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Old 09-08-2013, 01:07   #46
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Re: Installing an Inner Forestay

And the running back stays. I found some heavy duty 4:1 purchase blocks and have two attachment points for different applications. And can store the dyneema at the chain plate when not in use.

Also, have a pair of short T-tracks (second picture) for sheet cars and a new staysail, which I'll get pictures of on a later date, probably during a shakedown sail'n.
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Old 09-08-2013, 13:19   #47
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Re: Installing an Inner Forestay

On running backs, the attachment point to the deck is usually fairly far aft. That makes the angle at the mast fairly slack which greatly reduces the strain on the whole running back system. Not an engineer but the load on stay drops tremendously as the angle at the mast increases from the minimum 12 degrees or so.

The SpinLock rope clutches do not need tension on the tail to release. Assume that others don't either.

Nice job on the metal work. Looks like the factory did it.
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Old 05-09-2017, 16:24   #48
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Re: Installing an Inner Forestay

I know this thread is very old ...

Quote:
Originally Posted by roverhi View Post
Personally, would not go with a bow drogue. If conditions are bad enough that you cannot sail, it is dangerous to have the bow into the wind. The wave action will throw the boat stern first into the wave trough and puts extreme pressure on the rudder. Your spade rudder boat is particularly vulnerable to damaging the rudder in those conditions.
If the spade rudder can rotate through 360 degrees -- e.g., you have a tiller not a wheel, AND the rudder stock is "geometrically normal" which means it is at 90 degrees to the hull surface in all directions, AND there is sufficient clearance to propellor or anything else sticking down from the bottom, THEN and ONLY THEN is it safe to use a bow drogue.

If its NOT a spade rudder, then its certainly not safe. If its a skeg hung rudder, you will rip the skeg off and you will sink. If its keel hung, you'll rip the rudder off.
If you use a wheel instead of a tiller, you'll destroy all that stuff. If the shaft is not "normal" to the bottom, it will bend and/or fail and/or break the rudder tube inside the boat.

Quote:
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As far as the deck fitting for your staysail, a beefy beam laminated in place or a couple of hefty pieces of plywood laminated to the deck that will carry the load out to the hull should do you just fine.
A storm jib has the exact same load as a genoa: the max load is a function of righting moment, not sail area or wind speed or anything else. If this inner forestay is just for a staysl used reaching or downwind, then a simple beam may be sufficient. For a storm sail, it MUST be as strong as your forestay fitting.

I agree with the rest of this post:

Quote:
Originally Posted by roverhi View Post
I wouldn't halve the 'J' measurement for the deck fitting, would put it somewhere around 2/3rds 'J'. You can get a sail that's large enough to give you effective drive when the jib is struck but you still want to sail. It will also be a great sail for reaching conditions in conjunction with the jib. You could put reef points on the sail and use it as a storm sail. If you wanted to put roller furling on it, could furl it down any size that you want though I'm not fond of r/f on staysails. Might want to consult a N/A to figure out where exactly would be the best place on deck to locate it to balance the rig.

Running backs should take care of any pumping that you have with the staysail. Using Dyneema or Spectra line for the runners and the staysail stay. Might even be able to get by using deadeyes rather than blocks or levers to tension the stays or at least the staysail stay. It takes very little tension on the staysail stay to pull the mast out of column.

If you want to be careful with your main. Would reccomend a Storm Trisail. They aren't the best setting sail but some sail aft of the mast is necessary for a boat to go to windward in serious winds. A third reef in the main will give a much better setting sail but you risk damaging the main. That is the real reason for a storm trisail. Last thing you want is a destroyed main with several thousand miles to your next landfall on an Island without a sail maker or repair possibilities.
Let me re-inforce this really good reason to have a trys'l instead of deep main reefs. As Rover mentioned, things break in heavy weather. A trys'l does not use anything related to the main, besides the mast itself. So its as redundant a system as one can practically have.

Another good reason for the trys'l is that it is sheeted to the rail, and sheeted as flat as a board. This means it keeps the bow off the wind, preventing the boat from tacking in the big and CONFUSED seas that are typical in heavy conditions. This aspect is missed by a lot of people. Ensuring the boat maintains directional stability, with the bow 45 degrees or so off the wind, even in confused seaway, is the reason you are fundamentally safer under trys'l than under any other sail configuration.
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Old 05-09-2017, 16:44   #49
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Re: Installing an Inner Forestay

Quote:
Originally Posted by roverhi View Post
On running backs, the attachment point to the deck is usually fairly far aft. That makes the angle at the mast fairly slack which greatly reduces the strain on the whole running back system. Not an engineer but the load on stay drops tremendously as the angle at the mast increases from the minimum 12 degrees or so.
In my experience, I prefer the running backstays to come down to the deck further forward, preferably just forward of the cockpit, and further outboard, to the rail as Delmurray did.

Having the backstays forward means the backstays stay out of the cockpit when they are slack. This is important for crew safety, especially in heavy air which is when they are needed.

Having the backstays outboard, nearer the maximum beam of the boat, and forward means the backstays can often be left tensioned even if you tack. This is again a very important safety feature in heavy air.

