New one string method

27/07/2013 17:37:55
Miles
Experimenting yet again.

New one string raking rig and rig tensioning system. Literally one control line across thwart. Move it to starboard: mast rakes back and vice versa, lowers kicker puller all linked in. Less blocks, less string, less weight. Less money.

Testing in progress.

http://www.littlejoesolutions.co.uk/merlin/merlinrocketonestring3646.jpg
28/07/2013 14:16:40
Mags
I like it - hope you can prove it works. The current systems boggle the mind...

Does the one line require cleating?

28/07/2013 16:15:55
Miles
Hi Mags

Theoretically I don't think I do need cleats because all the initial forces are balanced. It's the induced or dynamic loading which might result in a temporary imbalance.

So initial thought was yes, I ought to have cleats just in case. So came up with opposing clamcleats either end of 'thwart' (link to photo). Easily released and re-cleated from either side of boat.

Having said that, it seems pretty stable with just rig tension holding it in place.

Testing continues.

http://www.littlejoesolutions.co.uk/merlin/onstringcontrol.jpg
29/07/2013 12:25:53
Andrew M
Didn't Jacko work out and fit an arrangement very much like this for Lounge Lizard (3484)?  IIRC it still had it when Rob Heath first had the boat but there were problems with it and he abandoned it for the more conventional stringing system.

29/07/2013 13:45:48
Simon Hipkin
I currently have the Jacko-built 'Steppenwolf' sitting in my workshop and it does indeed have an almost identical lever system. I know that Keith C spoke to him about it a few months ago and the general feeling was that the Winder system was far superior.

29/07/2013 16:53:55
Miles
I met with with Keith C last month when he was over, and ran the idea of levers past him. The main question was would it work, we couldn't see why not. He did mention that someone had some years ago tried a lever system.

What I ended up with is not quite what he and I had been discussing, I had two levers in that and rig tension under the foredeck (more complicated).

If it has already been tried by Jacko then fair enough, though it would be interesting to see how alike these systems are. Have we two identical solutions?

Simon, Have you got a photo of this Steppenwolf system or any idea what the problems were?

29/07/2013 17:34:08
Simon Hipkin
Hi Miles. If you email Keith, he's got some photos of the Steppenwolf lever on his computer. It does appear to be very similar to what you are currently trying. The general feedback was that it did work although it was felt to be inferior to the Winder system therefore the idea was dropped. Inferior in what respect I do not know. Keith will be able to tell you more. The travel certainly appears limited on Steppenwolf, and in reality it is still quite complex. I was initially going to go down this route as well on my new boat, but decided against it. The 'conventional' one string system is a thing of great beauty when set up correctly.

29/07/2013 21:11:29
Chris M
I think the lever ran into problems with the amount of travel it had - or rather didn't - have. 

If you can overcome that it should be on a par with the standard system.

30/07/2013 08:05:32
Dave F
The system on Steppenwolf was put in by me when the boat was built in 1994, It had all the travel required, It was altered after I sold the boat, The mast went forwards with one string, and back to the controlled stop when the main was centered at the start of the beat. 
It move jib, shrouds & lowers, because the kicker was attached to the bottom of the deck stepped mast it didn't need to move.

Dave.

30/07/2013 09:41:16
Miles
I can get a fair amount of travel on this (at least the same as the all string system I tried) a different lever can obviously increase that.

What is the target/magic figure for travel?

Dave, did the jib tack move or stay fixed? I have it fixed.

30/07/2013 11:32:48
Nigel
We had the lever system from new on 3484 then later refined with Jacko on 3551 with an early Selden carbon rig. Shrouds and lowers connected in with separate control for rig tension. The idea was to have something almost automatic, as the pressure on the spinnaker would 'pull' the rig upright downwind, then at the leeward mark use mainsheet tension/kicker to rake back 'automatically'. There was an adjustment under the deck next to the mast, to pre-set how far back to rake and another on the starboard side that would allow the crew to pull the rig upright if going lighter upwind. Both deck stepped and the kicker was attached conventionally. 

All worked really well with plenty of travel and excellent for keeping head of the boat on mark roundings. Crikey, even had a titanium lever!

There was a lot of 'stuff' under the foredeck, so everything had to be shrouded to protect the spinnaker. It was easier to set up on 3551 as we could easily remove the mylar/kevlar foredeck to work on the system.

Might have some pictures somewhere.

Good luck!

30/07/2013 13:14:42
Dave F
jib haliard had a 2-1 pully to get the ratios correct. with the mylar deck, it was very easy to service, and worked very well.

30/07/2013 23:51:48
Jules 3518
I developed the Jackson 'no string' system further on my Lawrie Smart NSM1, Substitute, when I deck stopped it.  Ever mindful of a bargain, I  wanted to deck step as cheaply as possible, so used the old strut lever as the raking rig lever. The fixed end was not actually fixed, but free floating and had the rig tensioning purchase attached to it. The lever floated between two vertical posts which formed the mast support from hog to deck.  The forestay came straight through the step (very fiddly when rigging) and hooked onto the lever  the shrouds came up from turning blocks on either side of the hog and were also attached to the lever.  lots of careful calculation to work out the ratios of distance from pivot point to ensure that when the rig raked the relative tensions in forestay and shroud remined the same. When you applied the rig tension between the lever end and a fixed point under the mast step, it pulled up on the shrouds applying tension to them, and at the same time applied tension down on the forestay.  There were two simple cleated purchases on the lever to limit travel and I used these to set the rake limits dependant on wind strength and then just left them untouched while sailing, unless conditions changed dramatically.
Theoretically, once the tension was applied and the limits of travel set, the rig would sort itself out. Off wind it just pivoted forward as the wind pushed the mast forward. Up wind, it pivoted backwards through application of kicker and main sheet tension - hence 'no string'. Rig tension remained constant. In reality, I found there was too much friction, and had to let off rig tension when turning off wind, so it became a 'one string' system.
Smoked Salmon came as a shock when I bought her. Very conventional. Not sure what happened to 'Substitute', but I have a suspicion that the floating rig tension lever would have been changed for something more straightforward. Perfomance wise, the deck stepping was definitely a step forward, but it was me that let the boat down, not the revolutionary rig control system...

31/07/2013 09:43:06
Miles
Hi Jules

Mines along similar thought lines, attach shrouds and halyard ets. directly to the lever.

What I'm trying, which I think is different from yours and 'Steppenwolf', (thanks for the photos Keith) is that I'm hoisting the jib on its own forestay [which can come back down in the luff] it this forestay that is attached to the lever. Rig tension is applied via the 'old' jib halyard a lot easier to tension.

31/07/2013 09:44:59
Miles
typos Mine's  and etc. not ets.

31/07/2013 12:27:24
Dave F
You need to make sure the jib tack stays as low to the deck as possible, no air must escape between the ib and the deck.
on Steppen, the jib loop came out in the normal place, so I could see the rake.
The rake went from -4 inches to + 30 inches, on a run with the mast at -4 the boat was very quick.
I also used an old mast ram leaver
dave.

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