Calibrate Your Speed Controls
by David Dellenbaugh

Remember how fast you were going upwind at the end of your last regatta? You felt like the boat was finally in the groove, and you actually had a pointing and speed edge on your competition!

Unfortunately, that was almost a month ago. Now, as you prepare your boat for the next big race, you can’t remember how the rig was set up. You have no idea how much pre-bend or rig tension you carried. And your new jib trimmer wants to know what halyard tension and lead position worked best before.

A. Cunningham tension
A number scale works well here, either on the mast near the tack of the sail (use a mark on the sail or the Cunningham grommet) or near a mark on the Cunningham control line.

One of the keys for success in sailing is the ability to reproduce the way your boat was set up when you were going fast. This is especially true for upwind performance, where small adjustments can make huge differences.

It’s not too hard to get your boat going fast occasionally. This may be a matter of luck, but sooner or later almost everyone gets their boat set up exactly right for the conditions, even if it’s just for a few moments. That’s a great feeling!

However, if you want to be fast consistently over time, you need more than good fortune. You need a systematic approach to tuning and trimming all your speed-related variables. This is where calibrating, coding and measuring is important.

B. Helm reference marks
If you have a wheel, put a reference mark at the top when it is centered. Then add marks on each side when the rudder is turned 2°, 4°, 6° and 8° (you can’t do this with a tiller).

The key to good performance is simple: Identify how your boat is set up when it’s going fast, and be able to reproduce this the next time you have similar conditions. This won’t always work, but it will get you in the right ballpark, and it will get you there quickly so you don’t waste a lot of time (and speed) re-learning what you knew before.

C. Halyard position
Place a number scale on the mast next to the loaded halyard. For wire halyard, use a piece of seizing wire as a reference mark; for rope halyards, use a magic marker. Invert the scale shown here so higher numbers mean more halyard tension.

Tips about calibrating

• When you use number scales for measuring, orient these so the higher numbers mean that the control is being pulled tighter.

• Position all reference marks and scales so that you can see them, if possible, from your normal sailing positions. You may want to place two sets of numbers near some controls - one for each tack.

• Look for ‘sweet spots’ or ‘happy moments’ when the boat is ‘dialed in’ (i.e. it feels great and your performance is better than nearby boats). Note the settings for key variables at these times.

• Unless you have an extremely good memory, record fast settings in a notebook after each regatta or day of sailing. List the conditions (wind and waves) and any specific settings that seemed to be fast.

• For clarity, use numbers or colors when you ask team members to make adjustments. For example, it’s not so clear what you mean if you say, “Give me more outhaul.” It’s much clearer to say, “Tighten the outhaul to #5.” or “Pull the vang to Red.”

• Your reference marks may not be 100% reliable or comparable over time since tuning variables can change. For example, shrouds, halyards and steering cables may stretch. So either re-calibrate these after a while, or use your marks to help you measure how much they are changing.

D. Headsail trim marks
Put clear marks on your lower spreaders at regular intervals from the end. Use these to reproduce jib lead position and jib sheet trim on each tack, and to compare setting on both tacks.

Measure theses 15 speed-producing variables

One of the keys to good upwind speed and pointing is being able to get all the right rig and sail settings consistently. To do this, you need calibration scales on all your main speed-related controls so you can reproduce fast trim.

Use a number scale for measuring the luff tension in your mainsail (see A below).

Put a number scale on the end of the boom near the mainsail clew to measure the fullness in the lower part of your main.

Vang tension
Use colored marks on different parts of the vang for reference. Then you can say, “Take the vang to yellow!”

E. Mast position at partners
Put a reference mark on the mast and one on the deck where the mast is at its ‘neutral’ (middle of its range) position. You could also use a number scale here, or just count the number of blocks that you put in front of or behind the mast.

Mast butt position
Calibrate the fore-and-aft position of the mast step using a system that works with your mast.

Mast partner position
See E (below) for several ways to identify exactly where the mast is at deck level.

Jib/Genoa halyard
Measure halyard tension with a number scale on the mast and a reference mark on the halyard (see C).

Rig tension
Use a tension gauge on the shrouds, or measure how much jack pressure you use to pump up the rig.

F. Backstay tension
This measuring device can be as simple as a ruler taped (or fixed more permanently) alongside a reference mark (tape, seizing wire or connector) on the lower backstay.

Backstay tension
Use a number scale and a reference mark on the backstay to gauge tension (see F).

Jib lead position
Use a numbering system to identify both the fore-and-aft and the athwartships position of the jib car.

Jib trim angle
Put calibrated marks (numbers or colors) near the spreader tips to see relative position of the jib leech (see D).

Rudder angle
Put marks on your wheel (see B) that correspond to different rudder angles so you know how much helm you have.

Fore-and-aft boat trim
Place an inclinometer along the fore-and-aft axis of the boat to measure weight placement.

Angle of heel
At the forward end of the cockpit, put an inclinometer perpendicular to the boat’s centerline to measure heel angle

Mainsail and jib sheets
Put marks on each sheet in a place that’s easy to see; use these for reference when trimming.

Traveler car position
Use a number scale along the traveler track to quantify the position of the traveler car on each tack

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