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  #1  
Old 12-28-2011, 12:53 PM
patrscoe patrscoe is offline
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Sailboat mast advice

I purchased a 84' S2 11.0A sailboat this past Fall and while reviewing the log, I notice the original owner removed 30" of the mast, apparently from the top as all the rigging looks like the original factory location. The reason sounds like a bridge clearance problem and had to reduce the mast to get safely under it.

I am going back and forth on what I should do with this. I don't want to spend $6k on a new mast and rigging, plus another $4k or so on sails - although I am planning to purchase a new mainsail this winter.

Original Specifications:
36' sailboat, 11.9' beam, 15000 lbs displ
Rig Dimensions: I 46', J 15', P 40' and E 14'
Forestay 345 SF and Mainsail 280 SF
49' bridge clearance

My current P is 37'-6"

http://sailboatdata.com/viewrecord.asp?class_id=1970

I have contacted the original Spar manufacturer for perhaps a identical mast extrusion for installing a sleeve and mast extension but stock this profile anymore and if they have to order this, it will be very expensive.

I have a few thoughts:
1. Leave the mast alone, replace the mainsail with a full batten (as stated, I was going to purchase a new mainsail this winter as the current one has been recut too many times). I am not really happy with this since I am a little OCD about things.

2. Provide a 12" or 18" (not the full 30") mast extension by having a metal shop to fabricate a thicker/stronger custom alum extension. The mast will slide into a sleeve connect to the custom alum extension, rivet the two together. Profile of the fabricated extension would be very similar in shape but I am sure it will not be exactly. I would relocate the lower shrouds and spreaders, and replace the backstay, forestay and upper shrouds. Relocate the boom gooseneck. My new mainsail would match the new dimensions. Genoa furling remain as is besides extending the shaft / replacing the inner forestay.

3. Identical to #2 but provide a custom alum fabricated extension from the foot to just below the cabin ceiling, cut the existing mast to match original length and I will end up replacing the furling (genoa).
Approximate budget would be close to $6k. Not sure if this is worth going to this extensive work.

4. Identical to #1 but also installing a Solent Stay system. This would add more sail area as these sailboats can be a little sluggish in light air due to the beam and displacement.

Any thoughts or advice, or any other options that I have not thought of?

Patrick
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  #2  
Old 12-28-2011, 01:22 PM
michael pierzga michael pierzga is offline
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Id leave the mast alone and concentrate on fitting the biggest mainsail possible. Big roach. Perhaps modifing the masthead crane to accomadate the roach.

With the headsail...perhaps lower the headstay a few inches and use a slightly shorter luff length jib, then fit a masthead CODE type asymetric, jumbo , roller headsail for reaching. These sails are very powerful in the 60 to 110 awa range
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  #3  
Old 12-28-2011, 01:38 PM
patrscoe patrscoe is offline
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By replacing the mast head crane to accomendate a increased roach, could the crane be extended a few inches or so to gain more mast height? I never seen anyone do this before.
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  #4  
Old 12-28-2011, 02:05 PM
michael pierzga michael pierzga is offline
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The masthead crane modification wont gain extra hoist it will allow a bigger mainsail head and leeach.
Id have to look at your rig geometry to see if you could modify the crane. Inline rigging or aft swept spreaders ?

For you its best to contact your local mast builder...propose a masthead crane modification to hang a bigger roach..leach...mainsail and listen to his observation. The masthead crane is your backstay and headstay attachment so this modification must be well concieved.

Lengthning your mast plus new sails and standing rigging is a big hole in your bank account.

Id keep her stubby then work on other ways to bring up performance. Adding big sails, polishing the bottom, Fairing the keel or reskinning a rudder are cheap.

The masthead pictured is to accomadate a full roach mainsail
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  #5  
Old 12-28-2011, 04:01 PM
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Perm Stress Perm Stress is offline
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Quote:
Originally Posted by patrscoe View Post
I purchased a 84' S2 11.0A sailboat this past Fall and while reviewing the log, I notice the original owner removed 30" of the mast, apparently from the top as all the rigging looks like the original factory location. The reason sounds like a bridge clearance problem and had to reduce the mast to get safely under it.

