90˚ Marked Laser/ILCA Main Sheet - Sailing Chandlery

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April 05, 2024 2 min read

ILCA Calibration Markers By Jack Graham-Troll

Whilst Jack was collecting His New Devoti ILCA we had a great chat about the ways he marks his boat with various calibration marks. Whilst some people would not be as open to sharing this Jack has taken the time to write up why and how to used these calibration marks.

Calibration markings are a valuable tool for optimizing boat setup and speed. Using these markings as a reference, you can note and replicate the optimal control settings for different sailing conditions. This allows you to save precious time when adjusting controls during a race and maximize your boat's speed around each mark and along the racecourse.

Marking Your Main sheet

Understanding your sail angle downwind is crucial for optimal performance. Without mainsheet markings, it can be a challenge to gauge whether your sail is properly trimmed and at the right angle, resulting in your sail being too far out and having a negative impact on speed and control in the boat.

Markings on the main sheet that indicate ninety-degree angles can be incredibly helpful. With clear and accurate marks, you can easily adjust your sail position based on wind conditions. Whether it's light winds or stronger gusts, having the ability to quickly and reliably sheet in or out to maintain the desired sail angle is essential.

Use these markings as a reference to consistently trim your sail angle and achieve maximum speed and confidence downwind !

Just remember when coming a shore and removeing your main sheet to remove the knot at the ratchet block rathe than the boom end block. This will ensure the marking stay in the same place each time you thread the mai sheet on.

How to Mark Your Main Sheet 

1. Rig your boat with the mainsheet threaded through the boom and the mainsheet centre block in the hull.

2. Pull the boom out to position the sail at 90 degrees to the hull.

3. Whilst holding the sail in this position, take any slack out of the mainsheet and mark the mainsheet at both the mainsheet block on the boom and the mainsheet centre block on the deck.

4. To make these marks more permanent, we recommend using whipping twine to mark these positions.

5. When untying and removing your mainsheet, it's important to remember not to untie the knot at the boom end, as if this knot is not retied in the same position, it will alter the distance along your mainsheet to your 90 degree marks and effect your sail angle. We recommend always untying the knots at the mainsheet block and remove the mainsheet through the mainsheet block first and then out of the blocks along the boom and finally from the end of the boom, always leaving the boom end knot tied.

We offers pre-knotted and permanently marked mainsheets for your ILCA dinghy, 

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$10.0

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