MERLIN ROCKET FORUM

Topic : Genni at the boat show

Thank you Jon and Richard for having the time and patience to explain your spinnaker pole launching system, (at least four times, not counting the pulling of strings to see what went where), the new rudder stock and canting rig.
The pole launching looks fascinating, no need for the crew to stand up, the clew of the spinnaker held tight to the spinnaker pole, brilliant!


Posted: 05/03/2012 09:55:15
By: fribbs
Sorry, should be Genii!  And I looked it uo to ensure I spelt it properly!


Posted: 05/03/2012 09:56:45
By: fribbs
Jon showed me over Shebazzle's bits on Sunday, and I was yet again reminded of the hours and hours of ingenious thought that Jon had put into his creation. This is what Merlin Rocketry is all about. The spi pole system is really effective, and can be retro-fitted quite easily, and without the need to shell out £350 on a twin spinno device.


Posted: 05/03/2012 10:22:11
By: Keith Callaghan
I also loved the dinghy show and was hugely impressed with the highly infectious enthusiasm displayed by both Jon and Richard. That spinnaker pole system looks REALLY good. No puller to fight with or forget either!! Unfortunately I arrived when Richard was halfway through explaining it to someone and I didn't have the heart to ask him to repeat everything. Both Jon and Richard seemed very keen that people should feel able to retro-fit the system to their own boats. I wonder if someone could be persuaded to write up a description of what ropes went where. It actually looked pretty simple (just some "outside the box" thinking) but I would hate to miss some obscure but essential detail if I tried to do it myself.


Posted: 05/03/2012 12:16:39
By: Richard Saunderson
BAU will be sporting some Genii style mods this season, including new transom (thanks Mr Insurance Man - cannot recommend Bluefin highly enough), pole launch / puller combo (linked into the one-string), carbon integrated rudder fittings (I have the prototype rudder stock) and low aft buoyancy tank. Also going for split aft bridle main with twin tiller extensions, just for fun. You'll all be pleased to note that there are no bilge keel (Rule change anyone?) or hull modifications this year!!

Rock on.

Of course the other thing to note is that JT's woodwork is amazing. The new gunwales that he fitted on BAU are something else. At least that's my excuse all sorted for this season - I am just protecting the furniture!


Posted: 05/03/2012 15:04:04
By: Andy Hay - Business as Usual
I have been asked for pics of the "musketeer" (all for one) pole launcher. Lots of people were snapping away, including most of the journos, so I am sure we will see them in various articles soon. Andy Rice also shot some video that will be on his Sailjuice site (www.sailjuice.com).  If anyone has any other pics please feel free to post them here!


Posted: 05/03/2012 15:26:06
By: Richard Parslow
...or you could just take your boat to JT and ask him to fit it for you.


Posted: 05/03/2012 15:29:04
By: Richard Parslow
That was my "boat of the show" just for the pole system but add the neat tank and the canting rig and nothing else came near it for innovation.
I'll be studying the pix too and retro fitting when we eventually get 3434 on the water again. It could become the "fitting of the year" that everyone goes for in 2012


Posted: 05/03/2012 20:40:21
By: Pat2121
Can anyone point me in the direction of some pics? Couldn't make the show :( 
Cheers
Ben


Posted: 05/03/2012 22:01:11
By: BenR
Definitely my stand of the show. I have got to thank Richard and JT for explaining no end of questions that i have long wanted answers to such as the pros and cons of jib overlap and trim tab centreboards...and why rake and rig cant works...and how spreaders are set up...i could go on. Sincere thanks to Richard and JT. Chris


Posted: 05/03/2012 22:40:59
By: Chris Martin....another one..
Richard, I took quite a lot of photos of Shebazzle's pole launch system. I haven't had time to post them anywhere on the web yet, so I'll email them to you, and to anyone else who wants them.


Posted: 06/03/2012 21:27:35
By: Keith Callaghan
Keith - I wonder if it might be an idea to email the photos to Mags so he can put them on the Merlin website? I believe his email address should be in the committee section of the site.


