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Old 11-09-2015, 09:08   #16
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Re: Why is my mast so thick on my "lightly built" boat?

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Originally Posted by VinnyVincent View Post
Why would they make the mast so thick on a lightly constructed coastal/lake boat? Lower quality aluminum? Thinner gauge? It's not any taller, so that can't be it...
So it doesn't break! Last weekend on the IJsselmeer in The Netherlands, there was a race planned that got cancelled due to high winds. 30kts?

Even then several boats lost their rigs. This is what happens when you don't change your stays for 20 years or check your fittings or don't keep your stays tight enough.

Better to fix things BEFORE they break. I think they call that "preventive maintenance"?
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Old 11-09-2015, 09:14   #17
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Re: Why is my mast so thick on my "lightly built" boat?

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So it doesn't break! Last weekend on the IJsselmeer in The Netherlands, there was a race planned that got cancelled due to high winds. 30kts?

Even then several boats lost their rigs. This is what happens when you don't change your stays for 20 years or check your fittings or don't keep your stays tight enough.

Better to fix things BEFORE they break. I think they call that "preventive maintenance"?

Well I just got all new chain plates and rigging put on that old clunker I have(probably the most money anyone's spent on it in the last 20 years), so combine that with the huge mast and it's a "blue water" boat that's suitable for a couple circumnav's before the next refit, right?...right?
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Old 11-09-2015, 09:16   #18
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Re: Why is my mast so thick on my "lightly built" boat?

I hope your mast goes down to the keel and is "pinned" to a mast step that is in good condition.
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Old 11-09-2015, 09:29   #19
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Re: Why is my mast so thick on my "lightly built" boat?

Forty years ago I had a new 20' trailer yacht which had a 4" diameter mast. I did the calculation of the weight of the mast X 1/2 the mast heigh and the answer was in foot pounds. That boat had a cast iron hinging center board from memory weighing 300 pounds. I changed my rig to a 3" diameter much lighter mast with wider spreaders for its 3/4 rig and added lower shrouds all properly designed.

Doing that resulted in an improved righting moment which was comparable to adding another 100 pounds the ballast in the lifting keel but without adding any weight. Looking at it another way; the original rig was comparable to theoretically sailing around with a car battery hanging half way up the new mast. That was the righting moment difference.


That little yacht sailed so much better and was safer with the new lighter mast. It was like a new yacht. Because masts are comparatively long and keels comparatively short; the weight of the mast needs several times its weight of ballast to oppose it.


Imagine a seesaw with one side 15' long. That is your mast (center of gravity) half height. The other side of the seesaw is only 3' long. That is your keel half length. If a person weighing 100 pounds sits on the long end it would need a 500 pound person on the short end to balance the seesaw.


In the case of my boat (40 years ago) it originally had a big heavy mast and simple basic rigging to bring the purchase price down at the expense of its sailing ability.


A lighter mast though needs good, properly designed more expensive rigging to support it.
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Old 11-09-2015, 09:54   #20
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Re: Why is my mast so thick on my "lightly built" boat?

Just a simple question. Did they design with fewer of lighter stays?
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Old 11-09-2015, 10:05   #21
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Re: Why is my mast so thick on my "lightly built" boat?

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Originally Posted by a64pilot View Post
Often times in manufacturing pieces parts are picked based on cost and availability, not necessarily with being the best part, you'll drive yourself nuts sometimes trying to figure out what the designers were thinking, then you realize accounting dept picked X part, not a designer.
Yep, there are certain common size mast extrusions. If the calcs come out in between two extrusions, Some people will opt for the next size up, some will opt for the next size down.
Then there are owners who want to rethink everything when they buy a new boat. maybe some guy insisted on a bigger extrusion.
Then as mentioned, there is availability. If the perfect extrusion was out of stock and the maker wanted to get the boat shipped, they might have opted for what was available.
It seems modern boats have smaller extrusions and more spreaders. etc. but not sure about that.
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Old 11-09-2015, 10:17   #22
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Re: Why is my mast so thick on my "lightly built" boat?

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Just a simple question. Did they design with fewer of lighter stays?
Looks like a pretty standard single spreader sloop rig to me. It's simular to any other production boat that size I have seen.
Has six shrouds, 3/16" lowers and 7/32" uppers, with a 7/32" forestay and backstay(split at the bottom into two 5/32").
Mast is just over 32' I think.
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Old 11-09-2015, 10:56   #23
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Re: Why is my mast so thick on my "lightly built" boat?

