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Mast Upgrades and Maintenance
This page was last updated on 4 April 2003.

New Masthead (Anchor) Light
New Spreader Bases  |   Standing Rigging Maintenance and Inspection  |   New Jumper Stays  |  Boom Support Cable

Spreader Bases

I decided to replace my original cast aluminum spreader bases after a damaging incident during our 2002 cruise.  During a raft-up with a friend's Triton, an inconsiderate powerboat sped by at "maximum wake speed", causing the masts on our two boats to collide several times before the wake settled down.   The impact sheared one of the spreader bases on our friends' boat, calling into question the structural integrity of our own spreader bases--even though they looked OK.  To play it safe, I decided that 40 years was ample service for these parts, so I ordered a new set from my local rigger.  He found a place where these castings are still a stock item; I cannot remember the name.  

oldbeneath.JPG (164654 bytes)The new bases are nearly identical to the old, although the wall thickness of the spreader socket is thicker than on the original (always a good thing).  The castings came with no holes drilled, so I'll have to take care of that.  

Removing the old bases from the mast was easy, a matter of unbolting two stainless steel bolts, which were fortunately in excellent condition.  Despite a weathered appearance on the visible parts of the old bases, they looked generally sound at first.  Once I removed them, however, it became clear that they had been operating on borrowed time.  The back sides of the bases, where they had rested against the mast all those years, were quite badly corroded and chalky in appearance, as one might expect after 40 years of outdoor marine service.  Nothing particularly alarming, but deteriorated enough that I was unquestionably happy that I had taken the time to remove them.

Once the boat was back home in the backyard, I brought the rigging into the shop for storage, and at that time tried the fit of the new spreader bases with the existing spreader tubes.  The tubes didn't fit into the new sockets, though it was close.  I determined that the problem was with the roughness of the casting, rather than a complete misfit, so I stored the stuff out of the way for the moment with plans to bring it all out during the winter and make the necessary adjustments. 

insocket.JPG (161171 bytes)When I finally did begin work on the new bases in earnest, I found that it took very little work with a file, first, and a small drum sander attachment in my drill to remove the casting burrs and ream the sockets out enough for a good fit.  Once this had been done, each spreader fit home with a satisfying clunk as it hit the bottom of the socket.  I spent some extra time cleaning up the spreader tubes, removing the rubber spreader boots (which had been in place for two seasons), and cleaning up the spreader tip castings.  I even unscrewed the flag halyard eyes from each spreader and reinstalled them with a good coating of waterproof grease at each screw location, to help isolate the stainless steel screws from the aluminum.
crack.JPG (190360 bytes)With the fitting work complete, I took a moment to scrape off the crusty corrosion from the old bases and clean them up for inspection and storage as spare parts.  While doing this, I noticed a couple alarming things about the bases that made me extra happy about installing new replacements.  First, on both parts, there were some casting inconsistencies on the back sides, air pockets in the metal that just didn't look encouraging.  And, more seriously, on the starboard spreader base, I noticed--upon close inspection--a hairline crack along the top edge of the juncture between socket and base.  The crack extends over most of the top half of the socket, and is quite hard to see.

This is exactly the sort of crack that leads to catastrophic failure someday if it's not noticed, and it scared me to realize that, had it not been for our mast-banging incident during our summer cruise that led to the failure of our friends' spreader base, we might not have been inclined to replace the bases, at least not unless a close routine inspection had located this crack.

I am now aware of several Tritons that have recently suffered spreader base failures, probably caused by similar casting flaws like this.  I guess that these relatively poor (to begin with) castings have just about seen all the stress they can handle after 40 or more years, and simply fail under not-abnormal strains.  Beware!

Later, I carefully drilled the boltholes for securing the bases to the mast, using the old spreader bases as a guide, and also drilled for the cotter pin that holds the spreader tube inside the base.  Creating these holes was a matter of careful measuring, remeasuring, and measuring again; the aluminum cut easily.

newspreaderbases42103.JPG (142611 bytes)Several weeks later, I installed the new spreader bases on the mast, bolting them in place with the original bolts (which seemed to be in good condition still).  I applied a thin coat of waterproof grease to the underside of the bases to help isolate them from the mast.