I am going back and forth on what I should do with this. I don't want to spend $6k on a new mast and rigging, plus another $4k or so on sails - although I am planning to purchase a new mainsail this winter.

Original Specifications:
36' sailboat, 11.9' beam, 15000 lbs displ
Rig Dimensions: I 46', J 15', P 40' and E 14'
Forestay 345 SF and Mainsail 280 SF
49' bridge clearance

My current P is 37'-6"

http://sailboatdata.com/viewrecord.asp?class_id=1970

I have contacted the original Spar manufacturer for perhaps a identical mast extrusion for installing a sleeve and mast extension but stock this profile anymore and if they have to order this, it will be very expensive.

I have a few thoughts:
1. Leave the mast alone, replace the mainsail with a full batten (as stated, I was going to purchase a new mainsail this winter as the current one has been recut too many times). I am not really happy with this since I am a little OCD about things.

2. Provide a 12" or 18" (not the full 30") mast extension by having a metal shop to fabricate a thicker/stronger custom alum extension. The mast will slide into a sleeve connect to the custom alum extension, rivet the two together. Profile of the fabricated extension would be very similar in shape but I am sure it will not be exactly. I would relocate the lower shrouds and spreaders, and replace the backstay, forestay and upper shrouds. Relocate the boom gooseneck. My new mainsail would match the new dimensions. Genoa furling remain as is besides extending the shaft / replacing the inner forestay.

3. Identical to #2 but provide a custom alum fabricated extension from the foot to just below the cabin ceiling, cut the existing mast to match original length and I will end up replacing the furling (genoa).
Approximate budget would be close to $6k. Not sure if this is worth going to this extensive work.

4. Identical to #1 but also installing a Solent Stay system. This would add more sail area as these sailboats can be a little sluggish in light air due to the beam and displacement.

Any thoughts or advice, or any other options that I have not thought of?

Patrick
In many senses it would be good to go back to original as close as possible.

I know firsthand about mast lengthening for 54ft yacht done the following way:
sleeve and extension piece for lengthening from below;
New rigging designed to keep it all in column (it was a secondhand mast from different boat).

In your situation, new section added to bottom of mast, and relocating all the rigging and boom attachment points would do perfectly well structurally.
(it is also possible, that mast was shortened from below, with all the fittings but the boom at original positions; than all you will do would be fit lengthening to the bottom of mast and order new rigging of increased lengths)
Being at the bottom, exact fit is not that important -if it is structurally continuous, and corrosion resistant, do not make the galvanic pair with main material of mast, nothing more is required.

The somewhat nasty problem would be the gate for mainsail entrance in the groove.
You will need to close it in such a way as to ensure smooth passage of sliders and batten cars up and down. Nothing really big, just embarrassing to iron out all the bugs and small tolerances of closing pieces.
One of the ways around this -external mainsail track.
Less headache, but more money spent and some extra weight up the mast.
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  #6  
Old 12-28-2011, 04:35 PM
patrscoe patrscoe is offline
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I'm about 90% sure they cut the top. One sign is that the goose neck is welded to the mast and I don't see any areas on the mast of this relocation.
The sail track will need to replaced.

The common sense thing would be to live with it, buy a new main and a feathering prop.
I need to look at all my options. That's why I was considering to provide a simple 12" or so, bottoming extension and size the new main accordingly. Some of the rigging will need to be modified but maybe that's a good thing , replacing old standing rigging and turn buckles.
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  #7  
Old 12-29-2011, 01:18 AM
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PAR PAR is offline
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Have you checked with Dwyer Mast? They've purchased many of the former production boat extrusion dies and may very well have the piece you need.
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Old 12-29-2011, 04:09 AM
powerabout powerabout is offline
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Quote:
Originally Posted by michael pierzga View Post

The masthead pictured is to accomadate a full roach mainsail
LOL Good one ( tp52?)
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  #9  
Old 12-29-2011, 05:32 AM
michael pierzga michael pierzga is offline
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Quote:
Originally Posted by patrscoe View Post
I'm about 90% sure they cut the top. One sign is that the goose neck is welded to the mast and I don't see any areas on the mast of this relocation.
The sail track will need to replaced.

