setting the hook with larger boats

Bad Obsession · Feb 24, 2009

My suggestion is for you to set your anchor the way that it works for you. If you have experience setting it one way and you haven't drug yet, then go for it. There is no such thing as an anchor that sets perfectly everytime and eventually we all will drag at some point in time.

Maine Sail · Feb 24, 2009

NA..

newly anonymous said:
(I'm starting a new thread here so as not to hijack another discussion.)

My friend Maine Sail has repeatedly voiced the assertion that the prudent boater should always set the hook by backing down at 80% of wide-open throttle. Now on my boat, with a 75-horse turbo diesel (Yanmar 4JH3TE) and a three-blade prop (Flex-O-Fold), that's a lot of power. A LOT of power.

Even with an all-chain rode, I can straighten the rode out bar taut at about 1,500 RPMs, which is only 42% WOT. At 80% WOT in reverse, I'm going to start smoking the packing gland, I'm going to seriously stress the windlass clutch, and I'm going to bury that Rocna into more than a fathom of mud.

So my question here, directed to boaters with engines my size and larger, is how much power you actually use to set the hook. Is it different for larger boats with more powerful engines?

I think there is a point of diminishing returns but the bigger the boat the bigger the hook. Straightening the chain can occur at relatively LOW wind speed so please do not judge setting your hook on that.

On our boat, with a 44hp diesel and fixed three blade prop at 80% WOT, she is pulling about 500lbs of thrust in reverse. Remember a 35 pound Rocna held 5000 pounds multiple times in the Sail mag tests so you are not stressing the hook at all. Plus I am assuming you have a a considerably larger anchor than a 35 pounder.

As for stressing the windlass clutch you should NOT be using the windlass to anchor the boat. She should be snubbed to a bow cleat! By this spring I will have a 5000 lb digital strain gauge and will do some of the first "real world" testing ever done on pendant strain and anchor loads at given wind speeds (can't believe I need to spend 1k clams to do this and the mags and "real" authors have done squat!). I will also test validity of the Michigan Wheel thrust calculator to see how close my 500 lbs is at 80% to reality.

If you are snubbed to the bow cleat and your anchor is properly sized I still can't imagine you seeing much more than 800-900lbs of thrust. If you are dragging at even 50% of WOT I would have cause for concern.

I have been backing down this way for years and years and the one thing I learned is that if my boats engine can drag the anchor it is not properly set. I also have backed down with bigger motors and hooks than yours using the 80% method and when properly set could not budge the hook..

The bigger the boat, the bigger the engine, the bigger the hook & the bigger the windage so all is fairly relative...

Please also remember this is 80% from a static position with the rode already snug NOT a running start. It is similar to pulling a water skier out of the water. The steady pull will slowly and steadily bury the anchor into the bottom. If you start with a slack rode or ski line you'll yank the anchor out of it's initial set or the arms off the skier..

Like anything this is my personal opinion but one I have found through both diving and experience to never yet let me down and there have been plenty of opportunities. While I love my Rocna I DO NOT for one second believe it, or any anchor, is a 100% self setter..

Ross · Feb 24, 2009

Re: NA..

When Phil's avatar drops the hook do they back down to set it?

Don S/V ILLusion · Feb 24, 2009

newly anonymous said:
... an Iowa-class battleship is proportionately less powerful than my boat.

Iowa class delivers 212,000 horsepower (all four shafts) to power 51,271 tons full displacement. My boat delivers 75 horsepower (single screw) to power 15 tons full displacement. Do the math, and you'll discover that my horsepower/displacement ratio is higher than the battleship.

Now, if I might restate the question, how much power do owners of boats with 75 horses or more use to set the hook?

I think it's torque and not HP that is the true measure but you may be correct regardless. My supposition is that this is in large measure a "feel good" test as most sailors likely don't precisely measure their % of full power when backing down.

I understand your curiosity but, no matter what anyone does, a prudent sailor should still make an anchor watch if the weather deteriorates. Would backing down at 80% power make you sleep better than 70% or not as well as if you backed at 90%?

Ross · Feb 24, 2009

Re: believe it or not, Ross...

Just did the math. There is no way that your prop is absorbing 75 hp in reverse.

Benny · Feb 24, 2009

You have to take into consideration the size and type of the anchor and the composition of the bottom. Setting a larger anchor usually requires more pull than a smaller one. Anchors are sized according to boat displacement and usual anchoring conditions and there is no set percentage of power to be applied as equipment and conditions vary widely. I for one utilize three separate pulls to set the anchor instead of one big powerful pull. I find it actually easier on the engine to set the hook in a stiff brezze as the windage works in your favor. I have learned not to use the word "always" in connection to anything having to do with boating as more often than not I have been proved wrong. Just continue doing what works for you. I have also found that if you carry a big enough anchor you don't need to be as good anchoring.

Stu Jackson · Feb 24, 2009

It REALLY doesn't matter

what we suggest.

If I had his boat, I'd do what I do on my boat, make damn sure the hook is set, based on the best advice I could get from people I trust, never knowing what wind could come up during the night.

I would make sure MY boat was snug. Now, how ya do that is up to each individual skipper.

I'd rather be downwind of Maine Sail than Mr. I-don't-wanna-stress-it.

Ya'all might wanna take a peek at Reply #22, here: http://forums.catalina.sailboatowners.com/showthread.php?p=603486#post603486

Your boat, your choice.