Standing Rigging Maintenance

In the fall, I removed all the standing rigging from the mast after it was unstepped.  I carefully coiled each wire and stored them in the shop for later inspection and maintenance.  During the winter, I pulled out the wires and began some basic maintenance.  Mostly, I worked on a general wire inspection, concentrating on the condition of the swages but also carefully inspecting the wires for signs of damage or broken strands.  I also lubricated the turnbuckle threads with some of my new favorite waterproof grease, which I now use all over the place.  By unscrewing both ends of the turnbuckle all the way, and then spreading a small bead of the grease on the threads and then screwing them in all the way, I achieved a consistent, thin coating of the grease on all the threads.  Not only will this make the turnbuckles easy to adjust and prevent them from freezing, but it will also protect the threads from corrosion and salt spray.  

omctripleguard.JPG (175254 bytes)I use a blue waterproof multi-purpose waterproof grease on the turnbuckle thread, as well as on many other onboard projects.  The stuff I use is leftover from years ago, when I got it from an old OMC (outboards) dealer.  I have a huge 8 oz. tube of the grease, and  since a little goes a long way, I may never need more.  It's excellent stuff, though, and I'm posting the information here so that anyone interested can try and find a substitute that's currently available.

Replacing the Jumper Stays and Struts

I discovered that at least one of my jumper stays had indeed been damaged when the jumpers were ruined last August--there was a 2-3" section where the wire was abraded.  I decided to replace both wires as a precaution.  Whether or not it is financially the most efficient, I ordered Sta-Lok terminals and wire in order to make the new stays up myself.  The swaged ends are likely less expensive, even when the rigger's labor charges are included, but I want to start shifting to Sta-Loks in the future, and want some more practice with the terminals.

Materials ordered to replace the jumper stays:

  • 41' of 1/8" stainless steel wire, 1x19

  • 2 Sta-Lok fork terminals for the top end, 1/8" size 

  • 2 Sta-Lok turnbuckle studs for the lower ends, 1/8" size with 1/4" threads

I had installed a Norseman terminal two years ago when I built the headstay and roller furler, but that was my only experience with these terminals.  They really are quite easy to install, once you've done one or two.  The basic process is documented below, at least partially.  The two fork terminals arrived first (the studs were on backorder), so I installed the four ends on different days.  The photo documentary below may span both days, since some of the pictures from the first day were out of focus or otherwise unusable.  So, in some of the photos you'll see fork terminals, and in others you'll see stud terminals (designed to thread into turnbuckle bodies). 

One thing I noticed is that the installation procedure is slightly different between Norseman and Sta-Lok terminals.  But the basic process is the same.

Related Link:  Sta-Lok Installation Instructions from the Web

 

Typical Installation Procedure--Stalok Terminals

First, I gathered all the tools needed for the job:
  • Cable cutters to cut the wire cleanly
  • Tape, to wrap around the wire 12" below the end
  • The manufacturer's instructions
  • Knife to help start the untwisting of the wire
  • Wrench for tightening the terminal
  • Loc-Tite (blue) for the threads
  • Polysulfide sealant
staloktools-o.jpg (65114 bytes)
A typical Sta-Lok fork terminal includes these parts (clockwise from left):
  • The main terminal end (body)
  • The wire former (goes inside the female threads of the body)
  • The socket end
  • The wedge
stalokparts-o.jpg (5740 bytes)

A typical Sta-Lok stud terminal includes these parts:

  • The wedge

  • The wire former

  • The socket end (same as in the fork terminals above; not pictured here)

  • The threaded stud terminals

studparts-o.jpg (8396 bytes)

In order to ensure that the new stays ended up the same length as the old ones, I decided to stretch the old (existing) wire out in my garage.  After I had installed the fork terminals on the two ends of the new wire, I was ready to cut it to length so I could install the stud terminals at the lower ends.  Since the Sta-Lok terminals are of different lengths from the original swaged terminal ends, measuring the wire alone would not be sufficient to preserve the overall length.  So, I tied the three forked ends (two on the new wires, one on the old) together and secured them to my garage door, and stretched the three cables out together.

jumpwirestretched-o.jpg (32640 bytes)

