As promised:
https://picasaweb.google.com/wfhogan...eat=directlink
The vang-brake is simply a Black Diamond brand aluminum figure 8 that mountain climbers use for rappelling. It is similar to the Winchard "Gyb'easy", except its smaller, lighter, uses the same attachment point as your present vang, and costs oh, about 20 times less than the other product.
(of course you don't get that cute Winchard logo, or the cleverly named "Gyb'Flex" line to rig it with)
I integrated it with my boom vang with the brake as a result of a flash of insight while I was rigging it:
" Ooooo look how cool it.....DAMMIT!!! Now I have to buy and install another bail on the boom for the vang...No, WAIT! - if I simply clip the vang to the....."
(Being a cheap lazy bastard has its advantages)
Then I scrounged up a couple of 1/4" harken micro blocks I had lying around, and u-bolted them to the forward spreader stay chainplates.
I rigged 30 feet of 3/16" 3 strand nylon line through everything (next time, I'll use 40 feet). and back to a couple of Hershoff cleats I already have on the combings for preveters and such.
The nylon line is cheap, stretchy and abrasion resistant. 3 strand rope seems to have more friction for a given tension than braided, but I'm not positive about that.
Stretchiness is good because it acts as a shock absorber for the dynamic loads of the boom as it stops.
The key to its effectiveness is proper tension on the brake line. Too little, and it does nothing. Too much, and it locks the boom in place acting as a preventer.
Somewhere in the middle is a range of tension that will allow slow, graceful jibes.
The system has a huge safety advantage over a traditional preveter in that it prevents broaches to leeward (the most dangerous type) along with crash gybing. Once enough wind gets behind the main it will come about no matter how much tension you put into the device, but it will come about SLOWLY. This is not the case with a regular preventer. In a leeward broach you have to either cut the line, free it, or wait for it to part, or the boat will stay pinned down by the backwinded main.
This can quickly sink a boat via down flooding through the companionway.
You don't have to switch it in the middle of a gybe either - it is self tending.
I currently use my sheet winch to tension the line, but that's a hassle. I'm going to try rigging a tackle next. If that works, I will no longer need the cleat, and can use padeyes, and permanently rig it to them. Then I'll mark the tail of the tackle at the appropriate tensions I arrive at so its easy to repeat.
Having the vang attached to the underside of the figure 8 works great. They complement each other by pulling from different angles.
Rig one up and play with it. You will be amazed at the difference it makes for controlled downwind sailing.
=)
Belay Devices:
http://tinyurl.com/4nqdbat
Micro Blocks:
http://tinyurl.com/4vyjy9j
3 Strand Nylon Rope:
http://tinyurl.com/49z6uvz
Cheap, eh?
