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ボート用品 Dutchman BB250のPDF オーナーズマニュアルをオンラインで閲覧またはダウンロードできます。Dutchman BB250 12 ページ。 Boom brake

Check Line Tension

Set the boom height to the lowest normal sailing position and snug up the

vang. Locate the boom on the centerline. Temporarily run a line through a

block or a shackle temporarily secured to the boom attachment point. Tie or

tape the block or shackle to the boom if needed. Then run the line down to the

potential deck attachment points. Snug up the line and secure it with tape to

the deck if needed.

Now swing the boom out, and observe the tension on the line. The line tension

should not change significantly as the boom swings through it's arc. If the

tension does not change more than 1 to 2 inches, you will be able to jibe

without touching the main sheet, as the tension on the line will be constant. As

a rough guide, the tension should not change more than 4" for the 250 series,

6" for the 500 series, and 9" for the 750 series. The line should become

tighter as the boom moves towards the centerline.

In general, by moving the boom attachment point back or the deck attachment

point outboards, you will make the line tighter as it approaches the centerline.

It may take a few try's to find the best combination.

You may find that, if you have any kind of a cabinhouse, the Brake

will rub against it or the handrails at some point. This is often unavoidable.

Bear in mind that the Brake slides along the line and the line itself does not

move significantly. The line will not cause significant chafe, depending on the

angle and contact material. Install stainless steel or bronze chafe strips along

the contact area if needed, particularly if the line is rubbing against a teak

handrail. Once you have determined the best mounting locations for the boom

and deck attachment points, move on to the next section.

It is essential to follow the load recommendations given in the specifications

section. You must ascertain the safe working load of any piece of

hardware that you install or use. The failure of any part connecting or

tensioning the brake line could have dire consequences.

If you will be tensioning the brake by a line running to the cockpit from the

mast, both ends of the brake line will be secured at the deck attachment point.

You will not need to mount a turning block.

Chainplates We like using the chainplates, since it's one attachment point you

can be pretty sure of, and it's exactly where the line should run to on most boats. Never attach the brake line to anything

higher than the lower toggle, and never attach anything so that it can pull apart a toggle or turnbuckle. File or sand off

any sharp edges where the line will touch. We normally secure one end of the line to the chainplate by wrapping it

around the chainplate or lowest toggle at least 3 times. One pass must go though the lower toggle, to keep the line from

sliding up on the toggle or turnbuckle. Tie off the line using a splice or, temporarily, a bowline.

If you use the chainplates, you must test the chainplate for movement under load after mounting the brake. Chainplates

which are thin strips of metal will bend and fatigue from any side load.

Temporarily run line

Swing boom out, check line tension

Line attached to toggle

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