Boom Brake

[a64pilot]

I’ve had one that came with the boat forever, it’s new and never used.
We had an accidental gybe the other day that could have been real bad, but thankfully the traveller car was overcome exited stage right and nothing got broken other than the car of course, but the boom was completely free In winds gusting to 30 kts and I’d rather not repeat that. I want this to be a one trial learning event.

Anyway I’m pretty sure how to set this thing up, I’m going to use the midship cleats and run the line back to the unused sheet winch to tighten it down. It seems to work well, stays tight with the boom pretty much all the way one way to the other.

However I don’t know how much I should tighten this thing down?
40’ heavy boat 330 sq Ft main.
Should it be so that I can’t physically move the boom by myself, or should it be so that I can just barely move it, or something in between?

[hpeer]

We have a Dutchman. We are 20 tons. I’ve had the Wife gybe repeatedly. F^*+ing scary, especially when I’m up working something. It’s always saved my butt. Wingman leave home without it. I have the line led to a spare winch in the cockpit and I adjust tension with that.

Here is their recommendation.

Dutchmar » Boom Brake

[Mike OReilly]

I’m following b/c while I’ve owned a boom brake for years, I’ve never gotten around to rigging it.

This is the version I have: https://dreamgreen.org/index.php/pro...76-boom-brakes

Similar in concept to the Wichard, but a lot cheaper and made of stainless.

Our rig has a very large and heavy boom. An accidental gybe in even moderate winds would be very bad. This is why we always run preventers whenever the wind is beam or aft. Even on a nice beam reach we’ve got them on, and they’ve saved my bacon more than a few times (probably says something about my sailing skills ).

Still, I would like to rig the brake. My problem is I don’t have good mid-ship cleats. And if I took the lines down to the toe rail I worry about gumming up the side decks.

[a64pilot]

Originally Posted by hpeer

We have a Dutchman. We are 20 tons. I’ve had the Wife gybe repeatedly. F^*+ing scary, especially when I’m up working something. It’s always saved my butt. Wingman leave home without it. I have the line led to a spare winch in the cockpit and I adjust tension with that.

Here is their recommendation.

Dutchmar » Boom Brake

I wonder why they had a winch on both ends of the line?
it would seem that logically you can attach one end to the mid ship cleat and the other around the other clear and then to a winch, it would seem that loosing either side does the same thing, slackens the line?
The line doesn’t run through the brake of course, it’s the tension of the line that provides the friction for the brake to slide over the line.

[JPA Cate]

We have dual preventers rove, and they lead from mid-boom forward to the bottom of the shrouds, and aft to our secondaries. We always use the preventer if sailing deep, and it can be used to downhaul the boom, for sail trim. In our case, we're using 12mm polyester double braid for the line, but for a boom your size, you might be able to use nylon double braid, which is stretchier.

Jim has been running them since his singlehand racing days, and it is really nice to know all your gybes will be controlled. However, you do have to pay attention, and i guess with the Boom Brake, you don't. Horses for courses, I guess.

Ann

[cj88]

Much better and safer to have preventers that run from the end of the boom to the bow. Less chance of a broken boom or a preventer failing due to the loads.

[a64pilot]

Ann, I’m no racer and had in the back of my mind to run preventers, but I’m not sure I have a strong enough attachment point on the boom for that. Sort of the irresistible force Vs immovable object thing, something is going to give.
If I understand the function of the brake, it gives, but does so in a slow enough manner so that nothing breaks, and the rate of give is adjustable,
Plus it came with the boat, why not use something you don’t have to buy.

What we had happen was were were crossing from the Abaco’s to the Exuma’s, started out with a nice wind of about 10 to 15 kts a little aft of abeam, then it began building and slowly clocking from behind us, about the time of our accidental gybe it had built to about 25 to 30 kts indicated and at 140 degrees off our Starboard side, waves got pretty big and we began to surf, something that I have never really had before, we were breaking 11 kts and the AP was handling it fine, then suddenly it didn’t

I won’t usually run deep with the main up. I’ve been going with the Genoa only and I didn’t expect the wind to come from behind us as much as it did, but when the squalls hit I suspect we got a wind shift to go along with those gusts.

[Tayana42]

I also have two preventers set up from about 2/3 of the way aft on the boom to my perforated toe-rails near the chainplates. These make a boom brake unnecessary and also allow for infinitely adjustable downward pull on the boom. They are not run to winches but are multi part block and tackle with a cam cleat on each at the deck end. Not much effort is needed to tension them to just limit the movement of the boom.