Since the whole point of storm sails or smaller sails is to allow sailing to continue to be safe even when the weather deteriorates, making choices to favor safety seems a good idea. The difference in load is not significant, in that the cost difference is quite low using modern materials.
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Old 05-09-2017, 17:01   #50
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Re: Installing an Inner Forestay

Quote:
Originally Posted by u4ea32 View Post
In my experience, I prefer the running backstays to come down to the deck further forward, preferably just forward of the cockpit, and further outboard, to the rail as Delmurray did.

Having the backstays forward means the backstays stay out of the cockpit when they are slack. This is important for crew safety, especially in heavy air which is when they are needed.

Having the backstays outboard, nearer the maximum beam of the boat, and forward means the backstays can often be left tensioned even if you tack. This is again a very important safety feature in heavy air.

Since the whole point of storm sails or smaller sails is to allow sailing to continue to be safe even when the weather deteriorates, making choices to favor safety seems a good idea. The difference in load is not significant, in that the cost difference is quite low using modern materials.
If safety of the boat is important, having runners forward as you suggest means that the boom interferes with them (or vice versa). Thus, if you have an accidental gybe with the windward runner set, you risk loosing the boom or the whole rig. With the runners aft far enough to clear the boom, and one or more reefs in the main, one can leave both runners set, giving best support to the mast and keeping the runners from whacking a crew member.

This setup has worked well for us for many miles and years at sea.

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Old 05-09-2017, 19:50   #51
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Re: Installing an Inner Forestay

Jim, I always enjoy and learn from your experience that you share on this site. Thank you!

I agree that if one reefs the main or sets a trys'l that is below the runners, then leading the running backstays behind the boom makes a lot of sense. On your boat, which looks like a 7/8 or so rig, this probably works very well on your boat.

On most masthead boats, and especially masthead cruising boats, runners are not needed downwind when gybing can happen, so the location of the runners is a moot point in these cases.

In this discussion, we have been talking about runners supporting an inner forestay, hence upwind or reaching conditions, where the boom won't reach runners that are forward and outboard.

In storm conditions, where the confused seas can lead to anything happening at any time, including gybes, the main or trys'l is sheeted in so it won't hit runners led forward and outboard. By having them forward and outboard, they can remain set. This is quite safe.

If in storm conditions and running with main or trys'l, the approach you mentioned -- reefing the head of the mains'l or trys'l under the runners and leading them aft of the boom -- works.

But of course, if you are heading downwind in storm conditions, you'd probably not have either hoisted, just go downwind with stays'l or storm jib to avoid the round up and make gybing a non-event. So having the runners forward and outboard is again OK.

An uncontrolled gybe is a problem no matter where the runners are led. With running backstays led aft of the boom, a crash gybe results in the main held more-or-less centerline, which can pin the boat. Like this:

https://youtu.be/OC2_uZ7Ys00
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Old 05-09-2017, 20:05   #52
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Installing an Inner Forestay

Quote:
Originally Posted by u4ea32 View Post
I know this thread is very old ...

If the spade rudder can rotate through 360 degrees -- e.g., you have a tiller not a wheel, AND the rudder stock is "geometrically normal" which means it is at 90 degrees to the hull surface in all directions, AND there is sufficient clearance to propellor or anything else sticking down from the bottom, THEN and ONLY THEN is it safe to use a bow drogue.

If its NOT a spade rudder, then its certainly not safe. If its a skeg hung rudder, you will rip the skeg off and you will sink. If its keel hung, you'll rip the rudder off.

If you use a wheel instead of a tiller, you'll destroy all that stuff. If the shaft is not "normal" to the bottom, it will bend and/or fail and/or break the rudder tube inside the boat.

. . .
It seems to me that other people's experience indicates otherwise.

The Pardey's talk about using a drag device off their bow. That was sprung back so the the boat lay 40* or so off the wind. Their boat was a full keel.

Apparently they did this on a number of boats that they were delivering too so it worked for them with a number of different underbodies and keel arrangements.

Are there caveats to your opinion that I missed somewhere?
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Old 06-09-2017, 13:03   #53
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Re: Installing an Inner Forestay

Quote:
Originally Posted by Adelie View Post
It seems to me that other people's experience indicates otherwise.

The Pardey's talk about using a drag device off their bow. That was sprung back so the the boat lay 40* or so off the wind. Their boat was a full keel.

Apparently they did this on a number of boats that they were delivering too so it worked for them with a number of different underbodies and keel arrangements.

Are there caveats to your opinion that I missed somewhere?
Stories of broken rudders due to backing down in huge seas are legion.

The Pardy's boat is a rather unique example of an outrageously overbuilt very small boat.

Some boats have been pulled off of reefs. But that is also very unusual, and I would never include in my storm planning to run a boat up a reef because somebody's steel monster was able to absorb the punishment.

But there is always a caveat with any advice: YMMV. And I will also add this caveat: This is an opinion based on a life time of offshore sailing on small boats and large, power and sail, with over 85000 miles at sea under sail, and another 85000+ miles at sea on powerboats. And this experience put through the lens of a professional life time of engineering boats, airplanes, missiles, and spacecraft, responsible for composite structures, fluid dynamics, electronics and software. Different boats, different people, different storms will lead to different experiences.
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Old 06-09-2017, 13:21   #54
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Re: Installing an Inner Forestay

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Different boats, different people, different storms will lead to different experiences.
This should be the final words on a lots of these CF threads. It should,,,,, become a CF cliché! 👍
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