SJ23 Tech Tip A07, (2020-01-23) Bob Schimmel


Support the Mast - For Road Travel or Winter Storage.

It's been said many times that the majority of damage done to a boat is while it's on a trailer.  The hull experiences a considerable amount of stress with every bump, dip and turn of the road.  This includes the mast as well.  Whether you tow the boat or store it for the winter, a well supported hull and secured mast is essential.  Below are examples of good mast support with secure tie down lines.

BOW SUPPORT - The mast crutch on the pulpit should be placed just AFT of the pulpit forward posts, NOT ahead of them on the unsupported lip.  Resting just aft of the compression posts provides the greatest strength and stability.  Many times I've seen a mast supported by the lip (forward of the pulpit posts) and wondered why the owner can't figure out why the pulpit is suffering from "droopy lip syndrome."  The unsupported lip is not designed to handle the shock pounding of carrying a mast while driving down the highway.  Eventually the lip will droop, which looks pathetic.  Place the (2x4)" support across the pulpit just aft of the forward posts and tie it to the pulpit with a square lashing.  Then tie the mast around the wood support with a square lashing to prevent movement.  If you don't know how to tie a square lashing, ask a Boy Scout!  
PS: The mast must be wrapped with rug at the bow to protect the anodized finish.  The rug was eliminated in this photo to show the knots.  TOP

MID MAST SUPPORT - If the poor bow support described above isn't bad enough, the same people also tend NOT to support the middle of the mast. Drive alongside a sailboat on the highway sometime and watch the middle of an unsupported mast flex.  It's amazing that more masts don't snap under these forces and that the pulpit can take this much abuse.  The compression post shown at left, along with the lateral tie down lines, support the mast very well.  Either support is within the capability of the "weekend expert" to fabricate.  Coat the wood with your favourite stuff to keep the water out. 
The mast must be wrapped with a rug at the mid support to protect the anodized finish.  The rug was eliminated in this photo to show the knots.  TOP



TRANSOM SUPPORT POST - Fabricate a steel mast support post such as the one shown at the right to support the mast at the transom.  This post is fairly easy to make from 1" square steel tubing, provided you can weld or find a welder.  The beauty of this post is that you can still climb onboard over the transom, something I find very useful during winter. 

  • The yoke at the top is made of  1/4" thick by 1.5" wide flat iron welded to the top of the square tubing.  It is 4" wide across the opening to receive the mast and 4" deep to prevent the mast from rolling out.
  • The yoke is lined with short pile rug to protect the mast.  The rug is attached with tie wraps so it stays in place as the mast is lifted out or slid aft.
  • A roller in the yoke is really convenient for sliding the mast.  If you decide to add one then cut the top of the yoke even with the roller so the mast tangs can slide past.  You'll still have to tie the mast to the yoke for road travel.  In 2018 I replaced the yoke on this post with a roller and made the post telescopic.  See Tech Tip F18
  • Fabricate the pintles from 3/8" rod (same size and position as your rudder) bent to shape and welded on.  Alternatively they can be made from a 3/8" bolt so you can spin a nut on the bottom to tighten the support bar to the gudgeon, which is actually a good idea.  Although mine are made from 1/4" rod which have served me fine.  It is absolutely crucial that BOTH pintles bottom out at the same time on their respective gudgeons to distribute the load equally.  Make the bottom pintle (2") long and the top one 1.5" long.  A longer bottom pintle facilitates easier installation, similar to the rudder.  The pintles are placed 17 7/8" apart along the post, same as the rudder.  In the photo at right note that the end of the bottom pintle is just short of the end of the bar.  This protects this pintle from bending during storage. No don't use it to break up the ice around your boat!
  • The post is bent 200 aft 25" up from the bottom.  The upper 39" of the post is vertical to support the mast.
  • Paint the post black to prevent rust.  TOP

When the post is set on the gudgeons it will flop to one side making it impossible to place the mast in the yoke.  Therefore, the top of the post must be tied across the transom to the toe rails, cleats or pushpit so the yoke it aligned to the mast.  Examine the photo at right closely. 

