Topic : Single Pole System

Are there any images of alternatives for a single pole system? Im thinking of devising something that does not involve end to ending the pole as I tend to sail with different crews with various levels of experience. (and I dont want twin poles)

Posted: 04/06/2010 11:52:00
By: dv
You could try the Spiro™ launcher:
(first 2 pics - nb the links are broken so no more detail available)

We used one for a single pole on the I14 in the good old bad old days of massive symmetrical spinnakers and it worked OK.

Proctor/Sélden does a similar fitting:


Posted: 04/06/2010 12:11:29
By: Richard
Yes there is an alternative system. If you can get hold of a copy of Mark Chisnel and John Hodgart's book "Dinghy Systems" (ISBN 1-85310-392-6 published 1993) there are pictures of a single pole system on a 505. Unfortunately I believe the book may be out of print so I will attempt to describe the system. The single pole has its uphaul and downhaul permanently attached at the outboard end of the pole. The inboard end of the pole has a ring that slides along a shockcord stowage system just like a Merlin. There is the fairly standard shockcord stowage ramp at an angle of about 30 degrees along the boom, but instead of the shockcord attaching to the front of the mast in the Merlin fashion, it simply carries on in a continuous loop all the way round the front of the mast and back down to the other side of the boom. It is only held up because it passes above the pole eye on the mast. The inboard end of the pole has a standard spinny pole fitting but the outboard end can be a fork if so desired, rather than the standard clip. The idea of the system is that the inboard end of the pole can pass round in front of the mast in order to stow either side of the boom. With the forked outboard end the guy will drop out when not under tension (and hopefully not before!). The comment in the book reads "It works well in 505's but has not caught on in other classes." I have never used such a system but I suppose it wouldn't really cost much to try it.

Posted: 04/06/2010 12:34:05
By: RichardS
Mr Vines, I have a spiro in my shed, bought it after discussing the merits the system with Nick powell who used it on 505's and 3413 when he had it about 15 yrs ago.system seemed to be idiot proof so it'll be fine for you! I'll bring it down on Sunday .

Posted: 04/06/2010 13:31:53
By: PP
There have been many complaints of Spiros causing black eyes on this forum before...

Posted: 04/06/2010 13:58:50
By: Mags
maybe not so idiot proof after all!  still I bet not many 505 crews at 6 ft plus ever for thought.

Posted: 04/06/2010 15:56:34
By: PP
I changed to twin poles having used a single pole system with starboard side stowage. Worked like a twin pole set up, but it has a piston on the outer end. 

Still have the pole if you want it, collection or postage....

Posted: 04/06/2010 17:17:14
By: John B (3404)
David, try taking a look at Chris Pollard's N18, Antedote.  It has a self-launching single pole system.  I sailed the boat with Charlie Morgan and Kaan Yargici at last year's N18 champs at Weymouth and the spinnaker launching system worked well.

Posted: 05/06/2010 16:45:33
By: Richard (3233)
Thanks for all of these. Ill have a look at antedote and try mr P's 'idiot' proof system. If not the non
spiro system looks pretty straight forward. best dv

Posted: 07/06/2010 09:41:58
By: dv
We have been using a twin-pole Spiro for the last 3 months. New to Merlins, and the crew cannot stretch her arm above her head - so the only way of launching a pole is to pull a string.

The spiro goes on the mast in place of the normal D-ring. It may be possible to use pulleys attached to the D-Ring while getting things sorted if you want to experiment.
We use the normal twin-pole outer ends (snodger / down haul, guy through the ring etc).

The inner end of the pole has the string (6mm I believe) attched to the end of the pole. It is led through the spiro, down through the deck to a turning block mounted upside down under the deck, then exit next to the mast through a cam cleat. Pull the string and the pole goes out.
The retrieval is done by releasing the string, and elastic pulls the pole back into position along the boom. The elastic goes from the pole through a pulley at the clew end of the boom, forward inside the boom to a pulley, then back to the clew end again where it connects to the second pole. We have also kept the normal Merlin twin pole elastics connected as guides: to help prevent the pole swinging back in the wrong place.

Advantages / issues etc:
- You rub away at the side of the mast with the launch rope: duck tape is not strong enough, you need some mylar protection here.
- The distance from deck to hoop (where the crew fits) is quite short: so it takes 5 or 6 pulls to launch the 6ft+ pole, rather than 1 or 2 pulls that the RS400 could use.
- The crew can launch the pole while balanced against the hoop: a good stable platform and helps issues of standing on the centreboard case and weight forwards at the wrong time.
- The gybe is simple: uncleat, gybe boom, pull new launch rope. No need to worry about going forward and nose diving or balancing just after the gybe etc.
- BUT sometimes the pole gets locked into place on the spiro and un-jambing the rope is not enough: you need to knock / pull the pole to release it.
- A tight elastic is great for retrieval of the pole, but if it is too tight it makes launching the last 6 inches very hard work: especially when at this point you are often pulling the kite out of the chute as well. Pulling the windward corner back to the shrouds before launching is essential.
- If you can't quite get the pole on (the helm has forgotten to release the snodgers!), then you can sail quite happily, with the kite setting correctly, with the pole 2 inches short of the fitting. With the usual clip on pole, it must be on the D-ring or its no good.

After about 2 months of sailing, we find we cannot gybe onto a close reach as quickly or as tightly as a normal pole operated by someone with 1-2 year experience. Would we be expected to?
Hoisting and gybing on the runs seems to be just as quick.

Happy to share experiences...

Posted: 07/06/2010 14:38:04
By: ChrisJ
Our boat (3666 - Enchanted Evening) is at Brightlingsea: Happy to show people, and to steal anyone elses ideas for improvements!

Posted: 07/06/2010 14:40:13
By: ChrisJ
Pictures, to make it easier to see, are here:

Posted: 07/06/2010 15:33:27
By: ChrisJ
thanks chris

Posted: 07/06/2010 16:42:09
By: dv
Even easier

Posted: 07/06/2010 17:17:49
By: Garry R
Errrmm - I can't make this link work for me. It just opens up my Windows Live Account. I must be doing something wrong but don't know what. Help please?????

Posted: 07/06/2010 18:57:17
By: Dimwit
Just realised that happens for me too!!  But at least you get to know a bit faster!!

Posted: 07/06/2010 20:31:17
By: Garry R
Does this link go straight there?

(and if you can tell me what special characters you are adding to make it a link, that would help!)

Posted: 08/06/2010 09:49:46
By: ChrisJ
You just use the box marked "link" below the box where you write your main message.

Posted: 08/06/2010 09:56:27
By: Mags
Nah... it must be harder than that! :-)

Posted: 08/06/2010 11:05:00
By: ChrisJ
Yep - that link works perfectly. Thanks

Posted: 08/06/2010 11:47:10
By: Dimwit
Chris - just ensure that with the pole out your set-up is not overlength. I am not sure that the reduction in length from the removal of one of the pole end is not enough to offset the added length of the Spiro. I am sure that you have trimmed off the relevant inch ...

Posted: 08/06/2010 18:51:17
By: Andy Hay - 3626 Business as Usual
That was something I reminded P&B to check when they were setting it up...

Posted: 08/06/2010 21:17:10
By: ChrisJ
DV if you collect a few twigs , some bits of tape, some cotton string and a couple of nails you should be able to build a pole system up to your normal standard.......

Posted: 10/06/2010 10:35:26
By: WP


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