Power setting the anchor

I've been following a thread on the cruising forum website about how much power to use in reverse to set the anchor. Most on this site have yachts and they say they use near full power for a few minutes after setting the anchor to really dig it in and prove it will hold in a strong blow.
My question to you all is, how do you set your anchor and how much power do you use to power set the anchor.
My boat is a Grand Banks42 with a Rocna 40 KG and 100 metres of 10mm chain.
I drop anchor then move back slowly paying out 6 x scope then pull back to put tension on the chain till it's straight then I relax it the gently reverse till it's tight and keep the boat in reverse on one engine at tick over while feeling the chain and taking a transit. If it hold still for 30 seconds I relax the pull and then bring it under tension again. If it still passes the 30 seconds test I add the second engine also at tick over and hold this for one minute. If the chain feels solid and the transit is good then job is done and I add the nylon snubber.
Do any of you experts out there use more power than I do to set your anchors?

Brian

No Ice.

Happily cruising Croatia as we speak.

I forgot to add that I adjust the scope after setting to suit the anchorage and weather but normally use 5 x distance from anchor pulpit to sea bed.

Brian
No Ice.

Your procedure is sound and should work in most conditions. When the chain gets straight under moderate power and you aren't moving then you know the point of the anchor is digging in. Any subsequent wind force (in the same direction) will bury it further.

The downside to digging it in really deeply is if the wind shifts then that deep anchor has to work its way around to the new wind angle. Since wind shifts like this often are accompanied by stronger winds, I would prefer the whole process starts with the anchor partially buried so it can twist around easier.

The only time I would power down hard on the anchor is when I was already in high winds and in that case they tend not to shift.

You will know how much power to use in forward to balance the wind as you move forward to set the anchor. Most boat props are half as efficient in reverse so maybe use 50% more rpm than that to set it hard.

A GB 42 which is likely to have twin 135 hp Lehmans will pull quite a force at full reverse power. That will bury the anchor very, very deep if it holds.

David

No Ice, for a Rocna, that's plenty. Some older anchors like the CQR types need a harder pull to be sure (personal experience), but the newer roll bar types will usually just set with enough reverse to lay the chain out and a gentle tug. I often don't even bother with that if there is a bit of wind or current, but just let that set the anchor. Works for me...

Identical arrangement, 40 kg Rocna, 3/8" chain. Generally we are 5-6 to 1 on the scope, in 30 ft depth we let out 200-250 ft of chain.

We let the usually good winds (15kt +) settle us in for a couple of minutes and then power down at 1200 rpm on a single Lehman 135.

No Ice said:

I've been following a thread on the cruising forum website about how much power to use in reverse to set the anchor. Most on this site have yachts and they say they use near full power for a few minutes after setting the anchor to really dig it in and prove it will hold in a strong blow.

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Hard to wade through some of the apples and oranges over there, sometimes. A sailor using "full power" might be talking about 32-hp. If I used "full power," that'd be 900-hp. I think you're right to break it down into smaller pieces.

-Chris

In decades of anchoring on both coasts I have never backed down as hard as some say.

I've had them fail to set but once set they seem to stay. Of course I use lots of chain and scope.
After you really bury them what do you do when the current or wind changes direction at 2AM?

sleep tight...what happens during a hurricane that passes nearby?

your anchor gets buried as deep as it probably ever will and then the wind changes nealy 180 degress for the second greatest pull it ever gets...

anchor manufactures and so many anchor enthusiasts claim their anchor will hold in that kind of blow....so...what's gonna happen?

I would hope all but Danforth style anchors have a shank that will only bend at some force greater than the normal breakout pull anyway.

I like to anchor in places and/or situations that my chain holds me...the anchor is just there for show....

Your setting method seems sound to me Brian.

How do you secure the chain(with an all chain rode) while backing down? Do you use the windlass or snub off with another line? Where I do a majority of my anchoring, Once the anchor starts to set with wind and/or current, I snub it off and have never had a drag problem. I am in NE FL with mostly hard sand with a 60lb CQR and all chain.