Posted: 06/03/2012 23:07:57
By: Richard Saunderson
Richard S - will do. I have now posted a functional diagram of Jon's & Richard's system on my website. See below. If there are any mistakes or omissions, please let me know ASAP.

http://www.bluelightning.co.uk/Merlins/SHABAZZLE%20spi%20pole%20system%202012.pdf

Posted: 07/03/2012 11:07:13
By: Keith Callaghan
Great diagram Keith!  

I think that the plastic hip joint is an adapted Seldon Spiro Pole End Knuckle


Posted: 07/03/2012 11:33:42
By: fribbs
I've had some camera-phone pics from Martin Hughes, which I will post later today unless Keith/anyone sends me some better images.


Posted: 07/03/2012 12:37:38
By: Mags
Keith - thanks very much for the diagram, it's very helpful. I'm just puzzled by a couple of things.
1) - According to the flyer available at the stand on Saturday, the musketeer launch "obviates the need for both a puller and the hated snodger". Does Jon and Richard's system have a pole downhaul that is adjustable or have they gone for a "fit and forget" downhaul?
2) - On your diagram you have shown the pole launch rope going forward to a sheave through the foredeck which you describe as "sheave on centreline,
>700mm from mast". It's the "on centreline" which puzzles me. I thought that the through-deck sheave was offset out to the gunwale about 1/3 of the way back along the foredeck. Was I looking at the wrong thing?


Posted: 07/03/2012 13:11:51
By: Richard Saunderson
Just to confirm, we are talking of twin poles here, and they presumably have uphauls at the outer (far or forward) end?


Posted: 07/03/2012 13:13:17
By: ..
Keith - you're a star for that diagram. Only question is how many times the shock cord goes back and forth along the boom - I thought it was a continuous piece for both sides.
The through deck sheave was definitely off centre as there was one each side.


Posted: 07/03/2012 13:15:02
By: Pat2121
A continuous piece of return elastic makes the best sense as you're never going to want to deploy both poles at once. It also tightens up the retention of the inactive pole whilst one pole is deployed. Was that elastic INSIDE the boom? It looks to be mounted ON TOP of the boom in Keith's diagram. It would be preferable to me to have it on top - I just wondered whether there were any PRACTICAL downsides to an external mount.


Posted: 07/03/2012 13:28:17
By: Richard Saunderson
My system:
The elastic goes into the boom very easily around a couple of deck sheaves at the rear end.
Inside the boom the elastic is continuous around a pulley at the front end. That pulley is adjustable in length from the mast end of the boom.
Getting the tension correct is critical! Too tight, and the crew cant launch the pole and it flies back at horrendous speed. To loose and it hangs down below the boom to catch the helms head and doesnt retrieve all the way. Adjusting the length (and thickness / stretchyness) of the elastic is important: hence the pulley inside the boom is on an adjustable (just tie it off) distance from the boom end.


Posted: 07/03/2012 13:41:27
By: Chris J
Oh dear, I thought that my diagram might raise a few questions that I could not answer.
1. I can answer the one about the deck sheaves. Richard, you are right - Shabazzle had the sheaves offset each side, but Jon told me that his present setup makes this unnecessary, and they would be better placed on the centreline, where they are more effective doing the job of the puller.
2. The shock cord: It was definitely external to the boom on Shabazzle. It may have been one piece rather than 2, but I did not check that. Chris's system is possibly neater, as it's internal, and easily adjustable.
3. Jon T just phoned me to say that the socks (on the boom end to take the poles) are really necessary if the helmsman is to avoid injury from flying poles. I omitted these from my diagram, but the photos give you an idea. Incidentally, I've sent the photos to Mags so hopefully he will post them on this website.


