New Radial cut Standard Sail in the works? New composite top mast?

Discussion in 'Laser Talk' started by JuanCH, Sep 22, 2011.

  1. Sailorchick

    Sailorchick Member

    Likes Received:
    5
    Trophy Points:
    18
    Jeffers, I can't keep a top section straight for more than a days sailing at the moment! Bottom sections (radial) are not much better, I seem to get a few months out of them tops before they bend.
    The top sections I've had recently just seem really weak. It doesn't have to be particularly windy for them to bend. At the moment I straighten my mast (I have 2 top sections at present, one has been end for ended, one hasn't yet) before every sail and its bent after every sail.
     
  2. jonathan_twite

    jonathan_twite Member

    Likes Received:
    3
    Trophy Points:
    8
    So what's so special about a radially cut sail? If I read the articles correctly, they imply that they have been aiming for identical sailing characteristics. Is it just for longevity? As for carbon masts - from what I have seen, they have a tendency to shatter when they hit the bottom (when violently turtling) or capsizing onto the shore, both of which are a hazard when sailing on a river.

    The carbon mast just seems to be another money grabber, sailing a laser is becoming an expensive hobby for club sailors (I just bought a competitive but older National 12 for less than a new laser sail).
     
  3. jeffers

    jeffers Active Member

    Likes Received:
    31
    Trophy Points:
    28
    If there are issues like this with the current new spars then LP/ILCA need to get involved or perhaps this is the builder being a little sly as they will want a carbon spar for the extra cash it will being in for them.

    Perhaps I am being a little cynical! The top section on my boat is possibly the original that came with it, or it may have been replaced. It is at least 7 years old to my knowledge.

    I also has a new boat some years back (early 180,000). I did not have a problem with bendy spars on that boat so something must have changed somewhere.

    Also as I sail the 8.1 the higher kicker loads when using this rig makes it more prone to a permanent bend but this has not happened since I end for ended earlier this year.

    To answer Jonathan (and this is just what i have heard/found out). The new sail design is 'supposed' to perform in an identical way in therms of potential speed (i.e. no faster than the current sail) but is hopefully more robust (heavier cloth will help) so the money we spend on the new sails will hopefully) give us a sail that stays in good condition for a couple of seasons. This is their answer to the replica/training sail issue. As long as the price is right this should help!
     
  4. AlanD

    AlanD Former ISAF Laser Measurer

    Likes Received:
    47
    Trophy Points:
    28
    When and if the carbon top section becomes available, it will come with its own problems, which maybe quite different to the aluminium sections. Time will tell exactly what they are, but an example might be that they progressively lose their stiffness over time like carbon bicycle frames. If this is the case, you might find competitors replacing their top sections just as frequently with the additional cost that they can't make them into new booms to replace corroded boom sections. Also remember, that the carbon top sections have only been approved by the class membership to use with the radial sail and not the 4.7 or standard rig, although that just becomes a voting issue at some stage in the future.

    As I said earlier, the new sail release from my understanding is somewhat tied current dispute with the builders and the rights holders and at this stage it's probably too late to release because of the closeness of Olympics. Why this dispute impacts on the release of the new sails will become known to all in the fullness of time and I'm not at liberty to discuss (so don't ask!).
     
  5. AlanD

    AlanD Former ISAF Laser Measurer

    Likes Received:
    47
    Trophy Points:
    28
    Australia has significant problems with radial bottom sections bending (less so since we started importing European sections), but typically most top sections don't bend during their life times unless it's a bad batch. It seems the north America / Europe has problems with top sections but less so the radial bottom sections. Whilst the spares are within tolerance it's a case that some are at the top end of the tolerance and others at the bottom end. It could be a case that those tolerances need to be re-specified or tightened, so that no-one world world wide has issues.

    The critical specification of the section is the cross sectional thickness (controlled by the die that forms the tube) and the extent of the T6 heat treatment (i.e. whether it's maximized for the particular aluminium alloy). The heat treatment will impact on the load required to permanently bend the section (yield point) and the cross sectional thickness on the stiffness of the section within the elastic region and how close it gets to the yield point.

    In 26 years of sailing lasers, I've yet to bend or break a top section, except once when involved in a pre-race collision where two rigs hit each other. However I've sheared off at the deck about 6 standard rig bottom sections and snapped one boom. I've also significantly bent a standard rig bottom when the heat treatment on a particularly batch was completely wrong.
     
  6. harpo

    harpo Member

    Likes Received:
    1
    Trophy Points:
    8
    For a long time I thought Radial bottom sections were *supposed* to be bent because every one I saw in San Francisco was bent. They bend easily out here.
     
  7. TonyB

    TonyB Member

    Likes Received:
    0
    Trophy Points:
    16
    I don't know Alan, I've bent and/or broken plenty of Australian top sections in my time. Any section I've ever had has developed a bend the first time I've put on a solid amount of vang. Not a huge bend, but enough to be visible. This is a pretty common story around these parts.

    Using a top section that has done a fair amount of sailing (say 12 months or more of regular use) is just asking for trouble. It's a skill picking the right time to end for end - I seem to always wait a day too long.

    I don't think the composite section can come quickly enough. Note that it's not a carbon section, just will have some carbon in it - that should make it a lot more durable than straight carbon.
     
