The mystery behind a sinking mast

When owning an older yacht, you’ve got to be prepared for unexpected problems that go beyond regular maintenance and upkeep. So when I noticed the shrouds and stays on my 24ft Seafarer Mikula slowly losing their tension over the season I suspected something was amiss.

I mark the turnbuckle screws so I can quickly get them to almost the right tension each spring, and then use my rigging tension gauge to fine-tune the whole rig. Our sailing season here in Quebec lasts around six months at best, and each autumn I take down my mast before covering the boat for the winter.

While I don’t belong to the racing crowd I do, nevertheless, try to get the best performance out of my boat. Part of this comes from checking the rig tension from time to time – visually (for example, by surveying leeward shrouds when sailing in strong winds) and with my Loos & Co gauge, which I use to check each shroud and stay. It bothered me that I was having to re-tune my rig before the end of the season, but couldn’t figure out the cause.

I couldn’t detect any visible deformation on the boat hull, deck or cabin, and all chainplates looked perfect, no leaks around them or lose bolts. The Seafarer 24 is a solidly built boat; the mast is deck-stepped and the mast load is transferred to the keel box ⁄16in there should be more than enough strength to withstand the loads imposed on them. displaces only 1,815kg (4,000lb) and with her 24m (260ft) sail area (main sail and working jib) she is definitely not over-canvassed.