Posted: 07/03/2012 13:57:00
By: Keith Callaghan
Fribbs, you are right - Jon confirms that the hip joint is a Spiro bit. As it's Spiro it's probably expensive.  I think I might be able to source an alternative at a reasonable price. Watch this space.
As for the doing away with the need for an adjustable downhaul, I think the theory is that with the 'old' system the snodger needed to be adjustable mainly to facilitate the gybing procedure, i.e, the thing had to be let off to be able to push the new pole forward and on to the ring, then pulled on again. With the Musketeer system this is unnecessary, as you just have to pull hard on the launch rope to get the pole on the mast - much easier than pushing over your head from a very awkward stance. I guess that the downhaul is still adjustable but adjustment will not be needed during a gybe.


Posted: 07/03/2012 14:19:18
By: Keith Callaghan
Avoid those flying poles. 3 possible approaches:
- Ours: we have left the normal end of pole guide elastics in place. So the retrieval elastic pulls the pole back, while the guides keep the pole end near the boom and above the helms head.
- Black Boat: A very neat small ring around the pole, that the pole slides through, which is attached on short elastic to the lowers. This helps to prevent many different nasty swings of the pole at the wrong time.
- Genii: which uses a sleeve on the end of the boom to catch the pole (and to catch in the wind on the beat and cause drag?).


Posted: 07/03/2012 15:03:26
By: Chris J
Chris - I believe that in the second option you describe from the black boat, the small ring on the elastic attached to the lowers is to help pull the knuckle out of the Spiro fitting when retracting the pole. The Spiro fitting seems to have a tendency to keep hold of the knuckle which prevents retraction. On your own system which retains the elastic "ramp" which we currently use, have you experienced the dreaded "pole-end-in-the-eye" scenario that JT has avoided with his tubes?


Posted: 07/03/2012 15:57:19
By: Richard Saunderson
PHOTOS! Thanks Keith.

http://www.merlinrocket.co.uk/gallery/default.asp?folder=gallery/building_and_repairs/genii_design_2012

Posted: 07/03/2012 18:38:53
By: Mags
RE:>> On your own system which retains the elastic "ramp", have you experienced the dreaded "pole-end-in-the-eye" scenario?
Avoided, in that my (and my crew's) eyes are still bruise free (system in use for 2 years now) - Yes.
But things do get quite close at times! Although, the boom gets quite close to my head as well - so close doesnt necessarily mean its close enough to hit!
Dropping in a breeze (when helm tends to be balancing on the deck more) is much safer. Dropping in light winds is when things get closer.


Posted: 07/03/2012 21:39:41
By: Chris J
RE:>>the small ring on the elastic attached to the lowers is to help pull the knuckle out of the Spiro fitting when retracting the pole.
YES. And its needed! The pressures on the pole tend to make it "stick" into place, and having something to knock it out is very useful.


Posted: 07/03/2012 21:48:14
By: Chris J
Thanks Keith for posting the diagram and photos of yet another LSD* from JT bringing deep joy to all Merlin sailors.

Yes, we have a separate uphaul/downhaul fixed at the outboard end of the poles, adjustable via cleats on the king post. We set the pole height according to windstrength and forget about it.

Keith is right when he says that the through-deck sheave(s) for the launch lines could be on the centreline.

The retractor elastic is one piece that goes twice the length of the boom, so it can pull quite hard without reaching its elastic limit. The pull from the elastic is insignificant when you use a launch line (unlike when you have to rig the pole manually), so you can make the elastic fairly tight for rapid pole retraction.

We don't think there is much drag from our 'socks' on the boom: the back end is open and they never flap! There is probably more drag from a loose spray top...

*Labour-saving device. What did you think I meant?


Posted: 07/03/2012 22:35:35
By: Richard Parslow
Richard - Thanks for your continued commentary on this system. Since I am about to cut into my beautiful wooden decks and don't want to make the wrong decision, I wonder if you could throw some light on the pros and cons of putting the through-deck sheaves either on the centreline or out at the gunwale?


Posted: 07/03/2012 23:00:20
By: Richard Saunderson
Now we have a new "one string" that deals with both pole launch, snodger and puller all in one. I suggest we make it pull on the jib barber-hauler too!


Posted: 07/03/2012 23:09:53
By: Mags
One of the problems Dave and Jonny had with their launcher last year was that with the boom off the centre line the natural path of the pole is out to windward rather than towards the forestay.  Has the Musketeer or other variants solved this issue?


