Poling Out Genoa Using Boom ... End Fitting ?

[akio.kanemoto]

Greetings Folks,

I want to use two headsails downwind - one poled out with a spin pole and the other I want to use the boom itself.

I've read in a variety places that a lot of people do this - but I can't find any details of how/where to attach a fitting to the end of the boom that the genoa sheet goes through.

Even Evans Starzinger made a post here a while back stating that he just uses a piece of PVC hose (!) so besides the point that I can't imagine how that works, it appears that there are many variations on this.

So can somebody shed some light on this for me?

I just can't think of a way to attach a block or whatever to the end of the boom so it behaves like a spinnaker pole's jaw. Do you fix it under the boom? (perhaps to the bails which hold my mainsheet blocks (end boom sheeting)) To the aft end of the boom somehow?

I also have a spectra lashing going around the circumference of the boom (about a foot from the end) where my preventers are made off to... perhaps a block can be shackled there...? But then it would be below the boom again and won't it chafe?

I am totally confused.

Thanks!

[msponer]

I think Evans system is cool -- easy, simple, and effective. There is a photo of it in one of their books. The gist is that they lash the PVC hose to the bottom of their boom towards the end, then run the jib sheet through the PVC hose. I'm not sure there's much more detail to it than that.

I have used two headsails quite a bit, and was happy with just one pole and nothing on the boom. It was easily good enough. The second pole or boom trick would keep the second jib in a better shape, for a bit more speed, and keep it from collapsing and backwinding. But we were happy to head up a few degrees from dead downwind if the jib was collapsing, and ... did not feel like we were losing that much speed-- the second jibs shape was not that bad.

[belizesailor]

Amels have an unusual twin-headsail, twin-pole, down-wind rig. You might look at those for some ideas too. Owner's I've talked to really like the arrangement.

[Valkyrie654]

This is what we do and have found it to work vary well. We have a pad eye on the bottom of the boom at the very end. The farther out the better, though i can see how a spectra chocker could work as long as it does not bind on the outhaul. To this you can shackle a good strong block such as a Harken ESP with a becket. Depending on the size of your boat either the 57 or 75 mm. Very high working strength, low friction and not that much money when you consider the performance you are getting out of them. We use the 75 on our 44 foot cutter. You attach the preventer to the becket. The genoa sheet is run as follows. From the clue through the block on the end of the boom. Then back forward to a good strong place on the rail. We use a spectra loop through our #2 mooring fair lead, which is just forward of the forward lowers. The exact placement is not all that critical. To the loop we have a snatch block. This then turns the sheet aft where it then goes to the winch in the usual manner. This "z" in the sheet does two thing for you. 1. You have no chafe along the bottom of the boom. 2. The sheet tension act like a preventer of sorts, though not totally. In heavy air we still use the preventer. If you find that the the sail is sheeted in too high, ie. too much twist, like we have, you can attach a 4:1 fiddle block tackle, with a cam cleat to the clue and take this to the rail. Pull this tackle down until you have the proper amount of twist into the sail. We find that with our 155% genoa the clue is a foot or two forward of the boom. Even when running deep angles, by keeping the slot open, you are actually able to generate some lift out of the main. This in turn means that the main is not as far out as that wind angle would usually have been. The real key to getting to all work is the poled out jib to weather. Without that sail directing wind into the genoa, which in turn gives you air flow behind the main, it will just hang there as limp as a rag and you are all so slow. We find that we can also fly our staysail to leeward and it also gives us more speed. A real nice benefit is that the sail plan is so balanced, the helm is as light as a feather. It takes some time to set this all up, but for longer runs where you don't have to gybe very often it is just a wonderful set up. I will work on finding some pictures of this all set up and just flying along.

[akio.kanemoto]

Thank you for the replies!

On both solutions (block and pvc hose) - just to confirm - there is a THIRD jib sheet involved right? So to set up, you run through the boom end, while the "normal" sheets are still attached and active.. then you crank on the new end-boom sheet while easing the "normal" sheet?

Valkyrie, on my boom, the spectra strop is around a foot from the end, so it's not in the way of the outhaul. It's secured from moving fwd/aft on the boom by passing through a bail under the boom to which the mainsheet block attaches to. It still can go "diagonal", but can't move beyond about 10cm/4" fwd/aft.

On the "z" arrangement - just to confirm, the reason you cite for "no chafe along the bottom of the boom" - is that because it pulls the sheet DOWN as well, therefore ensuring that the sheet rides on the sheave of the end-boom-block properly? Where does the sheet want to go if not led down and forward as in your "z" solution?

On preventers, I have a dual-purpose line on my foredeck per side, to act as a pole downhaul and also a preventer. I also have afterguys rigged on both sides as well, all going to clutches, so if the solution requires it - I can lock up the boom or pole completely in place independenty of the sheets.

[Valkyrie654]

You could use a third sheet, but it is not necessary. You can either run the sheet to the end of the boom before you unfurl the Genoa. The third sheet is not a bad idea in so much that you can just cast it off and sheet in the standard sheet to quickly get the sail off of the end of the boom.

