Reefing sails?

[Torchy]

Developments in the 18s have got me thinking again about reefing mains on Cherubs.

Many 18s now have the ability to put a reef into the small rig for 20kn+ conditions. It's more than the reduction in sail area, in fact it might be just as much about flattening the main even more and reducing the height of the centre of effort.

Quite a challenge for the sail designers.

Is anyone thinking along these lines? Clive has made some very pertinent comments about getting the boats we ask for ie currently a real handful in 20kn

[roland_trim]

Is this more "rules" based than speed?
From the pictures googled, that does not look like a cheap lashed reefing point or something you'd shake out between back to back races. I'm sure one of the 18'ers will be along shortly to confirm how long/how many sails they are restricted to in a season and hopefully some better pictures.

Maybe the question is more are we as a group of owners/rule setters thinking about limiting rags? This would .certainly drive some people to think of zips, bundles, ties etc. whilst currently there is a trend for a cut down (often a "recycled" sail).

[deefender1098]

my understanding is the 18s do this mostly to lower the centre of effort, from the races i have seen there has been little difference in raw pace and the racing is much similar to as a few knots less wind and everyone is on full size small rigs, lowering the centre of effort and reduced roach make a significant change to making the boat easier to control, especially in the windward mark bear away and down speed gybe drops, not something that cherubs struggle with the same as 18s i think i am right in saying that most modern boats flip the t-foil's angle of attack and point the nose down (generally) without problem and the spinnaker chutes rather than bags means dropping the kite is a much less risky zone in cherub sailing, still an interesting idea

[Torchy]

Best place to see them is the latest race on 18footerstv

Agree with Defender...it's a lot about the bear away in an 18 but they did not appear to pay a penalty in upwind speed. Not sure about downwind.

For us in Cherubs I think many feel they need a smaller main in high wind speeds and the ability to roll and zip up some of the foot and(?) flatten the main might produce a faster sail than a cut down main.

[JimC]

I built a rig on my PlusPlus with a zip reef in the foot of the main and the mast telescoping down into the mast stump. It worked well enough as far as rigging was concerned, and you could put the slab in or take it out in a very few mins with the boat tied up to a pontoon - I even did it once without taking the main down although that would be foolish in breeze. However for some reason I never seemed to be able to get the boat in the groove upwind with the shortened rig. Of course this was a single sail rig. Having a jib in the mix would make it a lot more complicated.

Slab in...

Note there's a set of points higher up for a really big chop down for nightmare conditions, but that didn't involve stumping the mast any further.

Slab out...


The bearings and supports for the mast telescoping were a right pain in the neck to build because mast track had to disappear down the stump.


Something I've noticed in the past is that there are windy years and quiet years, windy decades and quiet decades. I haven't tried cross referencing this to trends in class rule changes!

[MikeBz]

Pardon me for unlurking....   The 18s are allowed 2 rigs, i.e. 2xmasts, 2xjibs, 2xmains, 2xkites.  Over the last decade their #1 rigs have grown hugely. Although they have always been limited by a max height  the true mainsail and jib jib areas have grown a lot.  In turn the #2 rigs have also grown so as to keep a sensible step between the 2 rigs. This has got to the point where the #2 rigs are close to the size of the #1 rigs of say 25 years ago.  So now they are struggling to get the #2 rigs around the course in 25 knots.  A related development is that the masts have got stiffer to support the big square-top (or even gaff style in some cases) mainsails.  With a very stiff mast it becomes viable to reef the main as there are less issues with the luff curve, so they are now starting to regress to a reefing point on the #2 mainsail to lower the centre of effort.  As has been pointed out, if your rules don't limit the number of sails (or number you can use in 1 event) then the only reason for adding a reefing point would be to keep the cost down.

[roland_trim]

Pardon me for unlurking....   

Completely welcome. Other views are always good.

[Torchy]

Hi Mike,

Don't apologise for unlurking...glad to have your input.

Cherub '2nd rigs' are about the size of 90s Cherub rigs (but 90s boats had a single wire) and 'full rigs' become a real handful somewhere between 20-25kn. I think many Cherubs have a 'full rig' which is below the allowable maximum of 15.5sqm. Some people have cut down old mains for 20kn+ which occasionally show up at events but these haven't been seen to give a clear edge in the sense of swinging any results that I know of.

