Composite Top Section – Myth busting and what you need to know
This post was published in May 2017
The introduction of the long awaited composite top section was probably not one of ILCA’s finest moments with a lack of availability meaning that although class legal they weren’t allowed at events as people simply couldn’t buy them. The first event to allow them was the Delta Lloyd regatta which has just taken place in Holland. The following article, written for Southeast Sailboats by Team GBR sailor Michael Beckett should provide you with everything you need to know about the new composite section.
Starting with a fundamental – bodyweight?
I’ll put myself on the line by saying you do not need to gain or lose weight. If you were a bit light for the Laser rig you were sailing, you’re still a bit light. Ultimately, the only modification to a Laser that would result in the ideal weight changing is an increase or decrease in sail area.
Money and where to buy?
The composite mast supplied by Laser Performance is priced at £412.50. Australian sections shipped over have been selling for up to 700 Euros, however both composites are made in the same factory in New Zealand. The only difference between the two is the mast collar and end plugs, the British made ones being slightly narrower in diameter – an issue which can easily be overcome by packing tape – try to avoid using electrical tape as this ‘squashes’ easily reducing the benefit of packing the masts. The only consideration you should have when purchasing a mast is to allow plenty of time ordering them from Laser due to continued availability problems.
What are the quantifiable differences?
The old aluminium sections had what can only be described as a gaping chasm in design tolerances with masts weighing anywhere in between 2.6kg and 3.1kg. The new composite masts weigh between 2.4kg and 2.55kg. It is worth at this point noting that the weight of a carbon section isn’t a perfect determinant of stiffness. Also in aluminium sections the weight does not correlate that well with stiffness, one aluminium section that is heavier than another is simply more likely to be stiffer. If you need more information as to why, read up on second moment of area theory then the answer should become apparent.
The new composite mast is also longer…yes you read that right. The new masts are about 6mm to 8mm longer than an aluminium one. This means that your downhaul, vang and leech are all under more tension than previously.
Theoretically, a composite top section should not get bent. If, after a big day on the water you look down your assembled mast and it looks bent then keep squinting until you are sure the bend isn’t in either the bottom section or from the mast collars not being packed properly. If you are still convinced your carbon mast is bent then structurally something must be wrong with it, such as the carbon fibres being broken; your mast is subsequently defunct.
The final difference is that the composite section is a few millimetres narrower in diameter, which should make it easier to ram your burgee in the top of the sail.
What are the unquantifiable differences?
Unquantifiable differences are a fancy way of describing feel. The composite section does not, in my opinion and I would welcome you to disagree, feel that different to an aluminium section. I would
say it feels like using a new, straight aluminium section. During big light wind roll tacks the boat is less inclined to heel over, this is due to having half a kilo less weight at a point about 4m (for a standard, less for radial & 4.7) above the deck. This missing weight makes negligible difference when you’re sailing the boat upright!
Any changes to set-up?
The old aluminium sections had a big helpful red arrow stuck on the bottom of the mast telling you which way the mast should be pointing at the join with the bottom section. The composite sections do not give you any indication which way it should be rotated, which is quite a frustrating omission by the manufacturers. Having done some research, the best idea would be to have the two rivets on the mast collar on the port and starboard sides of the mast, as opposed to fore and aft. The reason for this is that if a solid monel rivet is compressed by carbon (as it would be if the rivets were facing fore and aft) it will cause the carbon to delaminate sooner. Composite Laser masts haven’t been around long enough to validate this theory, so only time will tell.
Looking after your composite top section
Finally a few notes on the care of what is, by Laser standards, quite a big investment. Where possible keep the mast out of excessive sunlight as this will accelerate the delamination. We’ve all been rigging up at some point to hear a painfully loud clang as the aluminium mast rolls off the deck, this is best to be avoided with your new composite section. Carbon does not take impact so well and there is potential for the fibres to start snapping sooner.
The reality of the new composite section is that there isn’t a huge difference, the difference of changing from a MkI to a MkII sail is greater. Regardless of what material the top section you’re sailing with is made of, a boat that is on a small lift or in a small amount more pressure will be faster, which ultimately is what the Laser is all about. There are some appreciable differences, and as always by being aware of these you can get more out of your Laser sailing and know that you’re being smart with how you maintain and sail your boat.
Written by Team GBR Laser sailor Michael Becket for Southeast Sailboats. Southeast Sailboats supply customised control line systems, mainsheets, blocks and the CarbonParts compass for the Laser including our unique 8:1 downhaul system . Please note that Southeast Sailboats do NOT sell the composite top section!