Posted: 08/03/2012 14:46:17
By: Tim Fells
A bead on the guy keeping the snodger forwards makes a huge difference. It keeps the ring which runs on the guy within 2 or 3 feet of the clew on the kite. We were using a simple self launching pole on Armed Forces at the nationals, not having a proper spiro fitting, we found that the guy knots were never in the right place, but we intend to persevere with it.


Posted: 08/03/2012 15:41:35
By: Chris I
Richard - JT fitted two of the old style Proctor metal mast sheave thingies on the centreline on our beautiful wood decks on BAU. Basically, a double deck sheave when the puller would normally go.

JT also has a 1:2 pully running inside the poles so that there is plenty of spare tie-on string between the kite clew and the pole when the kite is stowed - there is no ring on the guy on this system and the clew always goes to the pole end.

Guess what I am playing with this weekend!!!


Posted: 08/03/2012 20:42:24
By: Andy Hay - Business as Usual
Thanks for that Andy. That would seem to make the through-deck sheaves closer to the mast than on Shabazzle (and less than the 700mm on the drawings)but if it's good enough for JT and good enough for BAU it's good enough for me! It also means less damage to the foredeck. So - I'll just go and sharpen those chisels. Any feedback you can give after playing this weekend would be MOST welcome Andy! Thanks again.


Posted: 08/03/2012 21:26:12
By: Richard Saunderson
I noted that the sleeves on the end of the boom were held open with a continuous piece of fine elastic from the top outer forward point of the sleeve , along and up around the mast, above the pole eye and back to the other sleeve. 
Having capsized once because the loose spinnaker pole end dropped down the helm's buoyancy aid as he ducked and carried him overboard as we gybed, those sleeves look like a great answer. We have pieces of plastic drainpipe on the Lark but they are bulkier.


Posted: 09/03/2012 06:15:30
By: Pat2121
There's nothing new in the world.

One Sunday afternoon in the 1950s a non-sailing engineer was a guest at Minima Y. C. Having watched the Merlins, Nat.12s and Cadets racing he asked why we didn't lean our masts into the wind or at least sail with our boats heeled to windward. I recall that Brian Appleton, one of Minima's top Merlin sailors, disagreed which led to an interesting argument.


Posted: 09/03/2012 08:07:50
By: Robert Harris
Tim, you will see from my drawing that the Musketeer system has the line from the end of the pole permanently secured to the spi clew, not terminating in a ring which slides on the guy and is thus free to go anywhere. Thus when the pole is launched the pole end will always end up at the spinnaker clew.
Richard, I put ">700mm" as the distance from mast to foredeck sheave boxes because the further forward they are, the more is the 'puller' effect. They could of course be nearer the mast, but further is better.


Posted: 09/03/2012 11:38:08
By: Keith Callaghan
OK, probably the most important question - how do you step the mast / drop the jib without the puller?


Posted: 09/03/2012 13:51:09
By: Tim Fells
Presumably you tie the spinacker halyard to the bow area.


Posted: 09/03/2012 15:10:03
By: Mark
The puller hole on the mast is still there. Would be easy to have an extra line for that purpose, which can be left with the cover when racing...


Posted: 11/03/2012 22:10:23
By: ChrisJ
See here for more details... http://www.yachtsandyachting.com/news/161996/50th-Anniversary-Hamble-Warming-Pan

http://www.yachtsandyachting.com/news/161996/50th-Anniversary-Hamble-Warming-Pan

Posted: 12/03/2012 14:06:54
By: Chris J
I forgot I had been sent these photos of the Winder at the boat show. Doubtless there are some little differences to the pole system used on Shabazzle....but which are crucial? And who is right?!!!

http://www.merlinrocket.co.uk/gallery/default.asp?folder=gallery/building_and_repairs/new_winder_2012

Posted: 24/03/2012 21:26:07
By: Mags
@Mags
Frankly I am amazed you even asked that last question.


Posted: 27/03/2012 18:16:41
By: Richard Parslow

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