  8. oztayls

    oztayls Member

    Likes Received:
    8
    Trophy Points:
    18
    There are some advantages of a composite top mast section and a new radial cut sail that are not necessarily performance related.
    • We don't know the weight of the experimental composite top section, but if it is lighter, the righting moment will be increased. My guess though is they will be trying to make it the same weight as the aluminium section, so there will be no righting moment advantage.
    • The radial cut standard sail will hold it's shape better and it can be depowered more as well. Hans Foch (sp?) talked about this when he designed the current Radial sail, which was based on his Flying Dutchman sail at the time. The radial cut is more versatile in a wider range of conditions, so it makes sense to go that route with the standard sail. It could well be quite a bit faster upwind than the current standard sail too, as is evidenced by the Radial's superior upwind performance against the standard in some conditions.
    • Now let's surmise for a moment that the new top section is made from carbon fibre and it is lighter than the alu section. Then you combine it with a new radial cut sail that is more versatile across the range of wind strengths. What is fallout from that scenario? One answer I can think of is that the standard rig becomes more attractive to lighter sailors due to a combination of increased righting moment and the ability to depower more. We could see a migration of sailors on the Radial and Standard weight range cusps moving from Radial to Standard rigs.
     
  9. AlanD

    AlanD Former ISAF Laser Measurer

    Likes Received:
    47
    Trophy Points:
    28
    I didn't say they didn't bend, just that it seems less of a problem, at least from my observations.

    Washing the collar area well and having a firm but not tight fit will help prolong the life of a top section. Banging it into place or apart really loads that collar rivet badly and leads to the section cracking sooner IMO.
     
  10. AlanD

    AlanD Former ISAF Laser Measurer

    Likes Received:
    47
    Trophy Points:
    28
    Again, the radial cut standard sail has been cut so that it's performance matches the existing the standard sail, as they don't want to make the current sail obsolete. Secondly, the carbon top section is intended for use with the radial rig and not the standard rig.
     
  11. harpo

    harpo Member

    Likes Received:
    1
    Trophy Points:
    8
    I saw one at a regatta last weekend, and was told it's the same weight and has the same bending characteristics (I have no idea how those are measured but I assume the people making them do) as the current aluminum top section.

    Does it perform exactly the same across every wind range, every sea state, every ambient temperature? I doubt it. But will the variations be more than the current variations between different builders in different parts of the world?

    I believe my driving and my tactics lose more races than a millimeter of bend in my mast. So I welcome any change that makes the boat long-term less likely to break ... because I'll sail it more and maybe the driving and tactics will get fixed. :)
     
  12. oztayls

    oztayls Member

    Likes Received:
    8
    Trophy Points:
    18
    I do have reservations that this is possible Alan, given that a radial cut sail will be more stable and hold its designed shape better. I'm certain the cross cuts will be immediately obsolete. However, in the long term, Laser sailors will be better off. The sails have been changed in the past, and the class didn't suffer too much for long.

    Also, a radial cut sail is more expensive to manufacture because there is more wastage. This is the reason that the smaller Radial sail costs about the same as the standard cross cut sail (here in Oz, exactly the same price). To help the class over this initial hurdle, I believe new sail prices will need to be cut to encourage sailors to upgrade and shorten the period of obsolescence. In any case, the trade-off will be a longer lasting radial cut sail, especially as the cloth is heavier also.
     
  13. AlanD

    AlanD Former ISAF Laser Measurer

    Likes Received:
    47
    Trophy Points:
    28
    Manufacturing costs are an extremely small part of the overall retail cost of the sail. The cost is in the distribution network. Hopefully the cost associated with the new sail will be fairly similar to the current costs. A lot of work has been done specifically to make sure that the current sail doesn't become obsolete.
     
  14. jeffers

    jeffers Active Member

    Likes Received:
    31
    Trophy Points:
    28
    There will also be those who 'must have' when it gets launched.

    I will be surveying the fleet at my local club and we will (try) to tap LP up for a group discount.... ;-)
     
  15. whitfit

    whitfit Member

    Likes Received:
    1
    Trophy Points:
    8
    Isn't the complaint about the current sail that it immediately becomes obsolete after a few days of stiff breeze? In other words, if the new radial sail is the same in performance as the current sail when new, it shouldn't really change anything except allow people to keep their sails longer (for competitive purposes).

    What are we going to call the "radial" when both the full rig and the current radial rig both have radial cut sails? That will be confusing.
     
  16. torrid

    torrid Just sailing

    Likes Received:
    55
    Trophy Points:
    48
    That, and it is 3X the cost of a knock-off sail. A knock-off sail that isn't obsolete after a few days of stiff breeze.
     
  17. urbo100

    urbo100 Ian

    Likes Received:
    2
    Trophy Points:
    8
    IMO I don't think it would be long after the release of the Standard Radial cut sail that Intensity will produce a Radial cut "Training sail" for half the cost. This might be all the club sailer (like me) would want.
     
  18. jeffers

    jeffers Active Member

    Likes Received:
    31
    Trophy Points:
    28
    The problem is that the argument for people using the 'replica' or 'training' sails is more about longevity rather than price.

    I would be happy to pay the price for a 'genuine' sail if it lasted as well as my current 'replica' has.

    Plus if you get together with a few mates you may be able to get a bulk discount on 'genuine' sails. Here in the UK it is possible to get a price match with most of the common replica brands so the issue really is down to how long the thing lasts (IMO).

    Let us see what happens with the new sail.

    I for one can;t wait to try one out!
     
  19. sprayblond

    sprayblond Member

    Likes Received:
    2
    Trophy Points:
    8
    Surely, the new composite top mast must apply also to radial and 4,7.. Good news! :)
     
  20. jeffers

    jeffers Active Member

    Likes Received:
    31
    Trophy Points:
    28
    The new composite topmast is specifically for the Radial (a bad idea IMO). They would be better off sorting out the bending issues for the radial bottom section and investigating the bending issue some people are having with the top sections.
     

Share This Page