With the new and old cables together, and comparing the length of the new studs versus the old, it was easy to visualize exactly where the new cables should be cut to length.  I erred just slightly on the side of cutting the new ones a bit shorter, since I knew that I had had the turnbuckles tightened about halfway in the old setup--so slightly shorter (1/8" or so only) wires would still be plenty long, but I wouldn't have to risk bottoming the studs out if I decided to tighten the stays more than I had previously.  You can see the length difference between the old and new terminals in this photo.

newandoldstud-o.jpg (20990 bytes)

The first step is to cut a clean end on the wire, if one doesn't already exist.  Good cable cutters are crucial for this, though you could theoretically use a hacksaw.  The instructions call for installing some tape about 12' down from the end, just to hold the strands in place if needed.  When the clean end is cut, slide the socked end down over the wire, ensuring that the threads face the cut end of the wire.

stalok1-o.jpg (60399 bytes)

Next, begin to unlay the outer wire strands from the inner core.  A knife is helpful here to get things started, but they unlay easily once you've gotten it going.  Untwist the outer strands down about 2-3" from the end, exposing the central core. 

untwist4-o.jpg (30199 bytes)

Slide the wedge over the core, with the wider end facing the cut end.  Leave about 1/8" of the core showing above the wedge (at least for the 1/8" wire and fittings I used for this job--check the instructions to see if this varies).  

wedgeon1-o.jpg (41734 bytes)

When the wedge is positioned, relay the outer strands around the core and over the wedge, ensuring that they lay in properly and evenly around the wedge.  There's a slot in the wedge, which allows it to compress over the core later in the installation process, and you need to ensure that none of the wire strands fall into this slot now.  The wires wrapped around the wedge makes it look like a snake that swallowed a hamster or something.

stalok3-o.jpg (37411 bytes)

twistedtogether1-o.jpg (35246 bytes)

Slide the socket up as far as it will go beneath the wedge, and install the former inside the female part of the body terminal.  Then, screw the end onto the socket, using a wrench but only tightening with as much force as can be applied with the wrench and holding the end with one hand.  Then, unscrew the end again; this allows inspection of the wire end, to make sure that the wire strands have been properly compressed and formed around the top of the wedge.

wiresretwisted1-o.jpg (35722 bytes)
This shows the wire former inside the female part of the terminal. mtsocketncap-o.jpg (12067 bytes)

Assuming it looks right, continue with the final assembly.  Squirt some Loc-Tite thread locker onto the male threads of the socket, and squeeze a bead of sealant into the female end.   The sealant may be polysulfide or silicone, but if silicone is used, ensure that it is not the type that contains acetates that can adversely affect stainless steel over time.  If the silicone is of the hardware store variety, and/or smells vaguely like vinegar, do not use it here.  It's a safer bet to use polysulfide.

loctiteonthreads-o.jpg (45914 bytes)

caulkincap-o.jpg (19189 bytes)

With the sealant applied and thread locker on the threads, screw the terminal together again.  Sealant should squeeze out the base of the socket onto the wire when properly installed.  Tighten the fitting as described above, and wipe off any excess sealant.

caulkspillout-o.jpg (25008 bytes)

The fitting is now installed, and retains 100% of the strength of the wire alone.  It can be unscrewed in the future for inspection, and all parts of the terminal except the wedge can be reused on a new wire in the future.

 

studnfork-o.jpg (58488 bytes)

The old (left) and new studs on one of the wires.  You can see that the new wire assembly is just a tiny bit shorter than the old, as described above.

oldnnewstuds-o.jpg (18201 bytes)

Several weeks later, I decided it was time to check the fit of my new jumper struts and the new stays, just in case there was a problem.  First, though, I had to reinstall the main spreader bases (see above), so that the lower jumper stay tangs would be in place.  Next, I discovered that the upper tangs (at the masthead) required a new hole for the upper end of the stays, since the Sta-Lok fork terminals were not as deep as the original swaged terminal ends.  There was plenty of metal there, so it was easy enough to drill the new holes a little further down.  With the new holes, and the upper tangs reinstalled at the masthead, I secured the two new stays.

newjumpers42103.JPG (158046 bytes)Next, I fit the new jumpers.  The rigger had left the tubes a bit overlong to ensure that they fit perfectly, so I had to figure out how much to cut off.  Holding the various pieces in place, I determined that about 2" needed to come off each strut, so I made the cuts.  Success!  The new struts now fit perfectly.  I placed the stays in the slots at the end of each adjusting thread and tightened the turnbuckles enough to draw things up.  Everything worked well; there was still plenty of room to tighten the turnbuckles more, which I will do before launch day.  But for now, the main purpose had been satisfied:  my new stays, and the new jumpers, all fit and worked as they were supposed to.

