Inner forestay?

[Travelling Westerly]

I'm reading up on inner forestays for a couple of reasons and would like some opinions.

1st is I wanted some support for the area of mast just under the top spreaders. This area suffers from mast pumping and no amount of tuning seems to get rid of it. The mast is a Kemp twin spreader inmast unit with in line shrouds (not swept back), a baby stay and 2 aft lowers. It seems that there is a large section of mast between the lower spreaders and top spreaders that is almost unsupported and that's the section of mast that pumps. There appears to be 2 points built into the mast just below the top spreaders to allow running rigging to be fitted. Everything I've read so far seems to suggest inner forestays are rigged from just under the top spreaders.

The 2nd bit of this is that I thought I already had an inner forestay as I have a removable wire stay from near the top of the mast down to just behind the capstan, about 3ft behind the furling genoa. As this is only about 3ft behind the forestay, what is it?
I've got a good selection of hank on sails and a storm jib that seems to fit this removable stay. However as it's connected to just below the top of the mast it does not provide any support to the top third of the mast and hence does nothing to help prevent mast pumping.

The 2 fittings just below the top spreaders look more like 2 halyard entry points? Can an inner forestay be made from running rigging, not wire?

Lot of questions I know and finally I don't have any running back stays either, just fixed. Not sure if that means I can't rig an inner forestay with no opposing back stays?

Thanks in advance

 

[Gadget257]

1st - depends on what rig you intend, a cutter rig then the inner fore stay attachment may well be at the top spreader or lower and you would require running back stays to stop the mast from pumping. A slutter/solent rig with the inner fore stay attachment very near to the top of the mast would not require running back stays (as the mast won't pump due to the proximity of the back and fore stay).
2nd - Dyneemea is often used for removable fore stays and many yachts use dyneema for their standing rigging.

 

[Travelling Westerly]

1st - depends on what rig you intend, a cutter rig then the inner fore stay attachment may well be at the top spreader or lower and you would require running back stays to stop the mast from pumping. A slutter/solent rig with the inner fore stay attachment very near to the top of the mast would not require running back stays (as the mast won't pump due to the proximity of the back and fore stay).
2nd - Dyneemea is often used for removable fore stays and many yachts use dyneema for their standing rigging.

Ah I see, so the current removable stay I have is a Solent stay.

The thing is the mast pumps badly at present so if I rigged a halyard from the masts inner forestay point to the Solent stays deck attachment point do you think that may reduce the pumping. Surely it can't be any worse than it is already?

I have a set of storm sails, from what I've read the storm jibs are set on an inner forestay which I don't seem to have. I'm wondering if a storm jib can be set on a Solent stay?

 

[Tranona]

Your current inner forestay was I expect fitted to deploy the storm sails. Pretty standard set up. Not sure adding another inner stay will help support the mast without matching running backstays.

Suggest you speak to Selden about the rig (they took over Kemps) or one of the big riggers like Allspars for advice.

 

[Travelling Westerly]

Your current inner forestay was I expect fitted to deploy the storm sails. Pretty standard set up. Not sure adding another inner stay will help support the mast without matching running backstays.

Suggest you speak to Selden about the rig (they took over Kemps) or one of the big riggers like Allspars for advice.

Thanks Tranona

I'm speaking to my Rigger at the moment. The mast has 2 rollers/points for running rigging at the point just below the top spreaders but no points for a set of running backstays. I've looked around at the other Westerlys in the yard and they don't even have a Solent setup let alone an inner forestay for ideas.

So it looks as if my storm jib will run up the Solent/removable forestay then.

My thinking about rigging a halyard to the inner forestay point on the mast was really to pull that section of mast forwards to stop this blooming mast pumping. It's really getting on my nerves now. I can't see any other way of stopping it. It seems to be such a big mast with not much support in that section around the top spreaders.

 

[PetiteFleur]

Have you put this question to the Westerly Owners Association? I'm sure you will get your answer.

 

[Supertramp]

A furling mast is a solid piece of kit and Westerlys sail the world implying the design is robust and used in many boats. Assuming mast and rigging is as originally specified, it sounds like a setting up problem and I would start by checking with your rigger and WOA how the babystay and lowers should be set up relative to the fore and back stays, based on Selden tensioning figures. I definitely wouldn't start bolting on more forestay and backstays until I was sure the basics were right.

