MERLIN ROCKET FORUM

Topic : New sails on an old boat

I have a Merlin 'Summer Wine', 3239 which I started sailing at the end of last season and a little over the winter ... I'm tempted to try some more modern sails on it, as the set with it are not too bad, the main seems to be of 1984 vintage, so I suspect something a little more modern might work a little better.

The jib supplied with the boat has too long a luff anyway, even with the hook all the way down into the magic box, the mast is raked back a long way and very little tension on the shrouds ... and at 2.6m is a bit smaller than its original 3.1m jib .. so playing with a more modern set wont do it any harm.

Theres a "flatter" cut suit of P&B in the for sale section, which the guys at P&B think will work OK on the stiffer old mast, so that should be OK,

I was wondering about the jib sheeting angles ... are the modern jibs cut for a tighter sheeting angle? if so .. what would people suggest as "standard" distance from the centreline to run the sheets to? My current set up has a turning block somewhere down near the kicking strap as the sheeting point ... (at least, I think its supposed to be the sheeting point :)

Any advice welcome ...


Posted: 11/01/2010 00:29:48
By: Robin Szemeti
I think it is the distance between centreline and the jib block which you are thinking of. Very old Merlins had the jib lead to the sidedeck, whereas modern ones have the block right inside on the floor.


Posted: 11/01/2010 11:09:32
By: Mags
If all of the shackles connecting the jib to the tack point and to the wire jib halyard have been reduced to be as short as possible, perhaps you could take the jib hayard along to a chandlers and have them shorten it by 200mm or so. Sounds like you have no range of rake adjustment at all - just fully raked all the time.


Posted: 11/01/2010 12:20:05
By: KM
@mags Yep, that should be OK then, the jib leads are well inside, on the floor down by the kicking straps, so I guess those will be OK.

@KM, I think I'll try the new jib and get a new halyard suitable for whatever length they are on the new sail plan. At the moment the mast sits well back, I can only just get tension with the shroud levers on their 2nd to tightest setting and the boom hangs very low over the hoop, even with minimal kicker applied. I presume the boom should hang approximately horizontal, with the mast in its "upright" position? I'm not sure if the odd boom angle is purely due to the the mast rake or the leech might have stretched over the years?


Posted: 11/01/2010 13:03:11
By: Robin Szemeti
I would look through the bits on the forum about tuning / setting up a mast for the first time - calibrating the positions of rake, may involve shortening your shrouds by pin adjusters off the levers, but somehow you need a downwind setting with the mast close to true vertical, a light/normal seting with around 150mm of rake, and progressively more rake till the mast wont go further or the boom hits the hoop, or it has about 400mm of rake (see tuning gides) Make sure the levers can apply tension through the range. It needs to do that with a new or old sail on. I don't think you can fiddle the mast rake to compensate for a soft leech on the main.

I think treat the mast rake position separately from the boom for a start - don't confuse the issue with the boom angle and saggy main. It might be that the newer jib you get will have a more 'standard' wire length and avoid major setting it up each subsequent jib change. If your main is that worn out it just means you can't rake as far without banging the hoop but with a good sail on the rig should ideally be capable of a decent range even with the kicker hard on.

For the jib fairleads, i'd expect them to be around the overlap between 2nd and 3rd plank.

Sorry i'm rambling!

Are there any 'merlins' who could help where you sail?


Posted: 11/01/2010 15:03:16
By: KM
Aye, sounds all like sensible advice ..

I think the jib fairleads are somewhere around the 2nd/3rd plank .. might be 3rd/4th .. but certainly not out on the sides.

And yes, I *do* need to set that mast up ... and I when this current freezing spell is over, I shall be out there with my tape measures and spirit levels.

On a related note ... can anyone suggest a good repairer in the Midlands (I'm in Kidderminster, so the left had side of the midlands would be useful) .. there are a couple of gluing jobs that need doing and its way too cold for epoxy to go off in any sensible amount of time and I probably don't have enough clamps anyway .. I tried Severn Boats down in Worcester, but hes moved to smaller premises and he can't fit the Merlin through the door :( suggestions welcome


Posted: 11/01/2010 18:23:35
By: Robin Szemeti
You could try John Howard - Boat Builder and Albacore sailor in Tewkesbury.  He deck stepped and modified MR 1700 a few years ago and his wood work is STUNNING! Send me an e-mail number for his mobile number. But here are his details off Yell.com:
John Howard Boat Builders & Repairs
Tel: 01684 773371 Unit 4, Croft Farm, Bredons Hardwick, Tewkesbury, Gloucestershire GL20 7EE


Posted: 11/01/2010 19:36:57
By: Russ Hopkins
Morning Robin,

When you talk of replacing sails, not completely sure if you are thinking brand spanky, or new second hand.

Many owners of older boats have spent hours trying to get the geometry of rake, sheet angle etc sorted with second hand sails, often ending up with a bodge of shackles and string, with only a moderately good result...

If in doubt I would advocate a visit to a sailmaker who can assess what is needed and produce a jib with the right dimensions, and more importantly, the right cut for the sheeting angle. A flat cut jib sheeted wider than design will not be effective. Even if you use a second hand main, a new jib to the right shape will be well worth the investment.