Boom Support Cable

I thought it would be nice to install a boom support cable running from the backstay to the end of the boom when at rest.    I like these because they allow the boom to be tightly and easily positioned at a proper height, both for aesthetics and to better clear the cockpit.  Having the boom tightly positioned reduced wear and tear on its various fittings.

To create the cable, I used a hand swager and readily-available crimping parts.  For the wire, I chose a length of 7x7 stainless steel cable.  I can't install the backstay end till the boat is in the water and rigged, but decided to go ahead and swage a loop and shackle onto the lower end now.  Because this is a low-stress, non-critical component, hand swaging is acceptable; it should never be used for most rigging purposes, however, as it lacks the strength needed.

 

Typical Installation Procedure--Hand Swaging

First, I collected the tools and parts needed.  For my particular loop and shackle, I needed a wire thimble of the proper size (5/32" cable), a length of 5/32", 7x7 stainless steel cable, one 5/32" crimp fitting, and the hand swaging tool.

The hand swager couldn't be simpler:  you install the two bolts on either side of the proper hole in the tool (it accepts four different size fittings), install the crimp fitting inside, properly positioned so that the swage will be close to one end (you do 2 or more crimps for each terminal), and simply tighten the bolts evenly to pull the two halves of the tool together, pressing the fitting tightly onto the wire.

crimpingtools-o.jpg (86390 bytes)
With the fitting positioned in the tool and light pressure on the bolts to hold it, I ran the cable through one side of the fitting.  I slipped a thimble over the end of the shackle I was using, and ran the wire through the eye and over the thimble, then back through the other side of the swage fitting inside the tool.   handswage1-o.jpg (54912 bytes)
Leaving a small amount of the cable protruding through the fitting, I tightened the slack out of the other side of the cable, carefully positioning the thimble and wire as I did so.  Once the slack was out, and things properly positioned, I held things in place and started cranking down the bolts on the tool. handswage2-o.jpg (40974 bytes)
Ensuring that the cables didn't pull our or fall off the thimble, I tightened the two bolts evenly until the swage was complete.  Then, I backed off the bolts, repositioned the fitting inside the tool, and repeated the process, creating a second swaged area on the fitting.  Depending on the length of the fitting, you should have 2, 3, or 4 crimps on each fitting.  The small size of this one prohibited more than two crimps. handswage3-o.jpg (77460 bytes)
This is the finished product. finishedhandswage-o.jpg (72781 bytes)

Once the boat is rigged, I'll complete the installation of the boom support cable by clamping the other end of this cable to the backstay at the appropriate height.  More to come.

Davis Megalight (Anchor Light)

Being stupidly and unnecessarily power-miserly, I never enjoyed leaving the old anchor light on all night long.  It just caused me stress and poor sleep.  Dumb, I know--but sometimes one just has a mental block that one can't get by.  I hoped for a better solution.

I found it in the Davis Megalight, a photosensitive, energy efficient light designed for this use.  OK, OK, supposedly they are not as bright as "real" masthead lights--who really knows, actually--but it's good enough.  Besides, it's better than not showing the light at all, which was my choice much of the time.

Installing the new light was a snap.  It comes with its own bracket and wire lead, so all I had to do was remove the existing lamp from the masthead, snip off the wires, and install the new light in its own bracket, a much slicker arrangement than my original setup anyway.  

Click here to see how I originally installed the old masthead light.

mhlight.JPG (158280 bytes)With the new light bracket installed, I  simply connected the wiring harness to the existing wires in the mast, using heat-shrink connectors.  Then, as before, I wrapped the wire in black electrical tape to keep it neat and less ugly, and secured the wire around the VHF antenna, as before.


Glissando, Pearson  Triton #381
www.triton381.com 

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