Not sure exactly where the rules take us...I think there is a perception that someone using multiple rigs '...to gain advantage...' might make themselves unpopular and get voted down following a nationals in which this advantage showed. The main argument is cost.

I suspect a well cut reefing Cherub mainsail might confer an advantage come that 'windy year' and enable 15.5sqm rigs on boats sailed by lighter crews in more moderate conditions but developing the 'cut' would be the issue. You might get neither one thing nor the other ie a slower sail in moderate winds and no advantage come the heavy stuff.

I can think of 2 or perhaps 3 crews who are competitive up to 14kn or so who feel they can't keep up once it gets more windy.

Cherub masts have pretty fixed bend...certainly I never see Loco's uppers loosening and they have no adjustment.

Watching what happens in the 18s will be interesting.

btw on the question of design I suspect the use of a zip is counterproductive. I think Velcro might be better enabling a 'footline' analogous to a leechline to be used. This might enable more control of the shape in conjunction with the outhaul.

[Ben Howett]

I have a really hard time buying into the cost argument against having 2 sets of sails.

The upfront cost is clearly higher but total cost of ownership does not increase - unless you are one of those people still clinging onto 10 year old rags and wondering why you cant go upwind anymore. Most people with small sails have recut older sails at limited cost, and those buying purpose built second mains are likely to be those who would be buying new sails to stay competitive anyway.

The combined usable life of 2 sets of sails cut for their purpose will be greater than simply replacing your 'main' set a few years down the line.

[Tim Noyce]

"Cherub masts have pretty fixed bend...certainly I never see Loco's uppers loosening and they have no adjustment."

In my experience, the leeward upper becomes pretty slack upwind in anything more than about 15 knots. As you wang on enough cunningham to ignite the mast tip then it will almost always go slack to the point of waving about when you are applying sufficient mainsheet tension. Letting the kicker and cunni off at the windward mark before the bear away will load the uppers back on again to control the mast tip with the added kite loads.

[Clive Everest]

I too think that it is a false economy trying to put reefing points in.
The reefing system will also cost.

We have a small main that we use about 10-15% of the time (QM and Weston this year).
I suspect that using it on those days has halved the degradation of the big main.

Because the racing is not close on small main days you can tolerate a sail that is knacked or other wise compromised by having being adapted from something else. The Peter's old RS200 main did the job and was effectively free.

The issue of people not using full size rigs is potential a thorny one.

A number of sails have been measured significantly smaller than the sail makers software suggests they should be. Including ours. I have more confidence in the sail makers software than our measurement process.

It is the intention of our rules to accurately measure main and jib areas.
I believe that there are boats with full size rigs that have been measured small and boats with rigs that have measured close to full size that are probably over sized.

[Torchy]

Loco's main rig is under 15.5sqm. I measured it in compliance with the ISAF measurement handbook using triangulation and extrapolating rounded corners as directed. As I recall it was about 14.5sqm. I would have to do it with help to be sure exactly how far under it is.

I don't see how the reefing system will add significantly to the cost of a new sail.

I am (as previously) more persuaded by the 'having a second main saves you money on the bigger mainsail' argument. However, as I recall Matt Kiddle, when measurement officer, felt that someone could potentially protest against someone who used multiple sails within a series to 'gain advantage'...and why else would one do it?

As I recall the previous discussion ended inconclusively.

Were I to order a new suit of sails or start a new build I'm not sure what I would do.

btw Tim - Loco must have a particularly stiff rig

[Ben Howett]

btw Tim - Loco must have a particularly stiff rig

...or perhaps you just dont have a Noyce to apply your cunningham?

[Tim Noyce]

For the record, the measured areas I have on file for your Fyfe sails Nigel is 15.05 square metres.

[Clive Everest]

I don't think that the discussion was inconclusive.

The consensus was that most active boats now had second sails and that these had not added significantly to the costs but did allow people to keep racing in conditions where they otherwise would not and that there was therefore no need to change the rule that currently has no restrictions on the number of sails.

It was however felt that we should keep the kite measurement rule even though it is problematic as we do not want people building monster light air kites.