Hermit Scott · Feb 24, 2009

Didn't want to start a whle new thread for my question, but how do sailboats set the hook that don't have an engine? Also since I have a small motor should I just give it all it has for a 5 second count to get the hook set in as good as possible?

Stu Jackson · Feb 24, 2009

Hermit, they BACK their sails

and get the most sternway they can.

Follow Maine Sail's advice with whatever engine ya got!

Scott B · Feb 25, 2009

Maine Sail said:
She should be snubbed to a bow cleat!

Do you have a picture of this. I have a cleat in the anchor locker, but is on the opposite side of the jib furler, meaning I would have to take the anchor line from over the bow and back into the anchor locker.

Maine Sail said:
While I love my Rocna I DO NOT for one second believe it, or any anchor, is a 100% self setter..

I'm a believer!! After a barely backed down set, 3.7:1 rode, 10 knots wind increase to 52 knot gusts after a 110 deg. shift, and didn't budge on a 35 lbs. Rocna.

However, I've made sure since, I back down hard on EVERY set.

Franklin · Feb 25, 2009

Yes, you have a much larger engine then most of us, but you also have a much heavier boat with much more wind resistance. When the wind blows, you pull a lot harder on your anchor then we do and so you need a much larger anchor. So to set it, you need to pull harder. So the 80% rule is good for you too.

Back when I used my danforth, I used to back it down 80% and sometimes more. One of the tests I did with my Bulwagga when I first got it was dropped it in 25 knots of wind and then backed it down with 90% reverse and it didn't budge so I was confident it could handle most conditions. I should have kept backing her down

Maine Sail · Feb 25, 2009

Scott B said:
Do you have a picture of this. I have a cleat in the anchor locker, but is on the opposite side of the jib furler, meaning I would have to take the anchor line from over the bow and back into the anchor locker.

Holy crap that is "cost cutting" to the extreme!

No bow cleats and no bow chocks! Why would any builder do that?? What happens when you go beam to in a storm and do this??

Stu Jackson · Feb 25, 2009

Scott B said:
Do you have a picture of this. I have a cleat in the anchor locker, but is on the opposite side of the jib furler, meaning I would have to take the anchor line from over the bow and back into the anchor locker.

Scott, just take the furler line down the OTHER side of the boat.

It could be that the cleats are further aft than shown in the picture. I do remember "some" builders put their bow cleats so far aft you can use them for midship spring lines!:dance:

Bob S · Feb 25, 2009

Mainsail,

I have a similar set up. I do have two cleats but no chocks. I thought of putting them in.

Scott B · Feb 25, 2009

Maine Sail said:
Holy crap that is "cost cutting" to the extreme! No bow cleats and no bow chocks! Why would any builder do that?? What happens when you go beam to in a storm and do this??

They're not built THAT cheap !!!

Bow cleats are just at the base of the bow pulpit. No chocks.

Stu, what I meant was the forestay is attached to the top of the anchor roller. To get the rode out of the anchor roller, it would have to go forward and around the forestay. If I use the bow cleat, starboard, it would rub against the side of the boat.

Just trying to learn something new here.

Stu Jackson · Feb 25, 2009

Scott, Not sure I understand: "Stu, what I meant was the forestay is attached to the top of the anchor roller. To get the rode out of the anchor roller, it would have to go forward and around the forestay. If I use the bow cleat, starboard, it would rub against the side of the boat.

I don't understand what you're trying to do. Regardless of whether the forestay is connected to the anchor roller or to a stemhead fitting, all of us have forestays that bisect the bow, so one anchor is on one side, and another on the other. In your case, the anchor roller itself is to starboard, so why not use the starboard cleat? What rubs against the boat? The anchor rode goes out through the anchor roller and then back to the cleat. The rode shouldn't go from the cleat over the side of the boat to the anchor, it's gotta go through the roller.

Scott B · Feb 25, 2009

Maybe I'm misunderstanding Maine Sail. He has said not to run the rode through the anchor roller. I was trying to picture how to get the rode off the roller.

I have a cleat in the anchor locker that I use, which is just behind the "hump" in the lid to the locker.

Guest · Feb 25, 2009

Anchoring

Our 1991 Passage 42 while cruising weighs in at about 30,000 pounds. I've solo anchored hundreds of times in all types of weather conditions using a 40 pound Danforth anchor, 50 feet of chain, a 20 pound lead kellet and 250 feet of rope. The one time the anchor did not hold was in Cortez Bay on Cortex Island, notorious for poor holding; thin layer of mud over shale. The Danforth would not bite into the shale so the gale force winds moved our boat about 100 feet during the night, but no harm done.

The following procedure works for me:

1. Drop anchor with adequate scope.
2. Secure rope to bow cleat.
3. Slowly (idle) back down until anchor sets.
4. Increase to 1,800 RPM to confirm set.
5. Shut down boat and attach kellet to rope rode.
6. Kellet slides down rope to chain shackle.

As long as the above process works for our boat I'll continue to rely on it. When strong winds role in while at anchor I never sleep anyway (way too much noise and frequent anchor checks). The strongest winds (moderate gale) while at anchor were in Cocktail Cove on Lesqueti Island, BC during our 2005 cruise and our system held just fine, albeit noisy and lumpy.

Terry

setting the hook with larger boats

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

Guest