[cj88]

Have a read of this if you want to know why an amidships preventer is a bad idea.

https://www.morganscloud.com/2018/10...that-can-kill/

With respect to my comment about a boom breaking with a mid-boom preventer, if you broach badly and the boom drags in the water then the aft half of the boom is not protected from the drag load which can cause the boom to break.

[hpeer]

So on the big boat (44’ and 20 tons center cockpit) we have a Dutchman. At first I led it to the townrails but the Wife complained about the trippin bazaars. So I welded some hard points to the cabin top. One end goes to hard point, then through the 3 blocks in the Dutchman, then to a turning block on the port hard point, then to a cockpit winch. (The boat came with 2-44 winches, located forward in the cockpit. I added 2-53’s further aft accessible from the wheel. This made the 44’s available for the Dutchman-Port and curling-Starboard).

I keep the Dutchman pretty tight most times. I’ll loosen it to move the boom or do an intentional gybe. Then I can ease the main over.

The small boat (33’, 8 tons, aft cockpit) has midship preventers. That run to the toe rail and then back through a 4:1 handy billy to a hard point. It makes a lot of rope hanging around, but i can easily adjust them pretty quickly. Also, it doesn’t have a boom Vang, so this arrangement also does that function.

We owned the small boat first and it didn’t have preventers. When I installed them I realized it took a huge amount of worry off of me, I enjoyed sailing down wind much more. When we got the big boat the Dutchman was an early purchase.

[boom23]

Originally Posted by a64pilot

Ann, I’m no racer and had in the back of my mind to run preventers, but I’m not sure I have a strong enough attachment point on the boom for that. Sort of the irresistible force Vs immovable object thing, something is going to give.

You could use a strong wide strap, which you can have stitched at a sail shop.
It does not have to be permanently mounted on the boom.
Just an idea...

I just found this site, which sells slings pre-made and with more than one ply: Lifting Slings

I would have the block closer to the bow though.

[Jim Cate]

Originally Posted by cj88

Have a read of this if you want to know why an amidships preventer is a bad idea.

https://www.morganscloud.com/2018/10...that-can-kill/

With respect to my comment about a boom breaking with a mid-boom preventer, if you broach badly and the boom drags in the water then the aft half of the boom is not protected from the drag load which can cause the boom to break.

Having run the dreaded mid boom preventers for some 40 years and 150,000 miles now, and on three different boats, I must just be lucky to be alive.

The geometry factors that are shown in the article are not in dispute. However, the actual results just haven't been that bad for us. First, with most modern designs the boom is high enough that getting it in the water is pretty unlikely. Not impossible, I guess, but with the exception of a knockdown when hove to, it just hasn't happened... not even close. I don't think this is a big factor.

Second, all this talk about getting caught "aback" generating huge forces... what we've seen repeatedly is that when sailing deep angles with the preventer rigged the sail may gybe, but with the boom prevented it just gently fills on the other side, and no great forces are generated, and the a/p or wind vane just turns and the sail gybes back. This has happened to us countless times over the years.

We did break the boom on this boat once, when we caught a huge gust coming down off some highlands to windward. This was nearly a 180 degree shift, and from the appearance of the water nearby, must have been 50+ knots. Not pleased, but when we did some forensic investigation, the boom had had a long standing crack that lead to the break. The crack was positioned so as to show that it had been generated by vertical loads generated by overtightening the main sheet against the rigid vang when the boat was at rest. First boat I'd had with such a vang... previously had topping lifts to support the boom when the sail was down. I guess one could consider this event to forever damn the mid boom preventer. We continue to use ours routinely.

Jim

[charliehows]

i made up a wichard ladder style brake out of scrap stainless, been using it for years. Extremely simple. has 3 settings; easypuff; bit tasty; bustyerass - i dont even bother working the sheet for a gybe most of the time, so i recommend taking the trouble to set the thing up if you've got it already. before i made the brake i used to use cheap rope on the carrier, hoping it'd break and take the punch out of a gybe - worked a couple of times but too damn scary and a PITA replacing the rope

[barnakiel]

A climber's eight can be used in place of expensive Wichard gadget.


b.

[brownr377]

Following - I've got a wickard brake that came with the boat. I rigged it up once and had trouble getting the tuning right, it was either too loose and didn't put any brakes on or it was too stiff and didn't let the boom gybe.

I'm quite certain it was operator error, any tips are appreciated.