Fareastsails Tack Angle

The mast and the boom form an angle at the tack.

Masts are normally raked, (lean aft) about 1 to 1.5 degrees. We normally set the tack angle at 88.5 degrees. This sets the boom to be about parallel to the water line when the sail is not full. As the sail fills with wind, the boom will rise and you do your best to hold it back down with the sheet.

Many sailors have a dodger or Bimini to clear in the cockpit. Sometimes these structures interfere with the boom and thus the end of the boom needs to be higher than normal. In those cases we reduce the tack angle to raise the end of the boom. In such cases the tack angle might become 87 or 86 degrees. If, when the boom is level (parallel to the waterline) it does not clear the cockpit structure, you need to select a reduced tack angle.

A quick check is to make the boom level with the water line (or just use a carpenters level) and when the boom is level, be sure it clears the Dodger or Bimini. If it does, then our normal 88.5 tack angle is good. If it is close or questionable then check the leech length and tell us the Bimini or Dodger is an issue.

If you do select a reduced tack angle, we will then supply the corresponding leech length.

When you have that leech length, pull a tape measure up to the stated luff length. Use a supplemental down haul line to keep the tape in line with the mast. Swing the tape out to the stated leech length, connect it to the clew position on the boom (stated foot length from the mast) and that is where your boom will set.

Alternatively, You may also specify the leech length you wish if you know that number. The Leech measurement is a straight line measurement from the head to the clew and does not follow a curve in the sail (the roach). It is sail edge to sail edge. In that case, we can advise the corresponding tack angle.