Tuesday, March 7, 2017

Outdated Aluminum Spars Break


broken spars pile up in Laser clubs
Sydney recently experienced one of its frequent weather events an east coast low pressure system, throwing 20 gusting 30 knots at the harbour.  Of the 20 Lasers that ventured out that day on Middle Harbour, two were towed home with broken bottom sections.

This is typical for club sailors. Spars become unreliable after about three years depending on use.  The elite sailors replace their spars, indeed their boats every year which club sailors cannot afford to.

The problem has been exacerbated by the modern approach to Laser racing in strong winds.  The story goes that on his way to the top, Tom Slingsby obtained funding for a stack of sails and decided to test their limits by super tensioning the cunningham and vang in strong winds. It worked well, the boat became more manageable and the technique became standard practice.




typical corrosion at a stress point



Unfortunately the 1970's designed aluminium sections are not up to the task and with the increased stresses they break.  Only recently has a carbon top section been introduced but the class is still stuck with outdated aluminium bottom sections and booms.

Metal fatigue is not the only problem.  Laser spars corrode, especially in salt water.  There are two kinds of metal are in contact with the aluminium in the form of the rivets and the fittings.  New bottom sections and booms start to show signs of bimetallic corrosion within months of purchase with tell tale corrosion grooves fanning out from stress points.

The super vang approach is also tough on other fittings which are now not reliable either.  Vang tangs break as does the bolt holding the goose neck.

The Laser class seems unable to adapt to these problems. It is not only a cost issue, it puts extra responsibility on club race management and makes the boat unsafe in strong winds.



4 comments:

  1. I was one of those Lasers. My bottom section (full rig) snapped off at the vang fitting! I have a 3 year old boat and suffered quite a few breakages this season. This and also hearing the news of the state of the idiots running Laser Performance has brought me to this site... It is also great to see how my favourite sailing partner is going? - Raptor

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  2. Great to hear from you Raptor, you probably recognised the pile of broken spars. The new B2 is going well, just need a few more Aeros on the harbour. Planning to have three out on Tuesday, a new mid week group starting to form. We have a face book page 'RS Aero Sydney', thanks for following. And as you can see I have fired up the old blog.

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  3. Hopefully you get back into Tillerman's top 3!

    I am watching the state of Laser affairs closely. I think with the current Laser mess, the Aero has every chance to taking off. It is also a well made, true one design boat compared to the sloppy build of the Laser! - Raptor

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  4. The Tillerman has been extended an opportunity via FB (RS Aero Class) to sail my Aero on Sydney Harbour. He can't make it this year, maybe next.

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