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What is the wall thickness compared to the others? Given the same materials, a larger outside diameter with thinner wall thickness *could* be stiffer/stronger with less weight.
Yep what he said. larger diameter thiner wall could be stiffer stronger and lighter if done properly
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Old 11-09-2015, 11:41   #24
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Re: Why is my mast so thick on my "lightly built" boat?

is a decent gom boat.. cruise to fort jefferson and all over. ye wont die too much. is good experience. a newport was originally built in newport, costa mesa, cali. another factory was made back east, and these boats were day sailors in pacific ocean, with its long rolling swells, and occasional decent breeze.
i wouldnt go out in a storm in it. although i did sail the gom in a seidelmann 37 which is a lil flimsier feeling than the newport 30 was, even at a dock.
just reef early. might live..we did.
the thirty i sailed which was owned by a friend, was not too tender for its size, same with next door neighbors on mooring in san diego, off coronado's tidelands park. yes i was there a few years. actually worked for a living. we didnt sail in anything weathery-er than slight hazy mebbe fog, so i cannot tell ye how it felt in pacific...we stayed inside sd bay.
btw, the original masts on the costa mesa builds were le fiell masts. local built.
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Old 11-09-2015, 11:42   #25
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Re: Why is my mast so thick on my "lightly built" boat?

Someone asked earlier if that is the mast original to the boat. That's a good question. There are many folks who replace masts with whatever they can find in a boat yard.

Any other Newport 28s around there?
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Old 11-09-2015, 13:33   #26
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Re: Why is my mast so thick on my "lightly built" boat?

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is a decent gom boat.. cruise to fort jefferson and all over. ye wont die too much. is good experience. a newport was originally built in newport, costa mesa, cali. another factory was made back east, and these boats were day sailors in pacific ocean, with its long rolling swells, and occasional decent breeze.
i wouldnt go out in a storm in it. although i did sail the gom in a seidelmann 37 which is a lil flimsier feeling than the newport 30 was, even at a dock.
just reef early. might live..we did.
the thirty i sailed which was owned by a friend, was not too tender for its size, same with next door neighbors on mooring in san diego, off coronado's tidelands park. yes i was there a few years. actually worked for a living. we didnt sail in anything weathery-er than slight hazy mebbe fog, so i cannot tell ye how it felt in pacific...we stayed inside sd bay.
btw, the original masts on the costa mesa builds were le fiell masts. local built.
If i remember right off the newport page I am on, the 30 is quite a bit different than the 28. Different designers and everything. From what I understand, the 28 is pretty much a scaled down 41. Both designed by C&C. I think I read that Gary Mull designed the 30 and it's more of a cruising oriented design when compared to other newport boats. I am also pretty sure that the MK1's weren't even manufactured by capital yachts, but another company.

I was actually trolling you guys when I said it's now bluewater since I got new rigging lol...it's a good boat for my use, though...which is generally just daysailing with an overnight stay here and there. I still haven't tried it in the gulf(that's why I got new rigging)

It does sail really nice and I can even take my hands off the wheel and it will go straight close hauled...it can be a little squirrelly downwind. I'd say the roughest conditions I've had it in would be 2-3' chop out in the bay in about 20kn of wind, which was real close to needing to reef, but it handled it better than expected. Once it gets heeled over good, it starts to stabilize.


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Originally Posted by SkiprJohn View Post
Someone asked earlier if that is the mast original to the boat. That's a good question. There are many folks who replace masts with whatever they can find in a boat yard.

Any other Newport 28s around there?
There's actually one at the ASA 104/106 course I'm about to attend in a few months, so I will be able to check there.
Comparing pics of my boat to others, it really does look like the same mast, but it's hard to tell for sure in a picture.
The boat did come with a very detailed log book and has no mention of the mast ever being replaced.

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Originally Posted by farm sail View Post
Yep what he said. larger diameter thiner wall could be stiffer stronger and lighter if done properly
At this point, that seems most likely. I will have to do some real, scientific research this weekend with the butt end of a screwdriver while holding my ear up to various masts
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Old 11-09-2015, 14:11   #27
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Re: Why is my mast so thick on my "lightly built" boat?

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Just a random question to the OP - Are you sure your mast is original to the boat? Not saying it isn't or anything because I'm not familiar with them. But I was just wondering if it was possible that a previous owner replaced it with something bigger. Someone posted a picture of another Ex26 like mine that has a mast that appears way larger in diameter than all the others, so I can only assume that's what happened. So I was just curious if that had happened to you also. Just curious is all
Darn. Beat me to it !

