The New Beneteau First 34.7
Photo: Sam Bourne
Making the systems on your boat more efficient will make a large difference to your boathandling
and will make you faster around the race course. This series of articles is aimed at
illustrating some areas for attention on a standard production cruiser/racer, using the example
of a new Beneteau 34.7.
Part 2: Backstay and vang
The New Beneteau First 34.7 is an IRC-focused Cruiser-Racer from the drawing board of Farr Yacht
Design. This new offering is a departure from the normal Beneteau formula in that she is
aggressively positioned in IRC and features a deep T-shaped bulb keel with a high ballast ratio.
The standard boat is entirely Harken-equipped but there are some tweaks you can do to make boat
handling easier and get an edge on the competition.
Backstay
The standard boat in this case comes with a good backstay arrangement that is lead to each
side where it can be adjusted by either the mainsheet trimmer or the helmsman. The system has
a series of 2:1 'cascades' which double the power of the system at each one. It starts off
with a #737 Stainless Runner block. This is sized to suit the breaking load of the standing
backstay. The second block is a #6057 75mm ESP block, then dropping down to a #2660 75mm
Carbo block. This gives an 8:1 (2*2*2) cascade before the final 6:1 purchase.
Upper backstay cascades to final purchase
Photo: Sam Bourne |
Neat detailing on the backstay chainplate. Note the elastic to hold the blocks
upright when lines are loose.
Photo: Sam Bourne |
The final purchase uses 29mm Carbo Blocks with a #344 29C Triple at the top and four #340 29C
Single blocks at the base, neatly organised on the chainplate. This gives a total purchase of
48:1, meaning this is an effective and easy to use tuning tool. The final controls are lead to
each side through four # 350 29C Cheek blocks, one at each corner of the transom, and one at
each side of the wheel. The lead then runs up the cockpit side to #150 Cammatic cleats with
# 375 Extreme Angle Fairleads to allow adjustment from any angle.
This allow you to repeat settings, calibrate the backstay by marking at regular intervals along
the first cascade line and referencing this against the position of the triple block.
Vang
Most standard production cruiser/racers do not have sufficient purchase in the vang to make it
an effective, easily adjustable tuning control. This of the times when you are sailing a
little 'pressed' downwind in some breeze and need to ease the vang in a puff. It is locked
solid in the cleat, you cannot release it easily until it is too late and you wipe out.
It is not the fault of the cleat, it is simply a symptom of insufficient purchase in the vang.
On the 34.7, the vang system is composed of a number of 2:1 cascades leading to a 4:1 purchase
and then a single tail to a #240 swivel jammer in the centre of the coachroof. This allows any
of the crew to get to the vang tail to easily adjust it.
Three vang cascades lead to final 4:1 purchase.
Photo: Sam Bourne |
Three vang cascades lead to final 4:1 purchase.
Photo: Sam Bourne |
The Top block is obviously the most loaded block in the system and is a #6057 75mm ESP Teardrop,
leading to a #6065 57mm ESP Teardrop and then a #2600 57 Carbo Single. This gives an 8:1
purchase which is then attached to a 4:1 final purchase using 40C Fiddle Blocks, #2655 & 2656.
This give a 32:1 total purchase giving plenty of power to use this as an effective tuning tool
and, probably more importantly, keeps the load on the cleat low for easy uncleating.
Links:
Part 1: Mainsheet and Traveller
Part 3: Headsail Car Control and Inhauler
Part 4: Spinnaker Systems and Cockpit Layout
