Graduate dinghy new mainsail
by Dave Talboys 21 Feb 2008 07:35 GMT
As with every organization we are continually looking to see if improvements can be made to our Association and following the 2007 National Championships it was suggested that modifications could possibly be made to our mainsail to improve the dinghies handling and to make it more responsive and enjoyable to sail without moving away from the original Class design and format.
The reigning 2007 Graduate Dinghy National Championship helm Stephen Cockerill of Rooster Sailing Ltd offered to examine the possibilities and see if indeed improvement could be effected and to produce a prototype for testing with the following design brief:
- To use the same spars and black band measurements.
- To move the centre of effort back a little to stop the need for forward raking
centerboards. (Hence the bigger top)
- To make the rig no more hard work upwind - and possibly more manageable in
power terms (hence a two stage depowering with two different length top battens)
- To make the sail look more sexy - so the class have something to shout about at
the next Dinghy Sailing Show (hence a sexy looking tri radial design).
- To help invigorate the class as a whole.
This was done and the prototype was tested and found to produce all aspects of the
design brief and more.
The new sail will fit the standard mast and boom. With a boat in a reasonable state of
tuning, in the first instance at least, the mast rake and step position remain unchanged.
The reason is that the original sails and rig were taken directly from the N12 and the
shrouds and forestay positioned as on the N12 as well. As the Grad evolved the
mainsail was cut down, jib enlarged and the forestay moved forward. This moved the
centre of gyration forward and it has always been difficult to balance the boat even after
pivoting the centreboard as far forward possible.
With the new mainsail the centre of gyration is moved aft leaving the boat better
balanced.
With the new sail the boat goes rather well and you will have to position helm and crew
a little differently and sit out more. On the water the overall impression is a stiffer more
secure ride.
Response to changes in wind strength and acceleration out of a change in tack, is much
better.
The tendency for the boat to heel and steer into wind and the sail to stall in strong winds
when close-hauled is absent. Down wind, the boat picks up and accelerates in those
short gusts that previously passed the boat by. As the sail now powers the boat
properly, the bow digs in less and after the gust the slow down more progressive so that
the stern does not sink into the water so fast. For sure, helm and crew will have to move
about to keep optimum balance but without that frantic style of the past.
The overall effect is much more comfortable and rewarding with less effort needed to get
the best out of the boat. And yes the boat surfs and planes earlier too. It is a shame we
did not have this bigger sail years ago. Now we have and we believe it turns a good boat
into an excellent one. The new sail is important for more than just better performance
and handling, for sure, it does both of those things making Grad sailing much more
pleasurable. It also gives the boat a much more purposeful appearance and very
modern profile that hopefully draws attention.
Details of the new sail measurements can be found on the Graduate Dinghy Association Web Site.