Category Archives: How to

Jib Trim

The following are a set of notes on jib trim.  They have been pulled together with the help of Phil McNeill.  It’s based on what I’ve seen on “Thumper” but should apply just the same to any other Javelin and in general to any boat with a jib and mail sail.

Terms

Woollies – The tell-tales on a sail.
Steering Woollies – The forward/front lower tell-tales used to steer the boat by.

Note the front wooolies on the jib, these are the steering woolies (Ben and Colin in Perth 2015/2016)
Note the front wooolies on the jib, these are the steering woolies (Ben and Colin in Perth 2015/2016)

 

Setup/Trim for the conditions (for pointing)

Light

  1. Sheeting angle 10 degrees
  2. Jib sheet back on clew plate to give the foot some fullness to provide power.
  3. Sheet on until the leech woolly stalls, then ease the sheet a fraction.

Moderate

  1. Sheeting angle 13 degrees for moderate planning conditions (possible 12 to 16knots)
  2. Jib sheet back on clew plate to give the foot some fullness to provide power.
  3. Sheet on until the leech woolly stalls, then ease the sheet a fraction.

Strong – Fresh

  1. Sheeting angle 13 to 16 degrees. Certainly 16 degrees in the fresh stuff.
  2. Jib sheet 1 hole further forward.
  3. Jib sheet eased up to 100mm from the light to moderate air pointing sheet tension.

Boat handling notes

  1. The key is to keep the boat flat and get it balanced so that you have this big steering groove while the boat still wants to climb to windward.
  2. It is imperative that as soon as the boat starts to stagger or not want to accelerate in the puffs, you need main cunningham. This is the power control and you need to work it in puffy conditions.
  3. In the fresh – find the right spot, by starting eased and then tighten up until the boat is hard to keep planning upwind.
  4. In the fresh – we would usually sail with all of the jib luff woollies lifting and we would be driving up to windward on the main. Sheet the main on to point while still keeping the boat dead flat and then easing the main to foot. All with the same jib setting. This allows us ot choose our course and is especially good for making lay lines ie we can choose to sail high or low and fast with our normal jib sheeting position.

Other trim notes

  1. Jib position on the clew plate only really affects the fullness of the bottom of the jib.
  2. The top of the jib is controlled by sheet tension.
  3. Only check the woollies when you are steering exactly right on the steering woollies.
  4. When you are steering to the woollies the top leech woolly must stream.
  5. The leech must always flow otherwise the slot is not working (again subject to steering exactly to the lower steering woollies)
  6. If the top forward woollies don’t flow and the boat is going quick, ignore them. With some of the 470 jibs, if the forward woollies flowed correctly then we were oversheeted and going slow.
  7. Everything in sailing is a compromise.
  8. In theory all the woollies should stream but to achieve that you may have to change to different jibs for different conditions which isn’t practical. Or as has been done – remove the woollies that won’t co-operate!
  9. There should never be creates up the luff of the jib in a breeze
    10. footing – we try to never sail lower than having all of teh steering woollies working.