GGGGGGGG


Posted: 12/01/2010 08:03:18
By: Measurement Man
hi G,

This will be a "new secondhand" set, as stated in the original post, there is a "flatter" cut suit of P&B available in the for-sale section and the guys at P&B are of the opinion they will work fine with the older, stiffer mast. If things work out OK, I might even run to a deck stepped rig next year ..who knows.

As for the sheeting angle .. I don't think thats going to be a problem, as my boat is already sheeted in the modern way and the idea is to bring the rig up to date, so ultimately, if the sheeting points need moving, they will be moved. The boat was originally set up with a 3.1m jib, somewhere in its live it got swapped to a 2.6m jib with too long a luff, so its not right as it stands.

You are correct though, I *could* just order a "made to measure" set for the existing rig, but one of the things that attracts me to the Merlin is the experimental nature of the class. Messing about with it is half the fun :)

What I wont have is a mess of fittings and a badly calibrated rig. The idea is to improve and perfect, not make worse. I'm an engineer by training and if its not right, I don't sleep easily in my bed :) I've already sorted out a number of minor problems on the boat, messing with the sails is the next logical step :)


Posted: 12/01/2010 09:43:16
By: Robin Szemeti
Hi

I still have a good as new set of P&Bs on the list. used for only one Nats in 2008 and ready to go (mian kite absolutely mint). They got us to the front a couple of times but the boat sadly had small failures and we slipped back to 12th overall that year. Open to offers.

Barnsie


Posted: 12/01/2010 09:46:44
By: barnsie
Robin,

I've fitted s s/h suit of Alverbanks to our NSM2. The jib luff wire was a different length from the previous one (temporary fix with a shackle - I'm planning on swapping the luff wires as the jib luff is sewn in a big seam and the head and tack held by control line).

I found that I needed lots of tension on the shrouds (and luff) - this causes the mast to bend - otherwise the mainsail luff doesn't match the mast (non)bend and the top batten will not tack.

I guess that your Summer Wine is the "high bow tank" style - without the bulkhead - and this means that the rig tension you can usefully apply is much less (the hull flexes - so you can't apply lots of rig tension). With that arrangement, you may well need to have sails cut to match the rig as you won't have the range of rig tension to adjust the rig to the sail....

Our old Smokers had a similar problem

HTH

Colin (3387)


Posted: 12/01/2010 11:02:27
By: Colin
Well, im hoping that the "flatter" cut of the sails im getting will work OK on the stiffer mast ... I know the "full" cut of the standard modern sails can be a problem, as you found, with stiffer masts, so hopefully, this flatter set should work OK with the stiffer mast, P&B seem to think they should. 

Personally, I'm going to leave the luff wire as-is and make up a new halyard to suit, giving the correct mast rake.

3239 has a low bow tank and a fairly substantial bulkhead, so its pretty stiff, if it was the old style high-tank design, then yes, I agree, they tend to just fold up like a clamshell from what I can tell, but this looks pretty stiff and seems to take a fair bit of rig tension without much flexing,

I'm hoping it will work ... at the end of the day, if it doesn't I can just put the sails on eBay :)


Posted: 12/01/2010 12:14:43
By: Robin Szemeti
Rbin,

Thanks for the update - I wasn't sure how much rig tension you could apply.
The Alvabank main (mylar) is fine - one I wind up enough tension to bend the mast. Ours is fitted with a pulley system for the shroud adjusters (from the stem head - multiple purchases turning block through the bulkhead) - that manages the tensioning. I did have to change the top batten though.
Oh, yes, the new main is also loose footed - but that's not a problem.

HTH

Colin


Posted: 12/01/2010 12:42:46
By: Colin
Yep, we have the traditional quadrant gear levers for the shroud tension, which seem to be quite an easy system.

Our current main is loose footed, but I suspect its original sail was whatever the opposite of loose-footed is :), as the boom has a luff groove. The boom will be too short for the new sailplan of course, (2295mm as opposed to 2503mm) but it needs replacing anyway as I ripped the outhaul car out of the luff groove on its last outing ... it seems sometime in its past, the outhaul car which normally has 6 little nylon wheels runing on 3 pins in the luff groove ... lost one or two wheels .. well, 6 actually. and 2 pins. It had been sliding on a single bare pin in the luff groove, wearing its way through the aluminium, until I hauled on some kicker and it ripped clean through .. :( for now, a bit of dyneema rope around the boom is doing the duty, but long term, it needs a new boom really, so ight as well get a longer one to fit the new main.


Posted: 12/01/2010 12:50:35
By: Robin Szemeti
Hi again,

I've an old boom in the garage - from the Smokers Satisfaction.

I'll measure it - if it's any use (it's well used!) let me know - I'm sure we can arrange transport/collection (We're near the M4)

Colin


Posted: 13/01/2010 12:49:33
By: Colin
Most kind ... I'm up near Worcester, but I get down that way occasionally.

I guess it needs to be long enough to leave a little room for the outhaul .. say 2.6m? Failing that I could always buy a nice new carbon one :)


Posted: 14/01/2010 00:25:22
By: Robin Szemeti
Dear Robin,

The boom I have is 2290 mm long (overall - for a 2280 mm foot) - looks like it's a bit too short for you.

Sorry,
Colin


Posted: 24/01/2010 13:35:48
By: Colin
Thanks for measuring Colin, 

As it happens, I jut picked up a carbon boom that was offered on here that will suit the new sails.

Thanks again for checking.


Posted: 24/01/2010 22:03:25
By: Robin Szemeti

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