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Does anyone know where i may be able to access a plan or drawing of the universal joint used in the Twistleyard Rig?
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Re Almost.........
Joe, the rig was designed by Hugh Barkla back in the 60's and is currently in production with Ratsey and Lapthorne sailmakers.
There was an article in one of the yachting mags some months ago which showed this rig in operation.
The blurb from R&L does NOT give you close up detail of the universal joint at the heart of the system which I understand comprises a spring which absorbs the loads.
However, I have designed my own system which is yet untried and is wonderful in its simplicity. The secret of the rig is to allow and absorb the forces inherent in the sails without transferring these pressures back to the mast and thus through the boat.
Email me if you would like some further details.
Joe, the rig was designed by Hugh Barkla back in the 60's and is currently in production with Ratsey and Lapthorne sailmakers.
There was an article in one of the yachting mags some months ago which showed this rig in operation.
The blurb from R&L does NOT give you close up detail of the universal joint at the heart of the system which I understand comprises a spring which absorbs the loads.
However, I have designed my own system which is yet untried and is wonderful in its simplicity. The secret of the rig is to allow and absorb the forces inherent in the sails without transferring these pressures back to the mast and thus through the boat.
Email me if you would like some further details.
G
Guest
Guest
Re: Re Almost.........
Errrr .... couple of questions.
a) What's a Twistleyard Rig please? and
b) My understanding of a sailing boat is wind hits sail - wind creates pressure on windward side and vacuum on lee side of sail - differential pressure x area = force - force is transferred to boat via mast and rigging - boat moves through water. If the "the force inherent in the sails" is "absorbed" without "transfering these pressures back to the mast and thus through the boat" what makes the boat move through the water?
Best regards }}
(
Ian D
Errrr .... couple of questions.
a) What's a Twistleyard Rig please? and
b) My understanding of a sailing boat is wind hits sail - wind creates pressure on windward side and vacuum on lee side of sail - differential pressure x area = force - force is transferred to boat via mast and rigging - boat moves through water. If the "the force inherent in the sails" is "absorbed" without "transfering these pressures back to the mast and thus through the boat" what makes the boat move through the water?
Best regards }}
(Ian D
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Re: Re Almost.........
Ian, its a downwind rig for the Trades.
Its simply two yankees or two gennys of similar size which are either stitched together on the luff or run together on a single double grooved forestay.
Both sails are poled out with whisker poles but instead of the poles being fixed to the mast on the inboard ends, these ends are joined together. This join is then suspended from an uphaul and pulled forward towards the forestay with a second line and pulled aft to the mast by a third line.
At the heart of the whisker pole joint is a strong flexible universal spring or equivalent which absorbs loads which would be otherwise transferred via the poles, to the mast.
Apparently it removes much of the roll from downwind sailing and can be simply furled by pulling on the furling line.
Ian, its a downwind rig for the Trades.
Its simply two yankees or two gennys of similar size which are either stitched together on the luff or run together on a single double grooved forestay.
Both sails are poled out with whisker poles but instead of the poles being fixed to the mast on the inboard ends, these ends are joined together. This join is then suspended from an uphaul and pulled forward towards the forestay with a second line and pulled aft to the mast by a third line.
At the heart of the whisker pole joint is a strong flexible universal spring or equivalent which absorbs loads which would be otherwise transferred via the poles, to the mast.
Apparently it removes much of the roll from downwind sailing and can be simply furled by pulling on the furling line.
G
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Re: Re Almost.........
Aaaaah I can relate to that and can even see how it could reduce rolling.
With the centre joint of the whisker poles being sprung the foot of the sails would effectively be moving semi-independently of the mast. Lateral thrust would be dissipated and transferred into fore and aft thrust on a "push-pull" basis.
Damn clever these Twistleyards - I wonder if they are related to the Oswaltwistles of Lancashire?
Aaaaah I can relate to that and can even see how it could reduce rolling.
With the centre joint of the whisker poles being sprung the foot of the sails would effectively be moving semi-independently of the mast. Lateral thrust would be dissipated and transferred into fore and aft thrust on a "push-pull" basis.
Damn clever these Twistleyards - I wonder if they are related to the Oswaltwistles of Lancashire?
G
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Guest
Re: Re Almost.........
"Sailing Today" ran an article on this rig in February 1998 if you want to explore it further.
"Sailing Today" ran an article on this rig in February 1998 if you want to explore it further.
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Guest
There is a "TwistleYard Marine" in Dunbar, - he can provide poles and the "hinge". There are "CopyShop" articles available. It works well but can take time, effort and patience to get all hoisted - so not really for short passages. Total sail area in "twins" should not be too great - e.g. if genoa c.300 sq.ft. then twins of c.170 sq.ft. each about right - hoisting sails on hanks means they can be dropped quickly on inner forestay - also used as working jib and occasionally one twin folded onto the other....Not sure about the single luff / twin groove foil combination - poles need to be 5-8% longer than than perpindicular from luff to leech.
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