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Outhaul design for 470?

TakK

New Member
Hi 470ers

Can you give me some advice on making the outhaul on my 470 a bit more useful? BTW, this is the same boat as the one in the jury-rigged 470 thread where LaLi has helped me a lot to sort things out.

At the moment, I've just tied the outhaul with a knot because the plastic cleat doesn't bite well.
470_outhaul.jpg

I haven't been able to find much info about the outhaul for a 470 apart from the links below.
470 Boom - AG+ Spars
FORUM - Timonieri.it - La più grande Community di vela in Italia - Circuito base randa

The class rules seems pretty open about outhauls so I guess anything goes as long as there's an outhaul?

I've made a couple of sketches of my ideas. What do you think about these and what would you advise?
470_outhaul_concept_sketch.jpg

Sketch 2 (bottom):
This 2:1 outhaul just replaces the plastic cleat with a Clamcleat. It's at the end of the boom so not much scope of adjusting it while underway but maybe it's good enough? Is a 2:1 purchase enough on a 470 for recreational use? If not...

Sketch 1 (top):
I based this 4:1 system on the old pre-XD outhaul hack for the Laser (except we're using multiple lines and blocks). It has a block running along the mast and a Clamcleat with a becket. I was tempted with a system where you pull aft along the boom but I guess you'll just end up pulling the boom out of the gooseneck? In this sketch, I've placed the Clamcleat half way between the main sheet and kicker attachments so that you can reach it even when the boom's out. Presumably this position means that the crew has to adjust the outhaul? Where would you place the Clamcleat? How much movement of the clew should I allow for? I also wanted to put the additional weight near the mast end so that the boom stays out in light winds.

Although sketch 1 is based on the pre-XD Laser outhaul, I'm a bit weary of it because I really didn't get on with the old Laser system. I could route the outhaul down to the deck (like the Laser XD arrangement) but that adds to the cost (more blocks) and complications (too many ropes on the deck) so something like sketch 1 might be good enough for my purpose?

The 470 is mainly for taking the kids out for sailing and the occasional club race so it doesn't have to be super duper.
 

LaLi

Well-Known Member
TakK, you've already put as much thought into the system than just about anybody ever :confused: :D The outhaul is one of the less important adjustments on a sloop rig, and even during a race you don't use necessarily more than two settings - shelf foot "on" or "off" for upwind/downwind. For purely recreational purposes, almost anything adjustable is fine.

The class rules actually do prohibit leading the outhaul anywhere else than the boom. The traditional system has been like the AG+ diagram shows, with a Clamcleat and a lead block (so that you can pull in all directions) on the bottom side at the front end. (That picture is not to scale, the block is usually all the way forward and the cleat some 10 to 15 cm back.)

The system in the Timonieri diagram (originally from the GER 71 site) is needlessly complicated, but you can see how most of it runs inside the boom. That in itself is standard, but not necessary by any means.

The range of adjustment (the distance that the clew moves) is somewhere between 5 and 10 cm, and 2:1 is enough.

_
 

TakK

New Member
Thanks LaLi

The outhaul is one of the less important adjustments on a sloop rig, and even during a race you don't use necessarily more than two settings - shelf foot "on" or "off" for upwind/downwind. For purely recreational purposes, almost anything adjustable is fine.
That's good news. I won't get too worked up about it and go for something easy then :) .

The traditional system has been like the AG+ diagram shows, with a Clamcleat and a lead block (so that you can pull in all directions) on the bottom side at the front end. (That picture is not to scale, the block is usually all the way forward and the cleat some 10 to 15 cm back.)
I understand that diagram better now; in the AG+ system, the outhaul Clamcleat is fore of the vang. That's probably a good place to put the Clamcleat then.

BTW, that GER 71 site is a gem. It's got all the pictures I was after.
 

LaLi

Well-Known Member
that GER 71 site is a gem. It's got all the pictures I was after.
The diagrams are nice and clear, but I rarely link to it because the outhaul system isn't the only one there that can be characterized as "needlessly complicated". Skeptical of the functioning of some of those, too.

_
 

David Hughes

New Member
A single cleat under the boom aft of the Vang attachment Works well. 8-to-1 is best (this is 4-to-1 internally and 2-to-1 at the clew).
 
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