Downhaul for Spinnaker Pole

[MrFish]

We sail a 37ft (11.3m) fin keel sloop, with a fairly large spinnaker.
We want to increase the purchase on the spinnaker pole down haul, to improve our ability to control the spinnaker by holding the pole right down low.
At present we have a continuous line from the cockpit, up one side of the boat to a turning block on the centreline of the foredeck, up to the turning block on the pole, back down to the 2nd turning block on the foredeck, and back down the other side of the boat to the cockpit. We have clam cleats each side at the cockpit. We don't have a winch available, and haul in on the line by hand.
We have in mind to put a double block on the pole, and another block on the foredeck (making 3) to increase the power of the down haul. We are a bit nervous about the likelihood of a tangle when end for end jibing the pole, or while setting up for a hoist.
What other ways are there of increasing the power of the down haul?
How do you work the spinnaker pole down haul on your boat?
All and any ideas & suggestions welcome!
cheers from New Zealand

 

[Adamastor]

Firstly, I'd be wary of end-for-ending the pole if you haven't got a bridle with the downhaul in the middle of the pole. At 37', unless you've got something like a teenager as the "runt on the front" I'd stick with dip-pole and twin sheets and guys in anything over 10kn(T), just because of the safety element. IMHO, teenagers are great up front because they don't get scared doing foredeck obstetrics, and if an end-for-end goes sour, they are likely up there for a while!
If you can't do the job with a winch, then purchase works for me: Id suggest that the new middle block on the foredeck has a snap on it, and that the pole block (or double, as you suggest) has a spectra strop with a snap on that. The idea for the strop is that it gets the blocks away from the pole if the pole goes anywhere near the fence/pulpit, and the snap makes it easier to get the downhaul out of the knitting when you stow the pole. I like to stow the pole "made" with the lazy sheet and guy in the jaws, and keeping the downhaul out of the mix is REALLY useful!
The reason for the snap-on middle block is that if you brace the pole forward for a long reach, you move the middle block to the foreward rail or a forward cleat so it assists the guy- the rag will act as a very adequate forebrace!
Also, if you ever get into Asym kites, the forebrace/downhaul will act as the tack purchase for the tack of the Asym. The Asym then gets a pennant on it that connects to the pennant of the forebrace so you have 4:1 purchase there too!

 

[dt4134]

Do you have problems at the moment moving the genny across in preparation for re-hoisting it? If so, or if the new arrangement looks likely to make that slower, you might want to look at a snap shackle to attach the block to the foredeck so the genny can be slid under it.

The snap shackle also makes it easier to remove any twists you get in the reeved downhaul. It does happen but a good bowman should be able to keep it under control. Should at least be possible to easily untwist it between races.

I don't think a winch, as suggested, would be practical. Depends how actively you trim the guy on your boat, of course, but you'd often want the downhaul uncleated and held in somebody's hand for significant spells.

As an alternative suggestion, you could look at a 2:1 closer to the cleat, but I've not experienced that arrangement myself so I don't know what the pitfalls are.

 

[flaming]

Interesting that you're using an end for end pole...

I do quite a lot of sailing (work...) on the Sunsail fleet who have end for end on that size of boat, and quite frankly it's a pain in the bottom.
I also race on an Elan 37 set up for dip pole gybing with the exact downhall setup you describe, but obviously the downhall at the end of the pole. This is more than enough.
Gybing's much faster too.

If you absolutely must stick with end for end, then play with the size of the bridle as a first step. A longer bridle does mean you can't fly the pole as low, but reduces the load on the downhall as it gets closer to the same angles as the dip pole "downhall at end of pole" setup.

That said I can't think of any reason why you couldn't just add another block, just seems like a slightly unnecessarily fix to me.

 

[sailorman]

we have a 37 ft one tonner with similar set-up to yours except that the line lead aft goes onto a winch on the cabin side abaft the window & just forward of the primary winch

 

[chewi]

I don't sail bots of that size, so my suggestion here is not based on that kind of experience. Nevertheless if you stop the deck end of your downhaul in a free block as far forward as practical, you could take a line fixed at the winch endforward through the block and aft back to the winch to double your current purchase, but you may not have the free length on the deck head between turning block and winch to get enough scope on it.
Just an idea for the pot.

 

[Krusty]

[ QUOTE ]
..................and back down the other side of the boat to the cockpit. We have clam cleats each side at the cockpit. We don't have a winch available,............


[/ QUOTE ]
My boat is not your size but I have a downhaul back to a clam cleat on the cockpit coaming, positioned and aligned to allow the tail to be wound on a winch, then eased with a finger-press to ensure that it stays gripped by the clamcleat; just in case the winch is needed for another purpose such as cross-winching.
If your downhaul has a tail on each side, could you re-position the clamcleats to align with sheet-winches? (Assuming you are not using the windward one when under spinnaker)
Perhaps I am missing something?

 

[William_H]

If the downhaul connects to the middle of the spin pole you effectively halve the purchase (of the power at the tack. If you run the downhaul from near the base of the mast you effectively reduce the purchase even further because the pull angle is not straight down.
I use on a much smaller boat 2 seperate down hauls each to the end of the pole and each from a point on the gunwhale mid way between bow and abeam mast. An added bonus is that i have knot in the downhauls to limit the height of the pole even if the downhaul is not cleated.

The disadvantage is that when end for ending the pole in a gybe you must attach the new downhaul and remove the old but as a down haul it works well.

Incidentally you mention needing to pull the pole down tight. Spins should not be pulled down tight down low. If you pull it down low on a reach the luff will get a hook in it which will cause it to luff earlier. On a reach raise the pole free off the luff and it will set at a closer angle to the wind and with less tension on the sheet. Unlike a jib. I have met many who don't agree but it is very clear on my spins so try it.
When running square the luff can be tensioned down to put a hook in the leading edge (luff) to make more of a cup shape to hold the wind but I don't think this is very valuable.
Funny when I started using spin I felt I needed more power in the downhaul now it seems like the least concern when flying the spin.

The best way to learn spin handling is to get a small spin ie full height but short along the foot.

If it is the death (rhythmic) rolls that are bothering you when running square just sheet in harder and also pull the brace back.

I may have misunderstood you but pulling the pole down hard is not IMHO any use. good luck olewill