Mast Rake

Step 1 - A Solid Base

Before you get into fine tuning the rig your mast step must be in good condition with ZERO movement. If the step has any twist at all this must be remedied. It's also the perfect opportunity to make sure the mast is actually in the right spot. To check this, measure from the stem (FMP in the class rules) to the front of the mast step. The class rules (D.9.2) state this measurement should be between 1210mm and 1230mm. Try to get yours to 1210mm.

Step 2 - Centre the Mast

Use the main halyard to measure the mast tip is straight side to side. Pull halyard to aft port corner with slight pressure and mark halyard where it meets the deck, pull to the opposite corner using the same pressure, the mark should meet the deck as before. This will confirm the mast is central. Note the Super Spars M6 is very flexible, be sure not to pull the halyard too hard or the mast will deflect. You only need enough pressure so the halyard is just about taut. Tying a small bottle of water to the halyard is a good way to confirm equal and consistent pressure between sides.

Step 3 - Rake

Apply rig tension, check the mast is still straight laterally. Shrouds may need adjusting.

Attach a tape measure to your main halyard, pull to the top of the mast and measure 5816mm (19’1”) to the top edge of your lower black band. Once you have this, take your tape to the transom. Get a friend to hold a rope between the top corners of the transom so it creates a taut, straight reference line you can measure your rake against. Read the tape where it meets this refrence line. This is your mast rake measurement.

Adjust your chainplates up or down until the measurment is at 6910mm (22'10") with rig tension applied. 

Remember to use consitent pressure but not so much that you accidentally pull the mast tip aft.

Step 4 - Test

You've a good starting point now and an average rake setting. It's not for all boats as there can be varience in the centreboard bolts or underwater profile of the hull so you may need some fine tuning. Go out for a sail in medium wind conditions. With the boat flat there should be no weather or leeward helm. To test it just loosen your grip on the tiller extention, the boat should continue in a straight line and not want to point up or bear away.

If the boat wants to point up you need to push the mast slightly forward and vice versa if it wants to bear away. Remember the boat MUST be flat when testing as any heal will induce weather helm.

As the wind range increases you can slowly drop the mast back to rebalance the helm.

Keep in mind you will need to keep releasing and applying tension while adjusting the chainplates, doing a lot of back and forth through this. Try to replicate the tension each time as it can alter results. Buy a good tension gauge, Spinlock or Loos PT1 (and some patience if you can find it in stock anywhere) and it will go a long way toward repeatability.