I set my anchors at 1400rpm in reverse w a 40hp 30' boat. The rode "seems" quite tight to me and I'm always on the bow to pull on it to check. I pull on the rode/line at right angles halfway between the bow roller and the dedicated anchor cleat.

I have read and heard many times the best way to set an anchor is to do it very slowly. Some call it "soaking" the anchor. Also it seems quite obvious to me that the higher the performance of the anchor the less setting needs to be done. If your anchor is 100% dependable you should not need to set it at all. No such anchor exists of course. But setting is actually, IMO a test of the bottom and not the anchor. That may or may not be true if the anchor dosn't set. Could be the bottom and could be the anchor. You can go find another anchor or go find another bottom. But if you've got a good bottom and an anchor that sets well setting the anchor would be somewhere between not very important to largely a waste of time. However the bottom is the biggest anchoring variable. But if I knew a blow was coming and I had a small Claw anchor I'd set it slowly and as deeply as I could.

Perhaps a more important thing re deploying an anchor is laying the anchor and rode out. If you just dump the whole thing on the bottom all sorts of things can go wrong. When the anchor touches bottom I stop feeding out line. I signal my wife at the helm to back down. After way starts she does that by occasionally bumping reverse by my direction as I watch the water and sense speed and at the same time considering the tension on the line. When way starts I feed out rode as slowly and as closely as I can to lay the rode down in a straight line. When setting scope is reached I have Chris bump the power to slowly and gently at first take the slack out of the rode. Also I hold the line in my hands while standing and feel the "texture" of the bottom. Some anchors set so quickly this step ins not possible as no dragging of the anchor takes place. I slowly (or in some cases very slowly) increase tension until 1400rpm is reached. If it needs anymore setting that that the wind should do fine and the wind sets an anchor best ..... slowly.

manyboats said:

Also I hold the line in my hands while standing and feel the "texture" of the bottom.

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I know you mean laying your hand on the rode after it's been tied off to feel if the anchor is bouncing along the bottom, but I can't shake my image of you with one foot on the bow, the rode wrapped around your forearm whilst your heartiest pirate laugh echos throughout the anchorage.

Brian, every thing sounds ok except I would use the snubber while setting the anchor. I don't want that much load on the windless.

Shay

Shay said:

Brian, every thing sounds ok except I would use the snubber while setting the anchor. I don't want that much load on the windless.

Shay

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Right. Also if there is a bow anchor pulpit there will be a tremendous load applied to it. It is much better to transfer the load to a cleat or eye with a good backing plate.

HAHA Murray ..

I do it very slowly wearing gloves. When the anchor actually begins to set I quickly loop the line around the big cleat and stop the boat.

I'll work on the pirate laugh.

Idle power usually will suffice.

I lay out the anchor and chain as I drift back so it doesn't pile up. Then when I reach the desired ratio, I first let the current set it and stop the boat. After a few seconds, I set it with idle reverse power from twin 85 HP Perkins.

We anchor in 15-50 feet of water, mud bottom with great hold on a claw anchor. 120 ft of chain, the rest rode. Since we don't set with lots of power, we do it on the windlass, then secure the line/chain via cleat and snubber.

We just idle in reverse 'til the slack in the chain is gone and the GPS speed shows zero. Give it a bit if throttle for a couple seconds and verify the speed is still zero. Put the snubber on, shut the engines down, and break out a cold one.

Thanks to you all for your input. To answer the question, do I set the anchor using a snubber to remove the load off the windlass, the answer is no but I take the point and will in the future.
I also should have added to my opening question that I have two 315 HP Cummins engines so that's why I use tick over revs to power set the anchor.
Does anyone with similar sized engines use more power than this?

Brian.

When we power set the anchor we use a snubber - a bridle actually - so that the pressure is off the windlass. Once with my old windlass the bridle slipped and the pull hit the windlass and snapped the windlass' break bar.

