B&R Rig Tension

Discussion in 'Big Boats' started by Don Lucas, Feb 16, 2019. Add this thread to a FAQ

  1. Don Lucas

    Don Lucas

    Joined Jan 12, 2011
    773 posts, 28 likes
    Hunter 410
    US full time cruiser
    Recently had my mast on my 410 off. After it was reinstalled the tension seems a lot different (I had the rug inspected but I don't have a lot of faith in the rigger).

    My lower stay V1 is a lot tighter than before (still within 15-20% of breaking strength) but the lower inner stay D1 seems a lot looser than before. I can't find anything on how tight D1 is suppose to be.

    What is the tension others have?
     


  2. Will Gilmore

    Will Gilmore

    Joined Oct 19, 2017
    4,586 posts, 2,531 likes
    O'Day 19
    US Littleton, NH
    have you sailed her yet? What do the turnbuckles look like on the leeward side? How about your mast? Straight, bent, out of column? Rake is right? Your spreaders look normal, horizontal or maybe slightly angled upward?
    I'm not a big believer in the use of a gauge, I think performance is the telling factor, but if you are within the specs, you shouldn't have a problem.

    -Will (Dragonfly)
     


  3. ice breaker

    ice breaker

    Joined Sep 11, 2011
    246 posts, 29 likes
    Hunter 41
    US lake superior
    From the service manual. Might help.


    TUNING THE H41 B&R RIG
    PAGE 52
    The easiest method for tuning the B&R rig is
    to perform step one as follows before the
    mast is stepped, with it lying aft side down
    on two sawhorses. Begin with all rigging
    slack. If the mast is already stepped, loosen
    all the rigging, and then proceed to step
    one.
    1. Start with all the rigging slack. Then
    induce the mast bend by tightening the
    reverse diagonals (diamonds). Measure
    the bend by tensioning a line or the main
    halyard between the masthead and the
    gooseneck. The maximum amount of
    bend should be no more than 8”
    [203mm] for the standard rig and no
    more than 2” [50mm] for the furling
    mast. Measured perpendicular from the
    aft face of the mast to the halyard at the
    deepest part of the bend. It can be less
    than that based on the sail shape and
    your own preference. The bend should
    also be evenly distributed along the
    mast to give a smooth shape. Keep in
    mind that bending a furling mast may
    make it more difficult to furl and will not
    do much to flatten the sail as in a
    standard rig. It is very important that
    the mast also be straight from side to
    side at this time. Tighten or loosen the
    reverse diagonals to achieve this.
    2. Step the mast with all shrouds attached
    but with the turnbuckles completely
    loosened (if the mast was not already
    stepped).
    3. Attach the jib halyard to a cleat on the
    bow to support the mast in a raked
    position (the masthead should be about
    2’-0” [~6cm] behind the step). Attach
    the verticals and tighten them until you
    can just see the hole for the cotter pin
    in the turnbuckle. Tighten the jib halyard
    until you can attach the forestay. At
    this point the masthead should be raked
    so that a weight hung on the main
    halyard hangs about 1’ behind the mast
    step.
    4. Use the main halyard to check that the
    mast is centered from side to side. Pull
    it tight and mark the halyard next to the
    verticals chainplate. Now do the same
    to the other side to see if the marks line
    up. If not, tighten and/or loosen the
    verticals until the marks line up. Once
    the masthead is centered, begin
    tightening the verticals until the
    turnbuckles are approximately half
    closed. While tightening the verticals
    you may notice the bend in the mast
    increasing. Now you can tighten the
    lowers, which will tend to straighten the
    lower part of the mast. Be sure to
    tighten port and starboard sides evenly.
    5. Now you should tighten the headstay
    until it is approximately half closed as
    well. This should induce the appropriate
    amount of headstay tension. Never use
    anything more than a pair of wrenches
    to tighten your rigging. If you use an
    extended piece of pipe on the handle of
    a wrench you can over tighten the
    rigging and do damage to the mast or
    rigging.
    6. On the Hunter 41 it is necessary to go
    up the mast in a bosun’s chair to tighten
    the number 2 diagonal shroud (D2 or
    intermediate shroud). Always use
    caution when “going aloft”. You should
    always use a mountain climbing harness
    or Bosun’s Chair intended for this use.
    Always tie into the harness with the
    halyard using a bowline and then secure
    the shackle as a back up as the knot is
    more reliable than a mechanical
    fastener. The person hoisting you aloft
    should keep the halyard stopper closed
    to prevent falls. Good communication
    between the two of you is also
    important. Tighten the D2 until it has
    just become tight and then add two
    complete turns. While at the first
    spreader, look up the back of the mast
    to see if it is straight (rather than bent
    from side to side). If it is not straight
    then adjust the appropriate D2 to
    straighten it.
    7. Have the person on deck carefully lower
    you. They should keep the halyard
    wrapped at least twice around the
    winch and should always have one hand
    able to stop the halyard from running
    free. Once on deck look up the back of
    TUNING THE H41 B&R RIG
    PAGE 53
    the mast and see if it is straight (rather
    than bent from side to side). If not then
    adjust the lowers (D1) until it is.
    8. If you have the standard rig you need to
    attach the struts at this time. Attach
    the lower end of the strut to the smaller
    hole in the chainplate. Adjust the length
    by turning the ball joint bearing in the
    upper end of the strut until the holes in
    the pin can be attached. It is normal to
    have some play between the strut and
    the chainplate and strut bracket
    9. The final test is to go sailing in 10-15
    knots of wind. If when sailing upwind,
    the shrouds on the leeward side are
    slack then tighten them to remove
    about half the slack keeping note of the
    number of turns. Then tack and do the
    same to the other side. Do this until you
    are happy with the tension and the
    leeward side does not get loose when
    the boat is heeled. Now sight up the
    mast to be sure it is still relatively
    straight from side to side. If it is not
    then adjust to appropriate rigging to
    correct it. For example: if the mast is
    straight until the upper spreader and
    then hooks to the windward side then
    you will have to revisit steps 6 and 7
    above. Remember to always tighten the
    leeward shroud, tack and tighten the
    new leeward shroud the same amount.
    This prevents damage to the
    turnbuckles and is also much easier to
    do. Keep in mind it is also possible to
    have something too tight such as a
    diagonal shroud.
    10. At this point you should have adequate
    headstay tension. The sails are built for
    an average of 14” [350mm] of headstay
    sag, possibly more or less depending
    upon light or heavy air. The bend in the
    standard mast should be about 4”
    [100mm] and 1” [25mm] in the furling
    mast and it should be nearly straight
    from side to side when sailing upwind.
    If any of these are not true then revisit
    the appropriate step above to correct it.
    If the sag in the headstay is too much
    then adding tension to the verticals will
    fix it.
    11. Once the rig is tuned you should make
    sure to add the cotter pins to all the
    rigging bending back the ends and
    taping them to prevent snagged lines,
    sails and fingers.
    Remember that rigging, like everything else,
    can age. As it gets older it may need to be
    replaced. The frequency for which this
    becomes necessary depends on the climate
    and conditions in which the boat is sailed.
    For example: if you sail in the Caribbean it
    should be replaced every 2-3 years
    compared to every 10 for the great lakes.
    You should consult a professional rigger for
    advice.
     


