May 2012 Issue
DIY Trysail Track Retrofit
Considerations when adding a dedicated trysail track.
When I purchased my boat in 2007, it came with a trysail but no separate mast track for it. The sail currently has slugs that fit the main track. I would like to install a separate track for when I go offshore.
I am currently working with sailmaker Carol Hasse (www.porttownsendsails.com) on a new set of primary sails. She is the best at making cruising sails, and it is a luxury I am surrendering to. However, that is why I’m considering a DIY project for the trysail track. Any input on details such as proper track size, length, placement, and preferred mast fasteners and track backing (to combat corrosion) would be helpful.
The mast and boom are Yachtspars (New Zealand), and both appear substantial.
1979 Tayana Vancouver 42
Gig Harbor, Wash.
It is definitely best practice to have a dedicated mast track for a storm trysail, which hoists on the mast but must be capable of flying independent of the boom. Feeder tracks into the mainsail track can work, but having a separate track is preferred.
For your DIY installation, our first suggestion would be to seek advice from your sailmaker. As you’re already a paying customer, we’re sure she would be happy to give her 2 cents for free. In fact, our last trysail article (PS, August 2008) features one of Carol Hasse’s trysails. She uses a basic track for external slides—nothing fancy.
The trysail track is fitted off-center on the aft side of the mast and runs nearly to deck level, so the sail can always be fitted and ready to use. When the trysail is being used, the boom should be secured to the deck. The trysail should be sheeted to the boat’s aft quarters, with blocks mounted port and starboard, allowing the sheets to lead fairly to a winch. Snatch blocks are not the first choice for this job.
According to spar maker Seldén Mast (www.seldenmast.com), the trysail should reach 55 to 65 percent of the foretriangle height, and the track should end about 1.5 feet below any checkstays/runner attachments, if any.
If possible, we’d suggest using the same type of track as your mainsail track, so you don’t need to change the slugs on your sail. If not, Sailing Services’ rigging specialists (www.sailingservices.com) recommend using a 7/8-inch stainless-steel track. When choosing fasteners and track materials, be sure to watch for mixed metals that could cause corrosion. (Example: If you have an alloy mast, don’t use stainless fasteners.) If the track and mast are dissimilar metals, insulation should be placed between them; options include a zinc-chromate primer, Sika’s Sikaflex 292, Boat Life’s Life Calk, or a 20- to 30-mils-thick strip of Teflon or other dielectric plastic.
Along with the track, you’ll need a track gate, a tack attachment, fasteners, and trysail sliders (if you plan to get new ones). To minimize corrosion, use zinc-coated Monel pop rivets for attaching the track to the mast. They are as strong as stainless but less of a corrosion risk; double up on them in high-load areas. Also, it’s a good practice to bed fasteners with a polysulfide compound like Life Calk or Sikaflex.
If you end up replacing your sail’s sliders, be sure to place two or three sliders close together at the sail’s head and tack; this will help spread the high loads that these areas see.