If you were to run the sheet from the end of the boom straight to its turning block you most likely get chaif on the sheet where it rubs non the boom. Unless you had a fully articulating turning block I don't see how you could avoid an unfair leed to the winch, resulting more friction an chaif.

[akio.kanemoto]

Originally Posted by Valkyrie654

You could use a third sheet, but it is not necessary. You can either run the sheet to the end of the boom before you unfurl the Genoa. The third sheet is not a bad idea in so much that you can just cast it off and sheet in the standard sheet to quickly get the sail off of the end of the boom.

If you were to run the sheet from the end of the boom straight to its turning block you most likely get chaif on the sheet where it rubs non the boom. Unless you had a fully articulating turning block I don't see how you could avoid an unfair leed to the winch, resulting more friction an chaif.



Attachment 37513

Thanks for that - greatly appreciate, I get it now! If the load is mainly down, with the Z arrangement, I can easily attach an additional block under the boom at the end (basically I have a "slot" where slugs with "bails" go into the boom underneath) and take it forward per your idea.

Just out of curiosity - do you use a topping lift on your boom to provide support when using it as a pole? I have a rigid vang, so don't use a topping lift - but was thinking that the additional support could be neccessary?

[Valkyrie654]

Our rigid vang supports the boom without the use of a topping lift, but the wind pressure on the sail will pull the boom up once you get past the end of the traveler. The further the boom is eased the less the main sheet will be able to keep the boom down. The wind pressure will pull the boom up, increasing the twist in the main. Also the boom will pump up and down as the wind speed varies. This in turn will allow the sail to slide up and down on the standing rigging increasing chafe on the sails. This in now the time to pull the vang on good and tight to keep the boom down, and stop the pumping. You can also use the vang to control the amount of twist in the main. Too much twist, and you are just throwing away useful sail area. You need a powerful vang to control the main. A block and tackle from the middle of the boom to the rail is not a good way of holding the boom down, that is a good way to break the boom! On our 44, running about 450 square feet sail area, our vang has a compound tackle yielding 8:1 advantage, then to a #40 winch. I would not want anything less. A vang is a very important piece of equipment, often over looked on cruising boats.

[akio.kanemoto]

Originally Posted by Valkyrie654

Our rigid vang supports the boom without the use of a topping lift, but the wind pressure on the sail will pull the boom up once you get past the end of the traveler. The further the boom is eased the less the main sheet will be able to keep the boom down. The wind pressure will pull the boom up, increasing the twist in the main. Also the boom will pump up and down as the wind speed varies. This in turn will allow the sail to slide up and down on the standing rigging increasing chafe on the sails. This in now the time to pull the vang on good and tight to keep the boom down, and stop the pumping. You can also use the vang to control the amount of twist in the main. Too much twist, and you are just throwing away useful sail area. You need a powerful vang to control the main. A block and tackle from the middle of the boom to the rail is not a good way of holding the boom down, that is a good way to break the boom! On our 44, running about 450 square feet sail area, our vang has a compound tackle yielding 8:1 advantage, then to a #40 winch. I would not want anything less. A vang is a very important piece of equipment, often over looked on cruising boats.

Thank you again for your detailed reply!

On the twist in the main etc - I was thinking of running without the main actually - so just the two headsails out.

I have one 135% genoa on a furler and will roll that up to around 100-110% and I have a Code Zero continuous line furler which I will be buying a sail for (I'm thinking 100-110% so I have a balanced "no brainer" setup).

You mention that the sail pulls the boom up when the wind pressure increases - I'm assuming that you're referring to the standard mainsail's behaviour - since the genoa sheet is now led down and forward with your "Z" solution (sounds like a great brand name too

I would have thought that the down-and-forward pull on the end of the boom would have been enough to keep the boom down though without needing a vang as well?

(on the requirement for vangs, actually I have quite a powerful one - it's a cascading setup - can't remember the actual purchase, but it's something like 16:1 or so)

[Valkyrie654]

Our outer jib is a 155%, and the inner jib is 110%. They work quite well together. your 135/110 should also work just fine.

You will get a bit of downward force from the "Z", but really not all that very much. Because of the block, the actual direction of pull is the center of the angle that sheet makes as it goes through the block. It is mostly a forward pull. At least the the way we have ours set up.

Why not fly the main? It not only gives you a lot more area, thus speed, but the rig is so well balanced that a wind vane will have no trouble steering the boat. Actually the center of effort is so far forward, she sails like she is on rails and just steers herself. With our three head sails and main set, we are almost 2,000 square feet of sail area. The photos above were taken in 12 -15 knots apparent and the boat was moving right along in the low 9's. No complaints from us on that considering that we displace about 47,000 lbs.

Your 16:1 vang should work out well for you.

Go sailing and let me know how it all goes.

[bobconnie]

I have always used the spinaker pole on the off side jib and the roller in the normal manner and just point off a bit ! sails easy and you can shape the main to aid the wing and wing jibs that way !! lot more comfortable ride bearing off a bit keeps the "jerks" from happening ! LOL much smoother. just my 2 cents Bob and Connie