical diesel installations on smaller boats. (Including ALL
associated components, including drive shaft, cooling system,
through-hull components, fuel and water filters, pumps, mounting
structures, controls, fuel tanks, etc.)
More lies! I mentioned that the weight for a diesel doesn't include
several items, including the drive shaft. It does include most of the
others you've mentioned - fuel filter, cooling system, pumps,
alternators etc. Some of what you claim are needed for your
installation. Are you trying to claim there is no mounting hardware or
reinforcement, no controls, no fuel tanks? How about the fact that the
gas engine needs twice the fuel?
First, although the transom is sufficiently strong to support the motor,
I don't see any additional support structures for the motor. The
"mounting hardware" consists of some bolts, washers, and the like.
Secondly, there are controls, consisting largely of a tubular connecting
bar and cables extending to the steering mechanism. - Again, nothing
that would add any substantial mass, unless you consider the small
steering wheel to be "massive." The fuel tank is a 10-gal. plastic tank.
- Again, only a few pounds of "mass." Next, regarding the cost of all
that fuel, we get around 3 - 5 miles per gallon at plaining speeds, and
I have probably spent about $25 on gas during the past six months. Of
course, as an attorney, I have lots of money to spend on all that gas,
so it really isn't a major factor. (That's a joke, Jeff. Of course.)
Actually, I spend most of the time sailing, not motoring. Also, because
of work assignments last Summer and Fall I was limited in how much I was
able to take the boat out. Still, gas costs haven't been a major factor.
And of course, the primary issue here is that the weight of the diesel
is well forward, while the outboard is as far aft as possible.
And BTW, the diesel appropriate for a boat as light as yours would be
a single cylinder, which would weigh just about the same as your
outboard.
Care to provide specs on a few examples, Jeff, along with their gross
weight?
The Yanmar 1GM is 179 pounds with transmission.
And, as mentioned above, remember that the Mac, with its high
freeboard and light weight, needs substantial power to get through
chop and adverse wind conditions, to stay on course in extreme
weather, and to dock efficiently. - A small diesel isn't going to cut
it. Also, a
small diesel isn't going to get the boat on a plane either. - No more
quick runs back to the marina, no quick passages to desired skiing
areas, no water tubing for the kids, etc.)
Hey, you're the one who brought this up. You claimed your engine was
much lighter than the diesel on most similarly sized sailboats. I
pointed out you're wrong.
Jeff, in reviewing my note and your responses, I now think I was wrong
in saying the weight of my 50 hp outboard was "much lighter" than a
typical diesel on most sailboats in the 27 - 29 ft range. I think it is
somewhat lighter when all factors are considered, and it's more
powerful, but my statement as written was apparently incorrect. - I had
come to a (mistaken) judgment from working with larger diesels on larger
boats.
Still, my statement about the safety factors entailed in having a fairly
powerful motor on the Mac is accurate, IMO. - For example, when I had
the boat out last, as mentioned earlier, we had a rather substantial
incoming tide and headwind, the waves were breaking against us all the
way out to the sailing area, and there was a lot of traffic, with wakes.
The Mac is lightweight and has a fairly large sideboard area. - If I had
had a 10 - 15 hp motor as is often the case for boats of this size, I
don't think I could have kept it on track within the channel all the way
out. Also, I would not have been able to keep up with the other traffic
going out, which causes further problems. The reserve power is also a
safety factor in the event of inclement weather, tides, etc., out in the
Bay or beyond. Obviously, a 40 - 50 hp diesel would weigh substantially
more. And I also agree that your boat is more efficient using the
smaller diesel, and that the positioning of the diesel is better for
achieving a low cog. - It does take up more interior space than my outboard.
Once again, Jeff, as to the weights of the 50 hp outboard and your 15 hp
diesel, you're right, and I was wrong. My purpose in these Mac
discussions is not to distort the facts or win arguments, but rather to
do my part from time to time in contributing to a more balanced discussion.
Jim
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