  • The white line wrapped around the pintles is used to secure the post down on the gudgeons to keep it in place when trailering or stepping the mast. 
  • Fore and aft support is not required as that happens automatically when the mast is tied to the pulpit. 
  • The loop of green line coiled from the bottom of the yoke is actually two lines.  One goes to each corner of the transom to secure the post sideways. The white line is used to secure the mast inside the yoke. 
  • I usually store this bar with the trailer when the boat is in the water so I don't have to go hunting for it in the Fall.  The lines always remain attached to the post so I don't have to figure out this system on the ramp.  A place for everything and everything in its place! 

When you lay the mast in the yoke remember to remove any shrouds or halyards from inside the yoke.  This ensures you don't damage the anodized finish on the mast or the rigging.  

There is only one short coming with this metal support post; I can't place the rudder in the gudgeons to steer the 20KMs down the lake with the mast down.  Steering with the outboard's tiller is pretty well an exercise guaranteed to kink your neck and tick off the crew as you zig zag down the lake.  It is next to impossible to steer a straight line.  In this case it is far better to have a wood A-frame support frame that straddles the tiller so you can still steer with the rudder. 
PS:  A secondary problem with motoring with the mast down is that you have removed the primary drive system (sails) of a sailboat and are totally dependent on the backup drive (engine).  I've seen several sailboats run into serious trouble using this logic.  Don't lower the mast till you get there! 

COCKPIT WOOD SUPPORT FRAME - If you can't find a welder to make a metal support post you can fabricate a very secure post from dimensional lumber.  Make an A-frame and rest it on the cockpit sole, 1' forward of the drain holes.  This is directly above the bulkhead support located under the cockpit.  The A-frame must not block water flowing to the cockpit drain holes.  It is all too easy to think you don't need them in winter but the reality is otherwise.  Some people solve this problem by resting the stand across the seats or raising it on feet so water can flow under it. 

NOTE - One advantage of a cockpit supported wood A-frame that rests on the seats is the rudder and tiller can be used to steer the boat with the mast laying down.  This can be very convenient for motoring the boat to the ramp at the end of the season. 

One could argue that a wood support frame standing in the cockpit is easier on the hull than the metal transom support post resting on the gudgeons.  In practice I always keep my support lines tight while towing and during winter storage to prevent movement.  The gudgeons have never flexed or leaked.  The metal post is smaller and lighter to store and I can, with a bit of contortion, crawl around it to get into the cockpit when the storage tarp is on. 

The system shown here is yet another home made version to support the mast.  It works because of the split pushpit.  I notice that this owner has added many features from various Tech Tips.  Sweet.


This is Bill Ward's design for supporting the mast at the transom.  He hooked the strap to the toe rail and wrapped it over the mast to keep the mast centered over the cockpit.



SPREADERS, SHROUDS & HALYARDS - I detach Panache's spreaders for winter storage since they would protrude into the tarp.  It is easy to remove the two screws (screw them back in the holes they came from for storage) and lay the spreaders on the deck (just aft of the mast step) lashed to each other so they don't move.  The shrouds are pulled forward to remove any slack and lay on the cabin top where they don't move.  For a long road trip I lash them to the hand rails to prevent movement.  The backstay is coiled and tied to the mast hanging over the cockpit.  The forestay and halyards are pulled tight along the top of the mast and tied every 2' with shorts lines dedicated to this purpose.  None of this rigging moves with the wind at highway speed.  

HINT:  Make a haul out storage bag to store all your tie down lines, including the three mast supports.  I keep it tucked in the bow, handy for haul out.  Include a small plastic bottle to hold important screws and pins.  This way you have only one place to look for your haul out stuff.

Happy hauling!  TOP

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