A Solent stay is a useful thing and being able to use hanked sails is a good heavy weather option (but not if your mast is pumping!!).

 

[Travelling Westerly]

Have you put this question to the Westerly Owners Association? I'm sure you will get your answer.

Oh dear, I'm going to get shot for this but here goes....... I'm not in the WOA ? any longer. Didn't really find it useful. When I did have questions it proved fruitless so I cancelled my membership. No doubt I'm in trouble now ?

 

[Travelling Westerly]

A furling mast is a solid piece of kit and Westerlys sail the world implying the design is robust and used in many boats. Assuming mast and rigging is as originally specified, it sounds like a setting up problem and I would start by checking with your rigger and WOA how the babystay and lowers should be set up relative to the fore and back stays, based on Selden tensioning figures. I definitely wouldn't start bolting on more forestay and backstays until I was sure the basics were right.

A Solent stay is a useful thing and being able to use hanked sails is a good heavy weather option (but not if your mast is pumping!!).

I agree with you 100% but after trying several different riggers, reading Seldens tuning guide many times over, reading just about all Internet posts ever posted discussing mast pumping, hoisting fenders up the mast, having a Selden replica mast track tape made to disrupt the vortices and finally renewing the standing rigging only 3 months ago I'm at a loss on how to stop it.

The strange thing is it only happens between 5 and 10 knots wind speed in a certain wind direction whilst alongside my home berth.

The boat has been half way round the world (previous owner) so it, as you say, must be strong enough. I just can't accept it as it is, it drives me nuts at night. The aft cabin is like a bouncy castle when it gets going.

 

[Supertramp]

Oh dear, I'm going to get shot for this but here goes....... I'm not in the WOA ? any longer. Didn't really find it useful. When I did have questions it proved fruitless so I cancelled my membership. No doubt I'm in trouble now ?

Don't panic, you still have your rigger and Selden...... but seriously your rig set up appears on loads of boats so you could pretend it's a Moody or similar. Although many have swept back spreaders which will help keep tension on the mast.

 

[dunedin]

Oh dear, I'm going to get shot for this but here goes....... I'm not in the WOA ? any longer. Didn't really find it useful. When I did have questions it proved fruitless so I cancelled my membership. No doubt I'm in trouble now ?

A close look at, and/or photos of, the rig of an identical sistership would be the best way to find out how the boat should be rigged. So perhaps a kiss and make up with the WOA would be a good idea

We have a very different boat and rig setup, but I find we need to leave a bit of backstay tension on to pretend the mast slightly, to avoid mast pumping in very string winds. Is your mast setup with any pre-bend?

 

[Travelling Westerly]

A close look at, and/or photos of, the rig of an identical sistership would be the best way to find out how the boat should be rigged. So perhaps a kiss and make up with the WOA would be a good idea

We have a very different boat and rig setup, but I find we need to leave a bit of backstay tension on to pretend the mast slightly, to avoid mast pumping in very string winds. Is your mast setup with any pre-bend?

Kiss and make up - I like that ? Good WOA sales pitch ??

When I first bought her the mast was slightly inverted, bad I know but she never pumped.
Riggers put in a slight pre bend and it seemed to do the trick. Unfortunately that amount of pre bend caused the inmast furling to bind and cause the final bit of mainsail furling difficult.
We then straightened the mast which had the sail going in and out like a dream but pumping came back. Had the rigging replaced 3 months ago, started off straight mast but pumping was horrendous. Slakened the rigging and put some prebend in (very small) and pumping seems to occur lower down the wind range now.
I can see it happening. The section just below the top spreaders moves fore and aft, it's not massive but once the vibration travels down the back stay and into the aft cabin it feels much worse. The halyards and cables inside the mast rattle badly as well which makes the whole situation feel worse.

I found an old Westerly Owners manual which discuses rigging and even mast vibration. It suggests tighten up on baby stay and aft lowers, anti vibration strip up the mast and finally additional wire forestay. It's the additional wire forestay that I feel gives a bit of weight to my idea of running a temporary halyard as an inner forestay when alongside. A bit of forward tension only whilst alongside may keep that section of mast under forward support and hence stop the pumping?