    Will Gilmore likes this.
  4. Don Lucas

    Don Lucas

    Joined Jan 12, 2011
    773 posts, 28 likes
    Hunter 410
    US full time cruiser
    I believe in things that can be measured.
    I have the manual, but thanks for posting it. It says nothing about the question I asked.
     


  5. DayDreamer41

    DayDreamer41

    Joined Oct 29, 2016
    1,321 posts, 657 likes
    Hunter 41 DS
    Un Port Huron
    Here are a couple of useful instructions from a Selden Mast Manual
     

    Attached Files:



    DrJudyB likes this.
  6. dehler25

    dehler25

    Joined Sep 10, 2012
    206 posts, 13 likes
    Hunter 450
    US Gulfport, Florida
    When I had my mast removed for inspection and rerigged it was to the aforementioned instruction, unfortunately the rigger mounted the forestay on a hollow aluminum spacer rather than the 5/8' solid ss pin, the subsequent rigger noticed that the mast bend spec'd was rather profound for the furler to rotate smoothly and relaxed the tension. Keep in mind the straight furler will not rotate cleanly in a bent housing.
     


  7. DayDreamer41

    DayDreamer41

    Joined Oct 29, 2016
    1,321 posts, 657 likes
    Hunter 41 DS
    Un Port Huron
    Relaxed the tension on the forestay? or the diagonals? I have seen a couple of different rig tuning directions by Selden, one states that the prebend should be 1% of the measured distance from the gooseneck to the mast head and another is no more than 1" prebend for a mast with in mast furling, keep in mind both sets of directions were for an in mast furling setup. As mine is now it appears to have at least the 1% prebend, but I plan on taking the mast down in the spring doing an inspection and restepping, which would be a good time to make adjustments to the diagonals. It sure would be nice to know exactly what those adjustments should be. Towards the end of last season the main sail would often give us trouble unfurling as it appeared to bunch up at the top of the mast and once the folding over started it would bunch the sail up much of the way down causing it to jam when unfurling. I attribute much of this issue to an 10+ year old sail, but I would think that too much prebend would also come into play.
     


    Last edited: Feb 18, 2019
  8. Don Lucas

    Don Lucas

    Joined Jan 12, 2011
    773 posts, 28 likes
    Hunter 410
    US full time cruiser
    So:

    No one knows how tight their D1is compared to their V1 stay?
     


  9. DayDreamer41

    DayDreamer41

    Joined Oct 29, 2016
    1,321 posts, 657 likes
    Hunter 41 DS
    Un Port Huron
    @Don Lucas I would think that the D1 and V1 tension is determined by the prebend and mast cross sectional resistance and not necessarily repeatable from mast to mast. Short answer, no I don't know what they are and the instructions indicate that its really not measured other than the how they effect the mast shape.
     


