Boom Brake
Don’t leave the dock without it! Eliminate uncontrolled gybes, broken booms, gears, heads and bank accounts.
WHAT IS A BOOM BRAKE?
The device controls the upward and sideward motion of the boom. It consists of a brake drum - a solid cylinder machined with helicoidal grooves. The grooves provide more friction and tend to prevent over ride and jamming. The brake drum is fixed and fitted between two cheek plates which is allowed to swing when fixed under the boom. A control line wound around the drum dampens the swing. The line is fed through two bottom attached swivel guide plates and led down to the deck fastened on both sides of the vessel. One side is lead aft to the cockpit winch or other tensioning device.
HOW DOES IT WORK
The brake simply works by using the friction provided by the force of wind on the sail. More wind, more friction, more braking effects. Wind energy is converted to friction provided by the line wrapped around the brake. Friction and holding power can be easily adjusted accordingly by easing or increasing line tension, changing drum wraps and /or line sizes. The line holds the boom in check so no more uncontrolled gybes, no more broken booms and more importantly, no more worry about personal accidents
INSTALLATION HINTS
The brake should be fitted ¼ to ⅓ under the boom and aft of the mast.
Methods to fasten could include a dedicated boom vang under boom slotted captive fitting or a complete wrap around the boom. Select the best for your particular installation. In any event, it will be just aft of a broom brake or down haul if already installed. The aft chain plates are best suited to fasten the deck fittings but always fasten under the rigging. Drill an extra hole just for this purpose.
The aluminium toerail may be is selected but the loading on the brake is substantial so beware of possible bending and distortion. If using other through deck fittings. Always use a good backing piece to spread the load. Also, always use a good turning block at the deck level. If in doubt, use the larger size brake with heavier rope.
Before deciding on boom attachment, and only after the deck positions are selected, swing the boom through a complete arc, fit the brake just aft of this ark—up to 12 inches is okay.
After completing the installation, swing the boom from side to side to ensure the line moves smoothly over the brake and runs freely through the deck turning sheaves. Tighten the control line from the cockpit (winch or other tensioning device) to ensure the brake is working.
SAILING WITH YOUR FLEMING BOOM BRAKE
Sailing to windward, the main sail will be well controlled “tensioned down’’ by the main sheet so the line on the boom brake should be slack.
Coming off the wind when the main sheet is eased, the sail will tend to lift, so tension in the brake line will increase and will need adjustment. Sailing further off wind, more line tension is required to prevent the boom lifting further. Should the sail back wind and the boom gybes, the brake line tension will slow the movement until the boom gets to the point off spilling the wind. If the sail does not move completely over, ease the brake line or momentarily increase main sheet tension.