Why do I over/under trim?

[Brian D]

Is it me or is it me? Obviously it is me.

Every time I trim I always trim incorrectly. I will change tacks and set the sails, then, if I fall off a wee bit I pick up boat speed. This is telling me what? Am I trimming in too much or not enough? I trim until the mail just stops luffing, and the jib tells are parallel.

Thoughts?

 

[RichH]

You are probably trimming based on the previous tack and havent let the boat fully accelerate to its new full speed out of the new tack, thus are getting fooled by the apparent wind when the boat slows down when maneuvering. In all probability you're trimming for speed when the boat needs a bit of 'power up' to get up to speed. Every time you tack you should (if racing or wanting performance) 'go through all the gears: first, second, high gear' ... not just start each new tack in 'high gear'.

A boat that has 'slowed' (by tacking etc.) will need different/transitory trim for optimal performance than one 'at speed'. If youre sailing to VMG angles, set your trim/angles for the next 'expected tack, etc.' as a slowed boat will have radically different apparent wind (an apparent 'lift' that will diminish as the boat finally accelerates back to full speed).

 

[Don Guillette]

Brian D: Your question sounds very simple but the answer is not.

Here's the problem. There are 8 primary controls for the mainsail and 6 for the jib. All these controls must work together for each sail for a given point of sail and wind condition. Additionally, both sails have to compliment each other or they end up working against each other.

Anytime the wind changes, which it does all the time, or you change direction you have to make an adjustment to the main and jib.

The question becomes, what is the adjustment and how do i know which sail trim control for the main and jib to push or pull. A man could write a book on that subject and in fact I did. It is called The Sail Trim Users Guide.

The first thing you have to know is what are all the sail trim controls FOR THE MAIN AND JIB adjusting. There are only 4 and they are DRAFT DEPTH, DRAFT POSITION, TWIST AND ANGLE OF ATTACK. The next thing you have to know is which controls for the main and jib are used to adjust each of the 4 elements. Once you get to this point you know more about sail trim than 75% of the sailors worldwide.

Next you have to be able to read your telltales and understand what they are telling you. I devote over 7 pages in my book to reading your telltales.

No one wants to take a book on a boat and flip through pages trying to figure out what to do. My solution was to deveop a SAIL TRIM CHART. It is laminated for boat use. The great thing about the chart is that if you follow it a couple of time you'll learn so much about sail trim that you won't need it anymore. Give it to a friend - he'll appreciate it.

 

[Brian D]

Thanks for both anwsers. Don, you charts ARE on my boat. The book is on my shelf at home, with lots of yellow highlites in it. Thanks again.

 

[CharlieCobra]

I had the book and the charts....

can't find either one.

 

[Don Guillette]

Re: I had the book and the charts....

Charlie: Shame, shame but probably you've mastered all the material and maybe you gave them to a friend. If not, dash over to the ships store and re-order!!

My bible is Dennis Conner book "Sail Like A Champion". The book is so beat up that the binding has come loose. Everytime I glance at that book I find something new that I didn't know and I wonder how I missed it the first time around.