MERLIN ROCKET FORUM

Topic : one string does all spinnaker

Can anyone help me here. I converted my spinnaker system to the one string does all way but have had to take it off. The reason was that after a couple of launches the bungee return cord had "wound up" and jammed the whole system. During this winters refit I would like to put it back. Any solutions?


Posted: 26/11/2016 17:36:27
By:
Pictures would probably help, showing the way the system was setup, or a clear sketch?  Is it a pump system to raise the spinny, or the pole launch system that screwed up?
 
I'm not sure what it is you have on your boat and how it might have gone wrong without a bit more information - our spinny raising system is pretty basic (probably for that reason) and I don't see many other systems in use. As for the pole launch system, they do need fettling but generally are pretty reliable once the elastics of the right diam /length  are used. 
Where do you usually sail? 


Posted: 04/12/2016 19:50:41
By: Kieron Mason
I have thought a bit about what you are referring to here, as it isn't very clear.
 
 
Firstly, I think that you are referring to the Spinnaker Halyard being both the uphaul and downhaul.
Secondly, have you set up an elastic system to pull the spinnaker back under the foredeck once it has been dropped?
 
The first one is the standard set-up, leading the spinaker halyard round the back of the centreboard case so that the helm can hoist the kite.
 
The second one is a solution that is not fitted to many boats, but I have found very useful.  On the end of the elastic that we use is a small block that the spinnaker downhaul passes through (not attached to).  This elastic then passes through a bullseye attached to the underside of the foredeck on the crossbeam that is halfway between the forestay and the mast step.  It then proceeds forward to a block under the Jib Tack fitting. Next it runs back along the other side of the boat (to the spinnaker) to the shrouds where it can be secured or passed round another block and led back forward to give it extra length.
 
In use this system doesn't do anything during the hoist or flying, it only comes into use when the spinnaker is being dropped, where once the spinnaker is fully dropped it then pulls the spinnaker back under the foredeck from the cockpit.
 
Hope that this makes sense.


Posted: 09/12/2016 01:21:53
By: Stuart Bates MR3615
I have had a much simpler version of this on my boats for years - a plastic ring the downhaul will pass through but not the kite on a bit of shockcord that goes under the foredeck to a bullseye then to an attachment point under the foredeck.  It doesn't pull the kite back much but it is enough to stop it going through the jib blocks.


Posted: 09/12/2016 17:05:15
By: Andrew M
We use a similar system Andrew - the return elastic starts off at or near the rear edge of the foredeck (tied  off on the barber hauler fixings under the deck actually) and from there goes up to the chute,through a block and back through a bullseye in the deck support beam, and ends in a plastic ring (We tie off a stopper at about 300mm to stop the plastic ring going all the way back to the bullseye)
 
The spinny downhaul goes through the plastic ring and the spinny can more or less reach the thwart/console before it pings back under the foredeck. Its always worked for us.
 
However, I think the OP is on about the pole launch system - some systems had elastic inside the poles which may be the issue, but maybe we'll never know! 


Posted: 09/12/2016 20:23:27
By: Kieron Mason
Andrew/Kieron
 
 Yes my system is the same as yours in principle, I was just being technical on how it is rigged.  I have a block, rather than a bullseye as I had one lying around and it works great in light airs by keeping the downhaul off the tank thus helping the kite fly. I have it on the mid support beam under the foredeck to make sure that the spinaker is kept well away from the jib blocks and this system was fitted when the boat was built.
 
I was wondering if the OP was attaching elastic to the downhaul patch on the spinaker and using this to drop the kite, given the way he was talking about a one string system and it twisting and wrapping up the kite after a couple of uses.
 
It could be that he has set up the 'musketeer' version of the one string system that has a block inside the pole, rather than a more traditional system that has the puller separate.


Posted: 10/12/2016 02:18:02
By: Stuart Bates MR3615
There are some interesting articles on the pump system. This is from the 5oh! Page




Rigging the Pump Spinnaker Halyard


by Peter Alarie
The "pump" spinnaker halyard is an alternative to the 1:4 system that became popular with the advent of bag boats. Both systems allow you to get the chute up faster than pulling it 1:1, but each system has its ups and downs.

Traditional 1:4

Good: Easy to rig and maintain

Chute goes up very fast
Bad: Very hard to pull, especially getting the sail out of the bag

Unforgiving if you do not get it up all the way before the chute fills
You generally have to come off of the windward rail to be able to pull the line hard enough


Pump System 1:2

Good: Easy to pull, even when sail is wet

Halyard can be pulled while sitting on the windward rail
Chute can be pulled up even when full
Bad: More difficult to rig and maintain, due to the shock cord in the system

Chute goes up a little slower
System is finicky until it is perfected, then it is very smooth
The basic plus of the Pump is that the skipper can sit on the rail and still pull up the chute. This is great on reaching sets and allows you to hang in a higher line. The system only requires one hand to pull, so you can drive and pull: crews dig this. While critics will say that the chute goes up slower, there are undeniable advantages to being in the high lane on the set. Also, one look at the ultra-competitive 470 class shows that almost 100% of the top boats are using the pump.

So how do you rig it? The basic concept revolves around the Northfix fitting. This fitting is basically a one way switch that locks up the tail of the halyard when you pull on the handle, allowing you to pull up the sail up 1:2. When you release the handle, or "pump" it for another pull, the shock cord take up pulls the slack out of the halyard through the Northfix. When you pull again, the Northfix locks the tail again.

Our halyard comes down the side of the trunk, goes through a small Harken cleat, bullet block on a pad eye 3" behind the cleat, bullet block floating with a handle (this is what you pull on), and then through the "Northfix" fitting which is about 2" behind the fixed bullet. On our boat, these fittings are all together on a wood block mounted to the floor. You could also figure out how to mount all of this to the CB cap, which might actually make it easier to use. The halyard then runs aft to a fixed, double bullet and then forward to another floating double bullet (which the shock cord is attached to) . Run the halyard through these blocks, making a 4:1 purchase and then dead end the tail somewhere aft. The shock cord take up needs to have a lot of throw and a lot of power. Our system is rigged with about 15-20’ of fat ¼" shock cord, dead ending at the thwart, going to the transom, back to the thwart, and then back to the transom where it ties onto the take up block (double bullet).

handle down towards the cleat, the shock cord system pulls the slack out of the halyard, allowing you to take another pump. Repeat until the sail is up, usually 2 ½ times. It is a little complicated and has taken us awhile to get right, but it has been worth the effort. If you learn from our mistakes, you should be able to get very close on the first try.

Problem areas:

Shock cord tension is critical. Too tight and the sail is hard to pull down, too loose and the halyard does not retract smoothly when you "pump".
Cleat height is also cosmic. It has to be high enough to cleat under load, but low enough so that it does not recleat on the way down.
Don’t skimp on shock cord throw; this is what makes it smooth throughout the range.


Posted: 17/12/2016 08:35:07
By: Gareth Griffiths NHRC

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