Latest News: Forums Technical Time to replace the Outhaul ?

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  • #3804
    Anonymous
    Inactive

    I have a single 4mm line entering at the gooseneck end which finishes on a single block inside the boom.. A seperate line goes around this so at the aft end of the boom I am getting 2:1. I also get 2:1 as the mast end of the boom line divides so that I have the conventional racing adjustment of thwart mounted cleats. I have never replaced the lines in 4 years but often have the problem of struggling to get the clew to the marker on the boom. Following the mainsheet and halyard post should I assume
    1. the 4mm lines need replacing as they have developed a twist from repeated tensioning/release (I know I need to move the wear points by trimming a little off the ends). I am sure there is friction inside the boom.
    2. the rope inside the bottom edge of the sail has shrunk
    Thanks in anticipation
    Dave

    #7352
    Anonymous
    Inactive

    One sneaky trick to double the mechanical advantage is instead of simply shackling the outhaul line onto the clew of the sail, take it through the clew and then tie it back to the end of the boom on the opposite side, so the clew cringle acts as a pulley. This will give you an effective 8:1 which should be spot on for an outhaul.

    Do the sheaves in the boom turn freely? The metal sheaves generally used for the line to exit the boom at the outer end are notorious for seizing.

    To check the foot rope in the sail, try pulling the foot along to the black band by hand (ie grabbing hold of the clew directly, not via the outhaul). It should be reasonably easy to pull it more or less to the black band like this, if not either the track slides or foot rope are tight in the boom slot, or else the foot rope has shrunk, (as per the other thread on halyards).

    The reason for a tackle is to allow you to easily pull the foot along the boom against the wind load in the sail, not because the foot is hard to stretch out flat.

    #7355
    Swiebertje
    Participant

    @John1642 wrote:

    The reason for a tackle is to allow you to easily pull the foot along the boom against the wind load in the sail, not because the foot is hard to stretch out flat.

    Also to have more travel, it is much easier to pull the foot another half inch by pulling 4 inch of rope rather then pulling 0.5 inch. Sometimes we have lots of purchase not because we need the force but to allow for very fine control.

    Another trick is to lubricate the sail and/or groove with Teflon spray. Or use the old fashioned (and time proven) candle stump method. (I do it once every year). And while you are at it, also lubricate the luff and/or the mast groove. BTW, never use silicon lube spray! Its rubbish!

    #7356
    Dave Bevan
    Member

    @Dave Mac wrote:

    I have a single 4mm line entering at the gooseneck end which finishes on a single block inside the boom.

    Hi Dave.
    I may have misunderstood, but if you’ve got a single line going to the block from the gooseneck, I think you’ve got 1:2, not 2:1 in the boom – this will cancel out the 2:1 you get from the split control.
    To get 4:1 on mine, a line is fixed on the outboard end of the boom, and goes around a block with hook that attatches to the outhaul clew, and than back to a sheeve on the end of the boom (2:1) and it’s fixed to a block about halfway down the boom. Another line is fixed on the gooseneck end of the boom, which goes around the block in the boom, and back to exit at the bottom of the boom with a cleat just behind the gooseneck (another 2:1) – I don’t have split control.

    #7358
    Swiebertje
    Participant

    @Dave Bevan wrote:

    I may have misunderstood, but if you’ve got a single line going to the block from the goose neck, I think you’ve got 1:2, not 2:1 in the boom – this will cancel out the 2:1 you get from the split control.

    I have made a small sketch to explain:

    The first 2:1 purchase is at the block along the mast. The second 2:1 purchase is inside the mast and the third purchase is at the sails cringle. Together it is a 8:1 purchase. Though you don’t actually need the force of a 8:1 purchase it allows fine adjustments. An 8″ pull makes the sail move only 1″.

    Except for the block along the mast and the SB & port control lines, this is how new Wayfarers are setup by the builder. The builder exits the control line through the bottom of the boom near the goose neck and leads it through a clam cleat and a small block. The block forces the line in the cleat regardless in what direction the end is pulled. However, many sailors prefer SB & port control (and the extra purchase) and add a block as shown by the drawing.