 

[Supertramp]

I agree with you 100% but after trying several different riggers, reading Seldens tuning guide many times over, reading just about all Internet posts ever posted discussing mast pumping, hoisting fenders up the mast, having a Selden replica mast track tape made to disrupt the vortices and finally renewing the standing rigging only 3 months ago I'm at a loss on how to stop it.

The strange thing is it only happens between 5 and 10 knots wind speed in a certain wind direction whilst alongside my home berth.

The boat has been half way round the world (previous owner) so it, as you say, must be strong enough. I just can't accept it as it is, it drives me nuts at night. The aft cabin is like a bouncy castle when it gets going.

I have had a similar thing but only in much stronger winds. My mast behaves differently when the in mast main is removed with more rattling and general vibration. Experiment with things like halyard positions and tension and topping lift tension - I wonder if vibration and oscillation in rigging or halyards are then making the mast vibrate. Excuse my ignorance - I assumed the problem was when under load sailing.

 

[Supertramp]

I have had a similar thing but only in much stronger winds. My mast behaves differently when the in mast main is removed with more rattling and general vibration. Experiment with things like halyard positions and tension and topping lift tension - I wonder if vibration and oscillation in rigging or halyards are then making the mast vibrate. Excuse my ignorance - I assumed the problem was when under load sailing.

Just read your last post - yes, a temporary piece of rigging to change the tension and vibration characteristics sounds sensible.

 

[dunedin]

Just read your last post - yes, a temporary piece of rigging to change the tension and vibration characteristics sounds sensible.

Certainly sounds very cheap and easy to test.

 

[Travelling Westerly]

I have had a similar thing but only in much stronger winds. My mast behaves differently when the in mast main is removed with more rattling and general vibration. Experiment with things like halyard positions and tension and topping lift tension - I wonder if vibration and oscillation in rigging or halyards are then making the mast vibrate. Excuse my ignorance - I assumed the problem was when under load sailing.

No excuse needed, appreciate your help ??.
The pumping only ever happens alongside. I down slacked all halyards including taking the topping lift off the boom and spiralling it around the back stay in an attempt to isolate the possibility it was the back stay oscillating under the wind. Strangely that worked for a while, but now the pumping has returned and I can see the mast moving.

 

[Travelling Westerly]

Ha, I think we are all replying at the same time so my last post got a bit crossed over.
I'm going to climb the mast when it stops raining and try my temp inner forestay/running rigging idea. ??

 

[[2574]]

Had a similar problem on our NautIcat’s Selden inmast rig. Consulted Allspars who found that the rig OEM specified checkstays that had been removed. Refitted checkstays and problem disappeared.

 

[Travelling Westerly]

Had a similar problem on our NautIcat’s Selden inmast rig. Consulted Allspars who found that the rig OEM specified checkstays that had been removed. Refitted checkstays and problem disappeared.

Hey Rob, I wondered if something had been removed rigging wise too. It seems a big rig with very little support a third of the way up. Very much like something is missing. If you grab the cap shrouds and jiggle them around you can hear and see the whole rig move!

Thing is I've had riggers carry out inspections and new rigging just done, they agreed it moved a bit but said a big rig with in line spreaders will do that.

I've checked deck fittings to see if anything is spare but nothing. Also checked other Sealord and Oceanlords, all have the same set up. The only thing that made me wonder was the 2 pulleys mounted in the mast below the top spreaders for an inner forestay I'm guessing.

 

[William_H]

One would not expect pulleys on the mast to be used for running back stay attach. More likely just ordinary stay attachment.
A bit confusing to me when you use the term mast pumping which would occur when sailing indicating inadequate mast column support. it seems more like what I would call vibration of the mast in wind when moored. This latter might be cured by more mast support and yes more mast support might be needed anyway.

In line spreaders do mean there is not much fore and aft support for a mast middle. Running back stays can provide a pull back to the mast middle. But they can be very tedious if you do a lot of tacking. Another fix not so often seen is diamonds. A small set of spreaders angled forward 45 degrees mounted in the middle of the mast or span of concern. Wires run from above ie top of mast to below ie bottom of mast providing push back of the mast at the base of these diamond spreaders. Typically used to support the top half or section of mast. If you can get the spreaders to angle aft even a little against in line cap shrouds will provide some push forward. Usually however angled back spreaders are sued in conjunction with intermediate stays to chain plates aft of abeam the mast. Similar effect to diamond spreaders. ol'will