Setting-Up In-Boom Outhaul for New Loose-Footed Main - Any Advice?

[Northeaster]

Hi folks,

I am finally breaking down and buying a new mainsail for my 1978 Seafarer 30. The old main is likely at least 15- 20 years old (and could very well be original). Boats are only in water about 4 - 5 months a year up here, and i have only owned her for 3 years.

The old main was NOT loose footed and had no outhaul. The clew was just attached to the end of the boom with a shackle.

As the new main is loose footed, I will need to set up an outhaul. As i am reasonably handy with tools, and have the boat inside a heated shop in the winter, I figure I will modify the boom to set up an in-boom outhaul.

The main is relatively small, luff 32 ft, foot 9.5 ft, so it is not too hard to control. The harken site show either 5-1 or 6-1 in-boom outhaul systems.

I am just wondering what purchase ratio I would need, and what size line would be best, so I can source the proper blocks, etc.

I am thinking of something like this: (5-1, or 6-1)

http://www.harken.com/rigtips/outhaul.php

Any input would be appreciated!! Thanks in advance!

[delmarrey]

I have two out-hauls in my boom of 17' w/ loosefooted sail 16'. I have a track and car on the last 6' of the boom, a bit like a in mast furling. (explain later)

The foot is 6:1 purchase using a clew block and the first reef is 4:1. The second reef I just switch up from the first. I really need a 7:1 but it creates sooo much line. On yours a 5:1 would probably be OK.

What you have to look out for are screws or rivets sticking inside boom. The lines and blocks can hang up on them. Blind rivets are best, for the inside piece is a bit rounded.

Another point is to use a fairly stiff line that will not twist causing the block to jam. Hopefully you can see inside the mast. My old mast had cutouts along the sides and used wire lines inside the boom only. This new one I can see all the way forward though the aft casting.

I use the car to advance the clew forward which ballons the sail like a jib and I never let the boom out more then 45º for safety reasons.

[bewitched]

An alternative approach if you have cabin top halyard winches:

Take a look at each end of the boom - how many sheaves are there at each end?

If 4 - Get a main made with 3 reef points and use the 4th sheave for the outhaul. Run outhaul to cabin top halyard winch - you will need a rope jammer or cam cleat to secure. No need for any purchase system in boom. If winches aren't up to it, you may achieve a 2:1 by running the outhaul up out of the sheave on the aft end of the boom, through a suitably sided block attached to the clew (or similar built in arrangement as per Delmarry's sail) and then back to a shackle attached to the aft end of the boom (where Delmarry's topping lift is attached to)

If 3 - as above, but get a main made with 2 deep reefs and use the third sheaves for the outhaul.

If none - the Harken option

[Hydra]

Northeaster,
The size of my loose-footed mainsail is similar to yours, about 13' foot and 36' luff. The setup is close to what bewitched has described, except that the winch for tensioning the outhaul and the reef lines is on the mast, under the gooseneck. There are 4 sheaves at each end of the boom and the rope jammers are part of the gooseneck. No purchase/tackle is necessary, the winch is powerful enough when using a long handle.

Alain

[Northeaster]

Thanks for the advice so far!

Delmarrey - good advice. I will be taking the aft end off of the boom this weekend, and will be able to see inside fr things such as screws or bolts sticking out. There are a couple of things on the boom (small track on side for reef outhaul, padeye on other side, etc)

Bewitched anbd Hydra - thanks for the advice. Unfortunately, my boom has no sheaves in it, as there has never been any lines run in boom before.
I do have cabintop winches with quad organizers and clutches on each side, but these are quite full with things like:
- main halyard
- jin halyard
- vang
- 2 lines for 1st reef
- 2 lines for 2nd reef

I am sure that I could use the clutches for other purposes, but I really like the way I can reef easily, from the cockpit.

Therfore I think that the Harken style, in-boom system, with a line and cleat on the side of the boom, would work well for me.
However, there is a wide assortment of blocks available, and I am not sure what tyoe of working load or breaking strength I would really need, with such a small mainsail.

It looks fairly easy to cut out a small slot in the top, aft end of the boom, for the wire block / sheave, and then another on the side, for the line to exit. I would mount a cleat next to this hole, to secure the line with. Sine I would not be using a winch, I do think I would need something like 5-1 or 6-1.

Anyone have something similar setup?

Here's a couple of pics of the current setup:

[svTOTEM]

Instead of wire, consider using 1/4" Amsteel (spectra). As long as the lead is fair with no chaffe, spectra line is easy work with and probably cheaper than wire. I replaced my wire with Amsteel 2 years ago (boom is 18') and it works great.

[thinwater]

I have had both, and internal rigging is not perfect. I could go either way. Inside is cleaner looking, but painfull if birds or wasps decide to nest in the boom.

