Adding a jib halyard... mast bend fears..

[groundhog]

I need a jib halyard.
The easiest thing wold be to add an eye/loop up near the top of the mast.
But without an equal support on the back side of the mast, i fear mast crimp due to the forces of the backstay at the mast top and the new halyard pulling forward from just below the mast top.

If I scoot the loop up as high on the mast as possible, I decrease the lever-arm of that force combination.

Are my fears unfounded?

The boat is an albin vega 27, masthead forestay and backstay.
The new halyard will service a 30% storm jib with its own low-stretch line acting as its own forestay.

groundhog

[Faster]

What you're describing sounds more like a stay than a halyard per se..

But in any event I think your fears are unfounded.. esp if you're planning to take this 'halyard/stay' to the top of the rig. I'm going to assume you're doing this outside of a roller furling setup? Are your current halyards internal or external?

A couple of thoughts:

If your halyards are currently external (ie, the main halyard goes up, across two sheaves and down the front; the jib halyard goes up, across two sheaves and down the back) I'd give some thought to converting to internal halyards. That would free up the second forward masthead sheave for a second (internal) jib halyard, eliminating your concerns altogether and avoiding having to hang a block/loop whatever on the mast somewhere. The halyard lead would also be correct, ie under the forestay proper.

The added advantage would be a quieter setup with less halyard slap in a breeze. You'd need to add three exit slots but that's a relatively easy job, as is 'fishing' the (now internal) tails out through the slots. This involves installing some of these:

Isomat Halyard exit plates

If you do this, stagger these exits at least a foot apart, and on opposite sides of the mast to spread them out a bit. I'd also suggest having the exits at least 3-4 feet above the deck to ease the leads to turning blocks if they are to be led aft. If the winches/cleats are on the mast obviously they'll need to be above those.

I do think you'll have trouble getting adequate luff tension on the 'storm jib' that is essentially flying free...

[groundhog]

Thank you faster...
You have answered questions of my other option which is converting my outside run halyards with the 4 sheves to inside run halyards.

The easier thing would be to add an eye or mast hound just below the top of the mast. I am attempting this with the mast up, so work will be at the top, in the cold, and scared. lol. But if method you describe is much beter, i can do that.

I was hoping to just attach the eye up high and do a more complicated solution later if needed.

The boat has a proper furler where i plan to change sails successively smaller as the weather worsens, then have the final 30% storm jib on its own continuous loop furler to be hoisted from the cockpit inside the true forestay. I am planning a 2:1 purchase on this halyard to get extra tension.

groundhog

[SloopJonB]

I'd like to add a couple of my preferences - Fasters comment about exiting the halyards up the mast is correct as far as it goes but I have found I prefer to have them exit considerably higher. This is so a crewman has the option of hauling on them - it gets the sail up a lot faster than only tailing from the winch. I've also found it useful (albeit on a larger boat) when hoisting someone up in a bosun's chair - you can "sway" the halyard and get them up faster than the winch can. I've found internal halyard systems all seem to add considerable friction over the external systems I've used so every extra bit of "purchase" helps.

Next, re: adding a block for an additional external halyard, why not simply add a spinnaker bail or crane to the top of the masthead fitting? A S/S plate the width of the top side of the masthead fitting, with a S/S loop welded to it works well. Just make sure it projects the block enough to clear the existing halyard / headstay. I have this setup on my rig - actually twin bails for two blocks / halyards. The loops are canted out to each side for clearance rather than being projected farther forward. This shortens the loops up, reducing the bending stresses on them. It's worked for 40 years.

[Faster]

Originally Posted by SloopJonB

I'd like to add a couple of my preferences - Fasters comment about exiting the halyards up the mast is correct as far as it goes but I have found I prefer to have them exit considerably higher. .....

Quite agree about higher exit locations, but think it's more of a 35-40 footer issue than a 27 footer... the effort to raise sails on a boat under 30 feet should not require the advantage given by being able to 'jump' the halyard, but even 4 feet above deck at least allows that option to a degree. On larger boats they should exit above one's head.. agreed. The Hunter-esque style of exiting the halyard at the deck step negates this idea....

[Gary M]

If you are cutting holes in your mast so the halyards can exit at the bottom, then make sure you stagger them vertically so that you do not develop a weak spot on your mast. I know of at least one boat that lost her mast that way.

[mitiempo]

SloopJonB

He is adding it for a storm jib which should be inside of the existing forestay/furler - I don't think a spinnaker crane arrangement (which he already has) will work.

[SloopJonB]

Originally Posted by mitiempo

SloopJonB

He is adding it for a storm jib which should be inside of the existing forestay/furler - I don't think a spinnaker crane arrangement (which he already has) will work.

Agreed - I saw that after I posted.

[knuterikt]

Originally Posted by groundhog

--snip--
The boat has a proper furler where i plan to change sails successively smaller as the weather worsens, then have the final 30% storm jib on its own continuous loop furler to be hoisted from the cockpit inside the true forestay. I am planning a 2:1 purchase on this halyard to get extra tension.

groundhog

If you put the new halyard less than 3-6% of the mast height below the masthead you should not need extra back stays (3-6% of mast above deck). That is the way Solent stays are set up.

For a 1:2 purchase you should try to have some distance between the standing part and the sheave/block leading the halyard down to avoid twist in the halyard.

I have used one of these (from Wichard)


To install this you;

• make a slot in the mast
• mark and drill the holes for the pop rivets
• insert the two halves
• bolt them together
• insert the pop rivets

[mitiempo]

I think you mean 3 - 6% below the masthead.