    On my boat I have a shackle with a small block at the sail’s tack. It makes the outhaul run much smoother. The shackle is one of those long types because the cringle is some distance away from the sail’s edge.

    #7359
    Anonymous
    Inactive

    Swiebertje……..a great diagram! Thanks. I will post my own set up very soon which is similar but different and may or may not have a 2:1 or 1:2, I”ll let you decide. I suspect its a “correct” system as I’ve never touched it and was led to believe the previous owner was a very competent racer. I suspect my issue is seized blocks etc but I also wondered whether old lines might develop a twist and then cause friction, but no-one has picked up on this. Will update soon with a diagram. Thanks to all so far. Dave

    #7360
    Dave Bevan
    Member

    Thanks Swiebertje,
    Your sketch shows much better than I was able to explain.
    Initially, I just tied-off the outhall to the end of the boom, but my setup is now very similar except I don’t have a split control and it exits to a jaming cleat under the boom instead.

    I’ve tied the ends off with a few inches spare to allow for wear & adjustment (I realised this summer that I was carrying about 10′ of spare line in the boom!).

    My sketch isn’t quite up to your standard though!

    #7361
    Swiebertje
    Participant

    @Dave Bevan wrote:

    my setup is now very similar except I don’t have a split control and it exits to a jaming cleat under the boom instead.

    That is exactly how the builder delivers new boats and what I tried to describe. Again you have proven a sketch is much better then text to explain these details.

    And Dave Mac, before you go on a shopping spree, I would suggest to take the block from inside the boom and clean it with fresh water and maybe some soap. Then lubricate it with Teflon (PTFE) spray. There is a good chance it will run smooth again for another few years.

    If the rope work is undamaged, put it in a pillow cover or in a (cotton) sail bag and wash in your laundry machine just like your clothes. Washing will take all the salt out and most of the dirt. In my experience a rope only needs replacement if it is damaged (i.e. chaffed). And even if it is damaged, cutting a few inches of the end may give it a new life again.

    BTW it may be an idea to put all other all ropes in the same pillow cover too. I wash my ropes at the end of every sailing season, just before everything goes into winter storage.

    #7362
    Anonymous
    Inactive


    Thought a photo might be quicker but lets see if its worked.
    Inspected all the blocks and they are running free so going to play with the sail in the track. The line doesn’t look too bad to me
    Dave

    #7363
    Anonymous
    Inactive

    @Dave Mac wrote:


    Thought a photo might be quicker but lets see if its worked.
    Inspected all the blocks and they are running free so going to play with the sail in the track. The line doesn’t look too bad to me
    Dave

    If the outhaul is rigged the exact way your sketch shows then someone has indeed made a bit of a mistake! The block inside the boom is actually halving the purchase instead of doubling it.

    Compare it carefully with the first sketch posted and you will see the difference – in essence the block in the boom needs to be fixed to the end of the tail leading to the clew, ie pointing the other way around.

    What you actually have there is an outhaul with an overall 2:1 advantage (ie 2:1 x 1:2 x 2:1) but with all the extra friction of the blocks moving back and forth. What you will have if you re-rig the block in the boom is 8:1 (ie 2:1 x 2:1 x 2:1).

    #7364
    Anonymous
    Inactive

    Years ago my boat was incorrectly rigged by the builder as per your photo above. It’s easily corrected to that shown in your first diagram. Sometimes the builders get it wrong!
    Toby

    #7365
    Anonymous
    Inactive

    Many thanks all, and Dave hats off for initially spotting the detail in my post without a sketch! Problem being sorted as we write and already without mounting boom in boat a pull from the mast end by hand is feeling more effective. Moral of the story…….if you are using brute force you’re doing it wrong. Its only taken me 4 years to sort this one. Thanks very much Swiebertje and John too. Cheers Dave

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