    Will Gilmore likes this.
  10. Don Lucas

    Don Lucas

    Joined Jan 12, 2011
    773 posts, 28 likes
    Hunter 410
    US full time cruiser
    all you have to do is go outside and shake them and report back
     


  11. DayDreamer41

    DayDreamer41

    Joined Oct 29, 2016
    1,321 posts, 657 likes
    Hunter 41 DS
    Un Port Huron
    @Don Lucas I can tell you without going to the boat that they are tight, maybe too tight but they are tight
     


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  12. Don Lucas

    Don Lucas

    Joined Jan 12, 2011
    773 posts, 28 likes
    Hunter 410
    US full time cruiser
    So you don't know but have a feeling they have an issue??????

    Mine are "tight". I even know how "tight" mine are, but have no idea really what "tight" might mean by itself.
     


  13. Will Gilmore

    Will Gilmore

    Joined Oct 19, 2017
    4,586 posts, 2,531 likes
    O'Day 19
    US Littleton, NH
    That is the crux of the entire rig tuning issue, right there. It's about the whole design, not about the cables or the gauges.
    Make them as loose as they can be and still do their jobs under sail to put the least amount of stress on every part of your boat. If they are a little over tight, no big deal.
    If they bend the mast in unwanted ways or allow too much movement, they need adjusting. Loosen stays to get a bend out, tighten them to stop slacking or movement.

    -Will (Dragonfly)
     


    JamesG161 likes this.
  14. DayDreamer41

    DayDreamer41

    Joined Oct 29, 2016
    1,321 posts, 657 likes
    Hunter 41 DS
    Un Port Huron
    @Don Lucas what I have read is the D1's (lower inside shroud) should be tensioned to 20% of breaking load. The V1's which should be the first shrouds to be tensioned are loaded to 15-20%.
    Now if your rigger did not set the prebend correctly what may be going on is V1 cap shrouds were tensioned causing a slight increase in prebend, but when bringing the D1's to tension the prebend was gone, he would then have to slacken the D1's off allowing the mast's set prebend to return.
    I am told that setting these masts up is tricky and there is a bit of trial and error to get the D1 & V1 tensions correct while maintaining the desired prebend to the mast.
    EDIT: Don, I have to admit I did not initially read your question close enough and went right to the tuning lane, while all you were really looking for was input on the inner shroud.
     


  15. Don Lucas

    Don Lucas

    Joined Jan 12, 2011
    773 posts, 28 likes
    Hunter 410
    US full time cruiser
    Well a little research will show that is not right. Loose rigging will result in more stress on the boat that tight rigging.
     


  16. Will Gilmore

    Will Gilmore

    Joined Oct 19, 2017
    4,586 posts, 2,531 likes
    O'Day 19
    US Littleton, NH
    I haven't seen that concept presented before. I'll check into it. Perhaps there is too much ambiguity in the phrase I used,
    I don't mean make them loose. Only that the tighter you make a cable, the more stress is put on the cable, the shorter the life of the cable and all parts attached to them.
    I can't see how doubling the tension on a chainplate, for example, will be less stressful. Reducing movement, definitely.

    -Will (Dragonfly)
     


    JamesG161 likes this.
  17. JamesG161

    JamesG161

    Joined Feb 14, 2014
    3,603 posts, 1,320 likes
    Hunter 430
    US Waveland, MS
    I agree.
    Even a good rigger needs to tune the first pass rigging when under away with sails up.
    I didn't chime in before, but the solution is complex.

    Ans: Get a good rigger who understands your boat.
    Jim...

    PS: BTW your H410 is not like my in mast furling H430 either.
     


  18. Will Gilmore

    Will Gilmore

    Joined Oct 19, 2017
    4,586 posts, 2,531 likes
    O'Day 19
    US Littleton, NH
    I thank you guys for your support, but really, it wasn't that bad. It's Don's thread, he asked for experienced advice and I chimed in without such advice. I have opinions and ideas and a sense of understanding, I don't hesitated to share. I hope my participation has prompted thought and learning around this subject. It has helped me. That's all I need say on the subject, for now.

    -Will (Dragonfly)
     


  19. Don Lucas

    Don Lucas

    Joined Jan 12, 2011
    773 posts, 28 likes
    Hunter 410
    US full time cruiser
    gee everyone has an opinion about pushback for a response that wasn't about the question, but no one has any idea of their B&R rig. Do you guys also response to Catalina specific questions with a story about your Hunter?

    BTW - a "qualified" rigged is how I got to asking this question. His "qualified" adjustment is different than the last "qualified" guys. At the same time he put these cotter pins in that are so long they might be called weapons.
     


  20. Jackdaw

    Jackdaw

    Joined Nov 8, 2010
    10,060 posts, 3,072 likes
    Beneteau First 36.7 & 260
    US Minneapolis MN & Bayfield WI
    A boat you've never seen, a rig you've never sailed, and yet you have more comments and advice here than anyone else. Maybe its time to learn that listening without speaking can be a great way to learn, and build respect.
     


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