boom preventers, swept back spreaders,physics junkies

[Jim Seamans]

Setup I used

Was off shore last year and used this setup to settle down the boom, worked wonderfully. No hassle setting up and removing. On a H356

http://www.anything-sailing.com/sho...the-poor-man-s-preventer?highlight=alexventer

 

[RichH]

Rich, do you have a picture or diagram how this is set up?

A figure-8 or rescue-8 simply has the rope/line 'interleaved' through it, the contact area provides the friction and is dependent on how much tension is applied to the 'loose' side.

http://www.youtube.com/watch?v=m9B5XASL3Wc
simple loading: http://www.youtube.com/watch?v=vtZAzzVFDY0&feature=relmfu
and
http://www.youtube.com/watch?v=WMvralRauSE&NR=1 ... for 'heavy loads'.
both show how to 'load' the device ... and in the videos simply ignore the 'tie-off' wrap that is used to 'lock' them during rappelling or rescue so that they DONT slip/move, which would be inappropriate as a boom brake.

The Wichard GybEasy boom brake is very similar to the rescue-8 and is a ladder-friction type device .... http://www.wichard.com/fiche-A|WICHARD|7150-0203030000000000-ME.html shows how one is 'loaded'. A rescue-8 isnt going to control a LARGE AREA mainsail/boom as will the GybEasy .... and there are other manufacturers of such and similar function - slowing down the SPEED of an accidental gybe. Its the speed that causes the magnitude of the IMPACT. Read the Wichard Instructions for the details on set-up, pre-tensioning, and mounting, etc.: http://www.wichard.com/documents/notice_gyb_easy.pdf
Ive found the Wichard device can easily control a mainsail of 400++ sq. ft. with ease, although one should 'soften' (washing and fabric softener) the 'kernmantel' rope that comes with the brake.
Video of usage of the Wichard ... would be the same with fig.-8 and rescue-8: http://www.wichard.com/documents/videoFDBGB.wmv

All of these friction devices in which the amount of friction needed is controlled by the amount of 'pre-tension' you put into them. All of these are derived from devices that have been used in mountain climbing/rescue for many 'decades'; the rescue-8 and figure-8 are still the primary used 'descendera' after about 30 years.


hope this helps.

 

[Bill Roosa]

I've seen a "modified traveler/sheet" setup that also does the trick. He used a recirculation line that started on the boom at a block becket went to a block on the starboard toerail back to the boom block back to the torail (repeat till you get enough purchase) back to the cockpit via several turning blocks and through a cam cleat (where you actually manipulated the line). Then crosses the cockpit (line is loose) to another camcleat on the port side, went forward to a matching set of blocks on the port toerail. This basically makes a multi block tackle that forms a triangle between the toerails and boom. Gives complete control of both tacking and jibing while single handing the boat.
By tightening both tackles you effectively sheet down but not in. By tightening one block you sheet in. By using both at different tensions you can get the boom to do anything you want except cook dinner. It is pretty expensive to set up and get right though.

 

[HukilauMike]

A figure-8 or rescue-8 simply has the rope/line 'interleaved' through it, the contact area provides the friction and is dependent on how much tension is applied to the 'loose' side.

http://www.youtube.com/watch?v=m9B5XASL3Wc
simple loading: http://www.youtube.com/watch?v=vtZAzzVFDY0&feature=relmfu
and
http://www.youtube.com/watch?v=WMvralRauSE&NR=1 ... for 'heavy loads'.
both show how to 'load' the device ... and in the videos simply ignore the 'tie-off' wrap that is used to 'lock' them during rappelling or rescue so that they DONT slip/move, which would be inappropriate as a boom brake.

The Wichard GybEasy boom brake is very similar to the rescue-8 and is a ladder-friction type device .... http://www.wichard.com/fiche-A|WICHARD|7150-0203030000000000-ME.html shows how one is 'loaded'. A rescue-8 isnt going to control a LARGE AREA mainsail/boom as will the GybEasy .... and there are other manufacturers of such and similar function - slowing down the SPEED of an accidental gybe. Its the speed that causes the magnitude of the IMPACT. Read the Wichard Instructions for the details on set-up, pre-tensioning, and mounting, etc.: http://www.wichard.com/documents/notice_gyb_easy.pdf
Ive found the Wichard device can easily control a mainsail of 400++ sq. ft. with ease, although one should 'soften' (washing and fabric softener) the 'kernmantel' rope that comes with the brake.
Video of usage of the Wichard ... would be the same with fig.-8 and rescue-8: http://www.wichard.com/documents/videoFDBGB.wmv

All of these friction devices in which the amount of friction needed is controlled by the amount of 'pre-tension' you put into them. All of these are derived from devices that have been used in mountain climbing/rescue for many 'decades'; the rescue-8 and figure-8 are still the primary used 'descendera' after about 30 years.


hope this helps.

It sure does help. Thanks.

 

[Cayennita]

Ask T-10 racers how many booms they have broken because they failed to ease the boom as they go around the weather mark to a broad reach or run. Racers normally have one person dedicated to the vang. If a broach is going to happen, that's the second item released after the main sheet, then the spinnaker. You recover in reverse. Trim chute first, then vang and main sheet last.

 

[Gunni]

I am completely happy, and more important, sleep well off-watch with a Wichard GybEasy. Elegant, simple solution. After long study, and some hair-raising, boat-damaging accidental gybe situations (with preventer cleated off) I settled on this out-of-the-box solution. An easy install too. There are other solutions, but anything that locks the boom on a cruising boat is just one inattentive/inexperienced helmsman away from heartbreak. KISS baby!