MENU Member Login
On the waterfront in Downtown Toronto since 1894 From novice to old salt, there is a place for everyone at National Yacht Club.
Hillbilly Mast Tuning
June 26th, 2013 @ 12:47 PM EST by admin

submitted by Paul Bond.

The goal:  Mast straight at rest w/ no backstay tension; top of mast bending rear some 6″ under full backstay tension in a smooth bend of the upper half.  Forestay sag should be adjusted to preference and sail cut, but 10″ play at the center under no backstay tension, and 3″ or 4″ under full backstay and heavy wind works.  Cooler should be ready.

  • Start with all shrouds slack, ice in cooler.
  • Get a beer.
  • Measure side-to-side straightness with a Spin Halyard to the chain plates, adjust outside main sidestays until straight.  (Mast should be roughly straight side-to-side, or you may have to adjust your deck shims).
  • Tighten main sidestays an even amount ot turns, both sides.  Make them fairly tight (they will loosen as you sail the first time).
  • Another beer.
  • Bring all baby-stays to loose, even tension (not floppy).  Mast should still be roughly straight.
  • Tighten all baby stays an even amount of turns, not as tight as main sidestays, but tight.  Check mast for bend  by looking up main track- should still be almost straight.  Adjust whichver baby stay needed to make it straight (fore-aft, right-left)
  • Take up full tension an backstay.  Backstay is adjustable some 8″.
  • Mast should now be bent some 6″ rearward at the top, a gradual bend down to spreader.  Side-to-side should still be straight.; rear baby stays are slackened, front  baby stays additionally tight.
  • Better get another beer, this may take a while.
  • Adjust baby stays to make mast straight side-to-side under all conditions.
  • Release backstay, and adjust Forestay for Max Sag.  Don’t carry beer forward of mast, unless you have plenty.
  • Check it all 2 or 3 times, adjust.  Have a beer.
  • Take it for a sail, and be ready to adjust some more, as shrounds loosen up under load.  If top is bending away, tighten main side shrouds first.  Set beer between halyards near the mast (very secure there).  Hot tip:  leeward shrouds are easier to adjust.
  • Check it again at the dock, over a beer.
  • Check it again during mid-season.
  • Replensih cooler regularly, or your crew will desert.