!!
JimC wrote:
Jeff wrote:
JimC wrote:
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. -
How so? Only a total idiot could claim that a 250 pound engine
hanging on the stern plus 300+ pounds of water up in the bow could
have negligible affect on the pitch moment of a boat that only weighs
3600 pounds! Do you really think there's a single reader here that
believes you???
Don't forget that you initially claimed that the ballast
extends the full length of the boat,
And it does. If you claim otherwise, you're a boldface liar. The
most that you can claim is that the tank is rather small aft (its
still much bigger than simply a drainage tube) but all this mean is
that there's more weight up forward. You loose either way.
and that was a bad distribution of
mass (and would tend to increase pitching movement).
So are you claiming that all naval architects are wrong when they try
to minimize weight in the extremities? You can certainly claim the
pitching isn't too bad (though few here would believe you) but you
certainly can't claim that the mass distribution has no affect.
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.
As I said only a liar would claim the tank doesn't extend the entire
distance. I only admitted there wasn't much water ballast aft.
You then claimed that the ballast extended all
the way to the bow, so that was a problem also. - I then patiently
though incorrectly
explained that the ballast tank was pointed toward the bow and tapered
BOTH VERTICALLY AND HORIZONTALLY as it approached the bow
The tapering is clearly only in the last few inches. With the
majority of the water ballast well forward of the mast, this is the
equivalent of having a hundred gallon water tank under the vee of a
slightly larger boat. Not a good thing.
(as shown in
the side sectional view and the cross-sections in the drawings you
posted).
I POSTED???? Those are on the MacGregor site!!! I posted no drawing,
I merely posted a link to the factory site! My God, you really are a
boldface liar!
Not making much headway on either of these points,
Find one reader of this that believes you.
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. -
As clearly shown in the factory diagram.
I then explained that the center of mass of the ballast
tank (tapered forwardly and rearwardly) was actually just slightly
forward of amidships,
Are you saying the diagram from the factory lies??? It clearly shows
the largest cross-section to be halfway between the mast and the bow.
and the motor, while positioned at the stern,
actually comprises only a relatively small portion of the weight near
the stern.
Nonsense. Even a 5th grader can do the math that shows that the
contribution to the moment of inertia of the engine is roughly equal
to that of the crew.
- The greatest weight factor being the skipper and crew
But the moment is proportional to the distance SQUARED from the center
of mass. So the moment of the engine will clearly be larger than that
of the skipper and one or two crew, and possibly be equal to a full
crew. Its math Jim, hard to argue with.
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.
Its the moment, not the mass.
Jeff, I've gone over this with you and patiently
though stupidly, because you seem to ignore the moment, and focus on
the fact that the large mass hanging off the stern is balanced by the
large mass towards the bow.
explained it to you a
number of times, yet you refuse to acknowledge that you just didn't get
it.
Get what? That you can't do simple sums? That you can read a simple
drawing?
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.
Sure thing. SHow me someone that believes you on that, Jim.
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?
I don't see your point. If you stay with a variety of the design
parameters, such as light weigh on the trailer, a large engine, etc,
it becomes hard to distribute the weight otherwise. It may even be
that this is a reasonable solution, perhaps even the best, given the
constraints.
But for most sailers, the constraints that led to this design are not
important, and the required compromises are not desirable. You're
asking me to make one change that would reduce the pitch moment, and
the answer is that's hard given that you want a 250 pound engine
hanging off the stern.
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),
No - you denied the obvious truths.
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.
Why would you say that? Oh, I forgot, you're a lawyer.
I never made any claim that it "pitches uncontrollably" but since you
bring it up, maybe it does.
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??????
What is the significance of that?
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????
Just look at the asking prices. We've been through this before.
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.
That's a laugh.
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?
Its hard to find a place where you told the truth. You keep saying
"show me where I lied" but you ignore it when I do.
(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?
I did that in my last post. So that's one lie right there.
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.
Are you denying that the largest cross-section of the ballast tank is
at station one, well forward of the mast? Are you?
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.
By going into detail on the "double liner" you implied such
protection. Especially after you were informed the the term "double
hull" specifically implies such complete protection. You're being
disingenuous here, Jim.
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.
That's not what you claimed originally Jim, and you you know it.
That's another lie! You specifically claimed that the diesel in
similar sized boats was much heavier than the outboard on a Mac. Now
you claiming that because of the poor design of the hull it needs the
huge engine that no other 26 footer requires.
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.
Again - are you claiming that the cross-section of the tank is not
substantially large at station one than at any other? Are you trying
to say blue is red over and over and hoping someone will buy it?
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?
They do seem to be self evident.
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.
Then why don't you just leave it at that? Remember, I've said a
number of times that it a reasonable boat for certainly situations -
I've haven't been claiming its inherently evil. Actually, all I've
done is try try to keep you honest on some of the more outlandish claims.
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,
I certainly didn't ignore the shaft, I mentioned right up there.
Another lie.
supporting framework in the boat,
Are you seriously claiming there is no "supporting framework" on the
Mac. I already pointed that out to you, so that's yet another lie on
your part. How can you really claim you never lie?
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.
Why does the Mac "require" it, when no other 26 foot sailboat does?
Wouldn't that seem like a design flaw?
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.
So are your really claiming that weight distribution has no affect?
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.
That would seem to be a flaw. My boat has no weighted keel and high
freeboard, and a couple of small engines handle it very nicely. In
fact the original design (and most of my sisterships) only have twin
9.9 HP outboards.
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,
Only because its reinforced, you jackass!
I don't see any additional support structures for the motor.
Yah right. Give me a friggin break, Jimbo.
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.)
It isn't the cost, you bozo! Its the range! You say you get 30 miles
from that tank. A small diesel pushing a normal sailboat your size
would be 3-4 time more efficient. If you wanted to go any distance
you'd need a second tank while the diesel wouldn't. That's about 70
pounds of fuel.
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.
again, its range, not cost.
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.
I don't get it. Why does the Mac "need" an engine 3 times as powerful
as all of its competition. And why is that a safety feature?
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