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  • #4456

    Dear All

    bit of a racer-question here.

    After a race in my boat with my friend Charles who is an expert racer (several dinghy classes and yachts, but not W’s) I’ve suddenly caught the racing bug. (with no loss of enthusiam for other forms of W-sailing I hasten to add) Anyway, this race was in light F1 “gusting” 2 and Charles felt the bridle was too slack, and that that boom needed to be right near the midline when close hauled. Then last night my son and I flogged around a tricky course in a good brisk F4-5 and wished we’d not shortened the bridle a bit: as we then couldn’t emulate the picture in the W-book of a flat sail on a boom nearer the quarter.

    This has raised some interesting issues:
    when I shorten the bridle down to bring the sail anywhere near midline I end up with a lot of “kicker” functionality in it – it is pulling down on the boom end. I can’t see how this can be avoided. Can it? Is the midline in fact a sensible place for a W boom to be when close hauled in lighter winds?
    second: trying to acurately tie the pair of bowlines is an awful job – in fact I’ve just sent off from some clamcleat Line-lok cleats to try and make creating equal sides a reasonable possibility!.

    so how to people set these up without going bonkers? Is there a magic formula or set-up proceedure one can follow?

    cheers all

    Boris W6330 “Delphy”

    #10898
    Davdor7038
    Member

    Hello Boris, although not a very experienced “racer”, with only a few races in light winds, what I have found is that the best guide to correct boom trim, are the telltales on the back of the mainsail leech.

    Ideally, these should be blowing straight back with an occasional fall-off to leeward. This means that the airflow is being diverted backwards which helps create thrust in a forward direction. Action and Reaction, I think. Initially, I had been sheeting in too tight, and getting the boom into the centreline, and losing lots of ground to other boats. The telltales were constantly to leeward, When I eased the boom out toward the quarter until the telltales were more or less blowing backward, I stopped losing quite as much ground. This does change constantly, meaning to keep them blowing backward, I have to constantly check the trim. If the telltales are to leeward most of the time, this means the airflow on the leeward side of the sail has stalled,is falling away and going sideways and not rearward and thus reducing forward thrust.
    This reflects both my very limited experience and what I have read on the WIT site. I can’t help you with heavier winds as, as yet, its either been v light winds or too much wind for even the experienced laser racers to go out.

    As to the length of the bridle and how to fix it, Uncle Al (on the WIT site) recommends loads of half hitches with an occasional check. I too am interested to know what is the best option as done by far more experienced sailors. Regards, Dave

    #10904
    Geof
    Member

    You have correctly observed that the leech of the main can be significantly affected by the bridle.

    In a force 4-5 the kicker should be doing the work to control the leech with the bridle short and not really influencing things.
    In lighter wind then having the boom on the centreline is good for pointing and provided the jib is set to complement this then is very fast. Adjusting the bridle so that the leech of the main is just tight enough when the boom is on the centreline is well woth while.

    #11050

    Just an update on this:

    the Line-lok cleats (by clamcleat) are fab – it makes it very very easy to adjust the bridle. They seem to be used mainly for tents and tarps, but are great for this application. I bought them on Ebay as I couldn’t find them elsewhere and certainly not in any chandlers. For instance our last sail was in light airs, but our next (a race) will be in a F4 – 6 if the forecast is correct: adjusting the bridle very accurately will take about 30 seconds.

    Having found a cheap(ish) fiddle block on Ebay I in fact have two bridles – one for rear sheeting and one for centre sheeting. It takes about 3 minutes to change the bridles over and the Line-lok’s mean its very simple to even it up to centralise the blocks. I did this so it would be easy to change the configuation of the boat to accomodate “guests”. We are all tall in our family and 4 is a real crowd with centre sheeting.

    Also I’ve been experimenting with bringing the bridle forward when sailing with an outboard on the transom (during a lovely but very windy week on the Fal two weeks back). On a Mk1 bringing the bridle forward to near the front of the rear tank is too far forward – yes the sheets don’t get tangled in the motor or quarters, but they certainly get tangled in the forward two clips of the tank hatch on my boat. I’ve come the the conclusion the best compromise for cruising with a motor on the transom is to put the bridle (and boom block) about level with the back of the bouyancy tank hatch, but I’ve yet to try it. I’d be interested to hear views on that.

    happy sailing folks

    Boris

    #11051
    Dave Barker
    Keymaster

    @Andrew Morrice wrote:

    I’ve come the the conclusion the best compromise for cruising with a motor on the transom is to put the bridle (and boom block) about level with the back of the bouyancy tank hatch, but I’ve yet to try it. I’d be interested to hear views on that.

    I’d say that’s about where we have our boom block (no bridle though). I have added a spacer block (plywood sandwich) to the engine mounting pad to position it slightly further astern, and we also use a cheap engine cover when the outboard is raised to horizontal in order to prevent the choke and starter knobs from snagging the mainsheet during a gybe.

    #11052
    Swiebertje
    Participant
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