How do I adjust the mast rake and rig tension on a Malö 36?
I've just bought a 1999 Malö 36 and the rig feels a bit slack. She has a Seldén mast with double spreaders. How much mast rake should she have, and what is the proper sequence for tensioning the cap shrouds and lowers?
Answer
Adjusting the mast rake on a Malö 36 starts with setting the forestay length to achieve a 1 to 2 degree aft lean, followed by tuning the cap shrouds to 15 to 20 percent of the wire breaking load. Because these boats typically carry a deck stepped Seldén masthead rig with 8mm or 10mm stainless wire, you must use a proper tension gauge or the Seldén folding rule method to balance the lowers and keep the spar perfectly straight under load.
Setting the Mast Rake
The Malö 36 is a heavy displacement cruiser that needs a slight weather helm to maintain feel on the wheel and point well upwind. You achieve this by raking the mast aft. A rake of 1 to 2 degrees is standard for this hull.
Check the compression post down in the saloon for any signs of settling before you begin tuning. To measure the rake, ensure the boat is floating level on her lines. Hang a heavy weight, such as a large spanner, from the main halyard to act as a plumb bob. On the typical 15 metre Seldén extrusion fitted to these boats, the halyard should hang 150mm to 200mm aft of the mast track at boom height. If the rake is off, slacken the backstay completely and adjust the forestay rigging screw. Shortening the forestay brings the mast forward. Lengthening it rakes it aft.
Centring the Cap Shrouds
Once your rake is set, centre the mast athwartships. Take the main halyard down to the port toe rail, mark the tension, and swing it over to the exact same spot on the starboard toe rail. Adjust the cap shrouds until the mast is perfectly central.
Before cranking on the rigging screws, clean the threads and apply a dedicated rigging grease like Seldén rigging oil. This prevents the stainless threads from galling and seizing under heavy load. To set the tension:
- Hand tighten the cap shrouds equally on both sides.
- Use a Loos PT3 gauge to measure the tension on the 1x19 wire.
- Target 15 percent of the breaking load for a standard cruising setup, or up to 20 percent for heavy weather sailing.
- Alternatively, use the Seldén folding rule method. Tape a two metre folding rule to the wire. Every 1mm of stretch over a two metre span equals 5 percent of the breaking load. Tighten symmetrically until a 3mm to 4mm gap opens at the bottom of the rule.