The common sense thing would be to live with it, buy a new main and a feathering prop.
I need to look at all my options. That's why I was considering to provide a simple 12" or so, bottoming extension and size the new main accordingly. Some of the rigging will need to be modified but maybe that's a good thing , replacing old standing rigging and turn buckles.
Consentrate on all the small things.
Work on the bottom of the boat.

Make sure that the boat floats on its designed lines and righting moment. As boats age ,weight distribution is an issue, they either drag their ass or plow their bow.
Also concerning Big Mainsails. Im presently sailing with a big head main and full battens. The main leach is so big that we cant tack with full main hoist...the backstay interferes with the leach. We typically sail upwind with one reef in the keep the main leech off the backstay. Its a hassle but when on a reach, full main, the boat is turbo charger. A cheap turbo, Well worth the hassle.
Go for as many cheap performance boosts as possible
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  #10  
Old 12-29-2011, 07:41 AM
patrscoe patrscoe is offline
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Yes, I checked with Dwyer, JSI, Rig-Rite, etc...

Schaefer Marine fabricated the masts in 1975 - 1978, Hall Spars started in 1980 but stopped in 1982 and only fabricated the boom from their after. Offshore and another fabricator took over. The 11.0 mast was a performance mast extrusion not a cruising mast. Hall has a similar profiles instock but not exact. That means they need to purchase 5,000 to 10,000 lbs min for additional stock from their extrusion fabricator (which is not cost prohibitive). What I have been told is that whatever spar manufacturer that has the die, then they have the patent on it and no one else has the "exact" profile, similar but not exact.
At least that is what I have learned but talking to about 6 spar companies and 3 rigging companies.

*** Would installing a rigid boom vang eliminate the tacking problem with a slightly larger roach on your mainsail?

*** Any thoughts on a Solent Stay?

*** If I don't proceed the mast extension, anything else that might help?
- Adding feathering prop
- New mainsail with increased roach with perhaps converting my boom vang to a rigid to eliminate my topping lift
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  #11  
Old 12-29-2011, 07:52 AM
patrscoe patrscoe is offline
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Michael,
You stated "With the headsail...perhaps lower the headstay a few inches and use a slightly shorter luff length jib, then fit a masthead CODE type asymetric, jumbo , roller headsail for reaching. These sails are very powerful in the 60 to 110 awa range"

What is a masthead CODE? Is it a larger masthead with a headstay arm that extends out more? Sorry, not sure what your intent is here?
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  #12  
Old 12-29-2011, 04:07 PM
Chuck Losness Chuck Losness is offline
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It is not uncommon for owners to order a boat with a shorter mast. Especially in areas known to have higher wind speeds. 2 feet shorter was the typical amount to shorten a mast. On the west coast this was very common in San Francisco. PHRF even has handicaps for boats with short rigs. My recollection is that the rating adjustment for a short rig was 6 seconds per mile but no more than 12 seconds per mile. What that means is if you raced your boat against a stock boat over a 10 mile course the stock boat would get to the finish 1 to 2 minutes before you would. That's one or 2 minutes in probably 2 hours of sailing. We are talking about trivial increases in speed. In heavy air there would probably be no difference in boat speed. How many thousands of dollars do you want to spend to go at best marginally faster than what you have now? If you are not going to race, then you will most likely turn on the engine in light airs and you would not receive any benefit from increasing the length of you mast.
Before you do anything you need to go sail your boat and get to know its handling characteristics. Does it have lee helm? Or weather helm? How does it sail in light air, medium air and heavy air? What is the typical wind in your area? Are you going to race the boat? And the questions goes on and on. You will need all this information and more before you can even start to think about making changes to your mast. Without this information you will just be shooting in the dark as to whether the perceived benefit would be worth the cost.
You will find "experts" who will only be too happy to take your money while they experiment with your boat. Be careful and good luck
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