While we have a well mounted beefy windlass, I don't think that either the deck or the windlass were designed for the loads that are present when we power set or even when the boat is at anchor in 30+ kt winds.

Being on the Mississippi River I've found the current does a fine job of setting my FX-37 and the longer I stay the deeper it goes. In less current or slack water I use 1 engine in reverse at idle for 30 seconds or so, I normally anchor in 10' to 20' and put out 100' to 150' of chain.

I have a 35 Danforth and all 5/16 chain. I let the wind "tease" the anchor in to set it initally at approx 60 feet (maybe 5 or 6 :1), then I let out to 9 or 10:1 then let the wind set it a little deeper. Then I rig my snubber (single 1/2 inch 3 strand nylon) then I'll use idle or maybe up to 900 rpm in reverse to dig it in. Single FL 120 so that ain't much power.
That has worked fine for me.

I have twin 270 cummins and only use idle. Anything more could case damage to the boat in my opinion.

Same as articspud for us. I have all chain out so I just idle until the boat arrests and then set my snubber. I have given it more power but it is not necessary. I prefer to keep the strain off of the windlass and bow pulpit....

Just for a contrary point of view, dropping a new design hook, then immediately backing down on it makes zero sense to me, and we never do it. In my (apparently solitary) view, powering in reverse on an anchor that isn't set in order to set it does the opposite. The rode goes tight, the shank lifts off the sea bed and an anchor that might be settling in for a good set starts plowing. If you must back down, do so a couple hours after dropping the anchor. That gives time for the hook to nestle into the sea bed and dramatically improves set. IMO and experience, the kind of tug and release that is experienced at anchor will bury most hooks, while power backing with an immediate steady strain equivalent to 40 knots on them will pop many hooks out.

Delfin I think you're right.

Slow setting an anchor is best.
But most of us don't have that much patience. An attitude of "get-er-done" like we do everything else in this culture prevails.
Pulling on the rode lifts the shank unless you've got out lots of scope and lifting the shank is the best way of breaking out there is.
I often look at an anchor's geometry and judge if it should work better at short scope. I think it can be easily seen that the Claws should have less of a tendency to pitch up and break out (w the same angle of pull from the rode) as other anchors. This angle is adjustable on the Fortress and the Super Max. And I think many anchors that set normally on their sides suffer because their throat angle can't be very wide or they will not set well. The tip of the fluke will be too much "sideways". And the reputation of Claws holding well at short scope is well known.

IG36, twin 120 Lehmans, Super Sarca. We idle reverse paying out chain. Once it sets, idle reverse until resistance, then give it a little more reverse, depending on depth, chain out, conditions. Snubber goes on post set, seems ok on the 33yo. Muir windlass, it got a new motor recently, gearbox/drive needing no service other than greasing.

Delfin said:

Just for a contrary point of view, dropping a new design hook, then immediately backing down on it makes zero sense to me, and we never do it. In my (apparently solitary) view, powering in reverse on an anchor that isn't set in order to set it does the opposite. The rode goes tight, the shank lifts off the sea bed and an anchor that might be settling in for a good set starts plowing. If you must back down, do so a couple hours after dropping the anchor. That gives time for the hook to nestle into the sea bed and dramatically improves set. IMO and experience, the kind of tug and release that is experienced at anchor will bury most hooks, while power backing with an immediate steady strain equivalent to 40 knots on them will pop many hooks out.

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Couldn't agree more Delf, with respect to the newer designs. With the old CQR types if you didn't give them a quick tug to engage the bottom, often they would just lie on their side, and especially with that damned hinged shank, they could just gayly bounce along the bottom forever. Especially if there was weed around or a firmish bottom.

Seem to always have a two-knot-or-so tidal current, so hadn't the need to use the engine to dig in the anchor. I'm more concerned of the four-times-a-day tidal reversal rather than the initial anchor setting. So far, the claw has kept stuck in the heavy SF estuarian mud.