sailmakers were made by sticking together several layers with a thermoplastic adhesive. This glue was either applied in between the fibres or added on top as a separate layer. Next, the layers were bonded by pressing them lightly together in a vacuum bag that exerted a maximum pressure of around 1kg/cm2
and then cured for a few
minutes. ‘The glue fused around the fibres and solidified again once cold,’ he says. ‘Unfortunately the bond was reversible under certain conditions.' With the wrong sort of temperature fluctuations it could be weakened and ultimately come unstuck. Small pockets of air trapped inside the laminate were another cause of failure. By contrast, the manufacturing process developed by Banks uses specially formulated two-part soft resin that bonds with an irreversible chemical reaction to create a new molecule out of the original two. The layers are laminated in a vacuum and heated evenly to an optimum temperature by a line of infra-red lamps. After that they are squeezed between six-metre long (full table width) rollers and a glass surface at an extreme pressure of 12 kg/cm2
,
(10 to 15 higher pressure than simple vacuum lamination) which Semeraro says is the only way to incorporate Dyneema filaments into the laminate and also eliminates even tiny air pockets. ‘Waves of heat and over-pressure proceed uniformly over the whole vacuumed piece of sailcloth,’ he explains. ‘Once the cloth is stabilized, after one to three weeks of vacuum at a controlled temperature, the curves are drawn. This solves the great problem of how to very precisely reproduce a given design, which is common with moulded sails.’
The other crucial difference is at the end of the process, when finished sails are post-cured in a vacuum for days or in some cases
After six years of producing sails using this method with no
delamination problems the results speak for themselves. Paolo
Semeraro’s ‘secret’ recipe involves a custom two part soft resin that forms an irreversible chemical bond – he says it’s the only way to fix slippery Dyneema fibres into sailcloth
even weeks in a dedicated ‘rest room’ where both temperature and humidity are precisely controlled. The time factor does add to the cost – and big projects must be
commissioned months in advance – but Banks’ sails are still competitively priced and far from the most expensive.
The structural skin of these sails is another unique selling point, which Semeraro says gives them a longer service life. Rather than just adding a simple taffeta on a simple mylar film, as a UV-protective outer layer, Banks Sails uses a combination of very thin polyester film and lightweight (1/3 of a taffeta) non-woven polyester cloth pre-impregnated with a UV-resistant resin. The result is a strengthened, toughened sail that not only stands up to being clouted repeatedly against shrouds and spreaders but also absorbs the compression loads that are inevitable when sailing in choppy seas, rather than allowing the motion of the boat to distort the shape of the sail.
When structural skin is combined with Dyneema load-bearing fibres, Semeraro is so confident about his sails’ shockproof, rip-stop properties that he says it’s almost impossible to cut them with a sharp knife. ‘With a one-metre rip in the middle of a Code 0 you can continue to use it normally
without causing any further damage, even in strong winds,’ he adds. And that alone is an enormous benefit if you’re setting off on a long-distance ocean race with just one suit of sails. ‘We come from a pure racing background,’ Semeraro says. ‘Our sails were used by the X-35 and ORCi World Champions every year from 2008 to 2012 and we’ve also made sails for several Maxi Rolex winners. More recently we’ve focused on performance cruising and offshore racing sails, where durability is just as important as performance. ‘Banks Sails Europe might not be the most fashionable brand but we have a very solid customer base in performance cruising and offshore racing, which proves the longevity and performance of our products. ‘Our clients include owners of very successful boats like the XP-44 Xp-Act which has been on the podium of the Middle Sea Race for eight consecutive years and the Grand Soleil 58 Leaps & Bounds which despite her cruising configuration has been on the podium of the Med’s main offshore races in 2018 and 2019. Our most recent projects include sails for boats like the Solaris 68, 64, 50 and 37, Grand Soleil 80 Custom, other Grand Soleil yachts from 58ft to 39ft and some interesting custom projects.’
www.bankssails.it
q SEAHORSE 69
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68 |
Page 69 |
Page 70 |
Page 71 |
Page 72 |
Page 73 |
Page 74 |
Page 75 |
Page 76 |
Page 77 |
Page 78 |
Page 79 |
Page 80 |
Page 81 |
Page 82 |
Page 83 |
Page 84 |
Page 85 |
Page 86 |
Page 87 |
Page 88 |
Page 89 |
Page 90 |
Page 91 |
Page 92 |
Page 93 |
Page 94 |
Page 95 |
Page 96 |
Page 97 |
Page 98 |
Page 99 |
Page 100 |
Page 101 |
Page 102 |
Page 103 |
Page 104 |
Page 105 |
Page 106 |
Page 107 |
Page 108 |
Page 109 |
Page 110 |
Page 111 |
Page 112 |
Page 113 |
Page 114 |
Page 115 |
Page 116 |
Page 117 |
Page 118 |
Page 119 |
Page 120 |
Page 121 |
Page 122
