Why We Had to Fix Our Mast Rake — and What Happens When You Get It Wrong
Two years ago we replaced Paikea’s front beam with a custom carbon one. The new beam was angled upwards to lift the trampoline higher — better clearance, better performance. What we didn’t fully account for was that raising the beam also raised the forestay attachment point. Which made the forestay effectively too long. Which gave us too much aft rake on the mast.
We’ve been sailing like that ever since. The turnbuckle was maxed out and the boat’s balance was off. With access to a good rigging shop in Sint Maarten, the time had come to sort it out properly.
What Mast Rake Actually Does
Rake is the angle at which the mast leans fore or aft from vertical. It’s set primarily by the forestay length — shorten the forestay and you pull the masthead forward, making the mast more upright. Lengthen it and the mast leans further aft.
Why does that matter? Because moving the mast moves the centre of effort of the sail plan. That centre needs to sit correctly over the centre of lateral resistance — the pivot point of the hulls and appendages underwater. Get that relationship right and the boat sails in balance. Get it wrong and you’re fighting the helm every time you go sailing.
There are two ways to get it wrong.
Too much rake — weather helm. The mast leans too far aft, the centre of effort moves behind the centre of lateral resistance, and the boat wants to constantly turn into the wind. The helm feels heavy. You’re always fighting to stop the boat from rounding up. In strong gusts it gets worse. Shayne has seen client boats where the rake was so far off they couldn’t sheet the mainsail in without the boat violently heading up. That’s not a trim problem, it’s a safety problem.
Too little rake — lee helm. The mast is too upright, the centre of effort sits forward of the centre of lateral resistance, and the boat wants to bear away downwind. This is actually the more dangerous of the two. A boat with weather helm depowers when it rounds up in a gust. A boat with lee helm powers up when it bears away — which can lead to a broach or a loss of control in the wrong conditions.
Paikea had weather helm. Not dangerous, but noticeable, and something that was making every upwind sail harder work than it needed to be.
The Fix
Straightforward in principle: shorten the forestay to pull the masthead forward and reduce the rake.
We pulled the forestay and cut the toggle end off, losing the minimum 250mm needed for the swage. FKG in Sint Maarten re-swaged a new terminal — the same machine shop that had sorted our rudder bearing earlier in the year. Good people to know if you’re working on a boat in that part of the world.
Changing the rake has knock-on effects through the whole rig. A more upright mast means the sidestays need to be longer to maintain the right adjustment range on the turnbuckles — we fabricated new soft shackle strops for that. You also need to check that nothing changes with boom height and headsail sheeting angles, because a mast that moves forward changes clearances and can affect the way the sails set.
None of that is complicated. It’s just the consequence of adjusting one variable in a system where everything is connected.
Why It Matters
Mast rake is one of those settings that sailors either obsess over or ignore completely. The right answer is somewhere in between — it matters a lot, but once it’s set correctly you don’t need to think about it again until something else changes.
For us, something else changed when we put the new front beam on. We knew at the time that the forestay would eventually need shortening. Sint Maarten was the right place to do it — the right facilities, the right contacts, and enough time to do it properly before the next passage.
The boat is balanced now. The helm is lighter, the tracking is better, and sailing upwind is the way it should be.
Gunboat 68 Mast Rake
Mast rake is the angle at which the mast leans fore or aft from a vertical position. It’s the single most important setting for controlling the fore-and-aft position of your entire sail plan.
For the full story of Paikea’s carbon mast — from rescuing a Team New Zealand rig from a Valencia scrapyard through to the finished rotating rig — start here: Paikea’s Carbon Mast: The Full Story
For the engineering detail behind the rig design and the build documentation that doesn’t go in a public video, that’s in the Youngbarnacles members hub.