[Northeaster]

Totem - I was only going to use wire for the small length from the clew, down though the recessed block in the top, aft end of boom, to the double or triple block. Then there would be line between, around the pulleys of the blocks and exiting out a recessed block in the side of the boom, to a cleat. Not sure of the line size needed for strength, but I was thinking of something a bit larger than 1/4", so it would be easier to grasp and pull to tighten. Thought it might be easier on the hands than a thinner line, although the thin line may have enough strength.

Of course, the larger the line, the larger and more expensive the blocks needed.

Thinwater - I would prefer to keep the blocks / , 5-1 or 6-1 purchase inside the boom, not so much for a clean "look" but moreso just to keep the clutter down. Good points about insects, nests, etc. I amy also put a small tarck and adjustable block on the port side, similar to the starboard side, in the pic, so my 2nd reef has an adjustable point of attachment on the boom. May be overkill though.

[Shoalcove]

Hi Northeaster, Nice photos. We sail around Chester Basin as well. I just went to a loosefooted Main and have the setup you are describing. I used spectra line from the sail to the outhaul blocks because it is easy to handle. Inside the boom I used normal yacht braid. I don't think the loads are that great on the outhaul. I seem to remember there were calulations on the Harken Tech site to determine loads.
Best regards,
Shoalcove

[Northeaster]

Shoalcove - thanks for the advice! We are certainly spoiled (in the summer) with great sailing and reliable winds. Luckily, I do enjoy the winter as well, skiing and the like, as it would be a long wait till lauch otherwise!

Take care!

[Hydra]

Northeaster,
From your pictures, I am not sure that there is enough space to put a sheave and tie a knot on the outhaul beween the clew on the mainsail and the end of the boom.

Also keep in mind that the foot of the sail will stretch when you tension the outhaul. My boom is probably 8" longer that the foot of the sail.

Alain

[Northeaster]

Hi Alain,

I will not require a knot between the clew and the end of the boom.
The plan is to use one of these:

Product Details

A thru-deck block - The wire will be shacked (likely) to the clew, and the wire will run directly into the aft end of this block, which lets the wire enter inside the boom, and connect to the 1st double or triple block.

Your point is well taken though, that I do require a few inches of room from the clew to this block. My sailmaker is getting me to measure the total boom length, from the mast, this weekend. He will then reduce by the necessary amount, when making the new sail's foot length.

I know it would be alot of work, but I wonder how much it would affect my boat's performance, if I increased the boom length by a foot or two????

[Shoalcove]

Northeaster,
Hydra may be right about the space available. If it isn't too late your sailmaker can allow for that. If not, you may be able to shackle a block at the end of the boom and run your lines outside your boom this year to experiment with the purchase you require to tension things properly. I've got to do some fiddling with mine this spring as well to fit my new main.
It's been a pretty good winter but I'm looking forward to getting down to SSM to get some projects going. It won't be too long now!
Cheers,
Shoalcove

[Hydra]

Northeaster,
Considering the cost of the modification that you intend to do, I suggest that you begin with a full-scale drawing, just for checking that everything is OK.

About increasing the boom length, if you also lengthen the sail foot, you will certainly increase the sail area but also move aft the center of effort. This could increase weather helm. Of course, lengthening the boom probably means changing it for a new one and hoping it will fit on the old gooseneck.

Another detail that might be of interest for you: at the clew on my mainsail, there is a loop of webbing (2 turns, closed with Velcro) around the boom, instead of a bronze slider in the boom that appears on your pictures. In my experience, this is most convenient when removing the sail from the boom, because I don't have to pull the slider along the boom to the tack.

Alain

[delmarrey]

Originally Posted by Northeaster

Hi Alain, .............

Your point is well taken though, that I do require a few inches of room from the clew to this block. My sailmaker is getting me to measure the total boom length, from the mast, this weekend. He will then reduce by the necessary amount, when making the new sail's foot length.

I know it would be alot of work, but I wonder how much it would affect my boat's performance, if I increased the boom length by a foot or two????

Increasing the boom length will not change your performance but you will need to clear the backstay or be concerned about head room. Without seeing the whole rig it's hard to make an assessment. I added an extra foot to my boom to accommodate the track and car.

Also the placement of your main sheet blocks and traveller should be at the end or near the end of the boom with a loose footed sail. If mounted in the boom center, an accidental jibe could brake the boom from bowing it suddenly. The stresses on a loose footed sail are at the ends (clew and tack).

And a boom with a loose footed sail tend to drupe. So you'll need a semi-rigid vang (spring loaded or gas/hydraulic) to support the boom. A topping lift helps with managing with the sail flaked but has to be loose when under sail. This is why I went with a car and track. If you ease off on the outhaul the boom will lower if not supported by a semi-rigid vang. With the car I can shape the sail as I want w/o worrying about the boom. BTW the car also has a position line to place the clew on the boom where I want it.

This may sound perdy complicated but I can fine tune the main. When on the reefs I sail it like an in-mast furling.