Basic Sail Trim

with Koralina

trimThere is an abundance of books out there written about this single topic: Sail Trim. I often asked myself “how can I ever master such a complex skill?” Every time I go sailing I learn a little more about sail trim which leads me to believe mastery is over-rated, and learning is continuous. None-the-less I have learned a plethora of tips, tricks, and acronyms, over the years, to keep it all straight.

What the most basic way to understand sail trim?

The most common phrase related to sail trim is simply: “When in doubt, let it out”
In my experience it’s a great place to start; however I’ve altered this long time saying to read
“When in doubt, let it out- If it’s luffing, it must come in”


So what’s it really mean and how can I use it to refine my sail trim?

It’s easier to explain and understand if we break it down into two parts
Main trim and Jib trim

  • Main trim:

    “When in doubt, let it out- If it’s luffing, it must come in” works excellent here. As we get more advanced we learn that when we go up wind keeping the boom running along the center line of the boat will give us the greatest amount of lift towards the wind. Next week we’re talking about sail controls and will go over how to get your boom in the center).
    As we head down off the wind we want to keep easing the sail to the brink of luffing as we turn. You can make sure you have the appropriate trim by easing your mainsheet and few inches and seeing if your sail luffs. If it does then pull it back in and you know you have the right trim. If it does not luff then you know it’s over trimmed and needs to be eased out some more. Generally speaking at the run/broad reach angle we want the sail just off the shrouds. This technique will prolong the life of your sail by not creating a “wear spot”.


Are there any good tricks for remembering proper jib trim?

Yes! Using the tell-tales is the easiest way to get perfect jib trim every time. The tell-tales are your “tell tale” symbols on your jib to help you refine its trim when sailing on a beam reach or above. Usually they are pieces of yarn colored red and green on either side of your jib (but not always I’ve seen blue instead of green).

  • Jib trim:

    “Outside tell-tale, let it out- Inside tell-tale, pull it in” The basic idea here is you want to trim or ease the sail to the “tattling tell-tale”. If your thinking “Huh?” Let me explain:
    If you’re sailing on the port tack (wind is coming over your port side, the sails are on the starboard side) the outside tell-tale is the one on the starboard side of the sail, closer to the outside of the boat. The inside tell-tale is the one on the port side of the sail, more inboard. The term tattling refers to the tell-tales tendency to wiggle, or sway uncontrollably.
    So if your sailing along on the outside tell-tale is tattling you would want ease the sail out toward that outside tell-tale.
    Thus I like the saying: “Outside tell-tale, let it out- Inside tell-tale, pull it in”

This is great if I’m changing direction, what if I want to steer my boat to where my sails are set so I don’t have to change them?

This one is probably the simplest of them all. So you’ve picked your direction and set your sails (using the tips above to help) and now you want to sit back and drive your boat to that trim. It’s easy and only takes small adjustment of your wheel or tiller to keep your boat cruising forward.

  • Tiller driven boats: “Tiller towards the tattling tell-tale” This means if your starboard tell-tale is wiggling around push/pull your tiller to starboard side until that tell-tale settles down and streams aft (towards the back of your boat).
  • Wheel driven boats:  If the port tell-tale is wiggling uncontrollably you want to steer your board away from that tell-tale until it streams aft. In this case, you’d want to steer your boat more to starboard to get your port tell-tale streaming aft.

Looking for more?  Consider taking one of our Sail Trim and Balance Seminars.