SJ23 Tech Tip F19, (Issued 1999-01-03) Tom Churchill

Index

Step the Mast Forward - to pass under a bridge.
"I wanted to step the mast by myself so I made a new symmetrical mast step for Malia.  A steel shop fabricated a new fitting for the foot of the mast from my cardboard template.  The new foot fits directly into a new deck fitting I fashioned after the original".  Tom Churchill.
 

TOM'S MAST STEPPING PROCEDURE - (Assume the mast is standing and you are going to take it down as in the illustration below).
  1. Connect the topping lift to the end of the boom.
  2. Next, tie the middle of a 30' long 5/16" nylon line to the end fitting on the boom.  This knot MUST NOT slip.  Run each free end through a hole in the toe rail adjacent to the mast, one to port and the other to starboard.  Take up the slack on each side line and tie it securely to another convenient hole in the toe rail.  You don't want this knot to slip either.  The two side lines passing through the toe rail holes must be able to run while stretching if needed, but must not be loose while stepping the mast.
  3. Next, using a 10' line with a small loop tied in the middle, tie each end to an aft cleat in the cockpit so the loop is positioned halfway between the cleats.
  4. Then, connect your mainsheet tackle between the aforementioned loop and the end of the boom. Your main sheet must be about 60' long for the 4 to 1 purchase.
  5. Finally snug up the main sheet, cleat it and loosen the backstay. The mainsheet is now holding the mast and one person can lower it by releasing the main sheet.
    NOTE: Once you've determined the length of your lines, (you have to experiment with this), mark them for future use.

Reverse the above procedure to raise the mast.

Aloha from Tom, Barb &   aboard Malia.

________________________________________

 

(Image of Catalina 25 is courtesy of Brian Smith, a long time sailing buddy)

 

 

The convenience of stepping the mast forward is that you can use the installed boom for mechanical advantage, saving time and effort.  You also have an additional safety factor in that the crew is not in the drop zone of the mast.  This might also be the fastest and most convenient method of lowering the mast for a fixed bridge!  I suggest, resting the mast on a 2X4 placed cross the compression posts of the pulpit.  If the 2x4 is equipped with a couple of blocks on top, they will provide adequate lateral support so wave action doesn't slide the mast sideways and twist the tabernacle loose.  Another plus is that the cockpit is clear to handle the boat while motoring.

NOTE 1: Lowering the mast over the bow can be done safely ONLY IF the boat has a hanked on jib.  Many roller furling manufacturers will void their warranty if the furler is lowered over the bow, citing damage.  Most furler manufacturers recommend you lower the mast over the transom to keep the foil straight.  The risk of damaging the foil by lowering over the bow is too great.

NOTE 2: The side support lines for the mast are called Morley Lines.  They come in various configurations to suit a particular mast.  Regardless of the configuration, their purpose is to keep the mast centered over the hull while stepping the mast.  To do so, the lines must remain snug for the entire arc of the mast to keep the boom centered over the mast, thereby controlling the mast.  While it would be ideal that the tie down points for the Morley Lines are at the same pivot point as the mast step, this is not the case for a SJ23.  Therefore, use a bridle to artificially raise the pivot point to that of the mast as described in Tech Tip f18.
 

Return to Tech Tip Index. . . . . . . . . . . . . . . Have a Question?