I'm guessing that this section was the cheapest one in the area at the time the boat was rigged. It was probably shortened and made to fit.
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Old 11-09-2015, 19:23   #28
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Re: Why is my mast so thick on my "lightly built" boat?

Your boat is tender. Long ago stiff meant a vessel that took a large amount of force to heel. If the heeling force ( a lull in a strong wind,for example ) paused for more than a moment, the vessel would whip back to and sometimes through the vertical ,ridding herself of her sticks. These days, stiff describes a vessel that " stands up" to a stiff (there you go) breeze and waves. Not very scientific, I realize but close enough. I was dismasted by a bridge in my 1934 Matthews Sailer by Bill Atkin, and decided to change from the low aspect sail plan to a modern high aspect masthead sloop. I bought a 40 foot aluminum mast from Kenyon and cut five feet off the seventeen foot boom. I added a v-shaped oak bowsprite and boomkin, Two chain plates backed by 2"by 12" square oak backing plates. The batten less negative roach mainsail came out to 202 sq.ft. I could hold my own but not beat J24s in the Indian River. If in the open sea, they didn't stand a chance. SKYLINER was 25'7" on deck, 8'6" beam, hard chined.If she had enough wind and too much sail, she would plane at up to sixteen knots. (she did, twice, once with witnesses ). I have no mechanical or engineering credentials. I'm hopeless at math, but I can visualize things and create them with boats. I just can SEE what will work and,all I can say is, nothing I ever put up ever fell down.
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Old 11-09-2015, 20:09   #29
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Re: Why is my mast so thick on my "lightly built" boat?

I think Cheechako has the best guess. The builder had a choice of two extrusions (there aren't that many sizes of extrusions available) and went with the bigger rather than the smaller. It cost him money but he probably slept better at night.

Why?

Sailboat builders don't have a lot of engineers like Boeing. They do their best but most will build in a little extra safety margin to compensate for a certain degree of uncertainty.

I believe that your rig doesn't have either forward or after lowers? This means that the middle of the mast can bow forward or back and come out of column (which causes it to fail). The bigger mast section would reduce this bending.

At least with masts - bigger isn't always better but it is stiffer

While it's never been confirmed, this is a reasonable guess of what caused the dismasting of the Gunboat 55 Rainmaker last year. It had no after lower stays in the rig. The sudden acceleration of the boat from the wind burst followed by perhaps an equally sudden deceleration as the boat buried its bow in the back of the next wave could have whipped the middle of the mast enough to bring it out of column. Just conjecture.
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Old 11-09-2015, 21:27   #30
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Re: Why is my mast so thick on my "lightly built" boat?

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I think Cheechako has the best guess. The builder had a choice of two extrusions (there aren't that many sizes of extrusions available) and went with the bigger rather than the smaller. It cost him money but he probably slept better at night.

Why?

Sailboat builders don't have a lot of engineers like Boeing. They do their best but most will build in a little extra safety margin to compensate for a certain degree of uncertainty.

I believe that your rig doesn't have either forward or after lowers? This means that the middle of the mast can bow forward or back and come out of column (which causes it to fail). The bigger mast section would reduce this bending.

At least with masts - bigger isn't always better but it is stiffer

While it's never been confirmed, this is a reasonable guess of what caused the dismasting of the Gunboat 55 Rainmaker last year. It had no after lower stays in the rig. The sudden acceleration of the boat from the wind burst followed by perhaps an equally sudden deceleration as the boat buried its bow in the back of the next wave could have whipped the middle of the mast enough to bring it out of column. Just conjecture.
Carl,
The Newport 28's have a lower shroud ~perpendicular to the mast, sharing a chainplate with the upper shroud (IIRC); and also, about 18" ahead on deck, a forward lower shroud; plus the forestay (mine is rigged with a removable Solent(?) too) and split adjustable backstay.
It is a heavy mast section for whatever reason they equipped them, I don't mind, it's probably stronger and might last a little longer. My hull and deck seem pretty tough too.

For Zee, I think the main longest running Capital production shop was in Harbor City, CA (address given in my manual), not too far west of Costa Mesa on the other side of Long Beach (haven't been in that area in 30 years, was mostly in Orange County; not a bad place to visit, but 'living' there?...).
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