45' Leopard Catamaran Delta anchor power set rpms

[sailjumanji]

Delta can be replaced with Rocna Vulcan. I did. Happy with it. Delta was crap.

[gregabbiss]

Originally Posted by ks2cs2

I own a 2021 Leopard 45 catamaran (lots of windage) with two (2) 45-hp Yanmars w/ fixed blade props using a 55-lb Delta anchor and all chain. Does anybody have any information on bollard pulls for catamarans?

BTW - changing out the anchor setup is not a variable and cannot be changed due to this is the standard Moorings setup for the new Leopard 45's.

If this helps; We have a Lagoon 450S for comparison and it came with a 25kg (55lb) delta. We struggled to get it to set properly and hold, dragging too many times. We have 57Hp engines and 3 blade foldable props.

We replaced with a 40kg (88kg) Rocnor anchor and have never dragged and only once not set first time.

The procedure we follow is: Let out about 2 X the depth in chain and wait for hte anchor to take hold, either with wind or very gentle idle reverse (if it won't hold, it never will at this point, so just retry somewhere else). My partner uses her foot on the chain to "feel" if it is skipping at all.

After this let out the remainder of what is needed for a total of 3:1 to 4:1 scope depending on expected weather and swing room available and then back down i no it using 1500-1800rpm. Using GPS and visual bearing to check drift.

I usually dive on the anchor after this, when we are in clear and warm water, just to be sure and also see how well our technique works. The anchor is mostly buried completely at this point. So relatively confident in our anchor and technique.

With the delta the procedure was the same, the scope was always more and it just took multiple attempts before we were happy to sleep on the anchor, almost always. once set it was mostly ok. although did drag from time to time if the wind picked up, especially if the sea-state also did.

My advice, 1500-1800 or more to set after getting it gently into the right orientation (first set part is the key to that) then DON'T TRUST THE DAMN thing if the wind picks up

BTW, so very glad to hear someone getting advice and caring about how they anchor. We have seen so many boats drag and no wonder when we have also seen, anchors laying on the bottom point up, Anchors swinging just above the bottom and even anchors sitting on top of their own chain.. no wonder we have also seen boats try multiple times to re-anchor in challenging conditions and even one super yacht drag for 300 mtrs before calling it quits and trying again.

[BillKny]

Originally Posted by gregabbiss

DON'T TRUST THE DAMN thing if the wind picks up

WTF???? Don't trust your anchor???? Then get a different one!!!!

And how much does the wind have to pick up before you "don't trust the damn thing"????

We set our anchor with our FULL REVERSE. It doesn't move. Once set, we have been in winds of 70 knots, and not moved. Do we "trust it"? YES! Do we check it? OF COURSE!

As someone once said, "Trust, but verify."

If you can't TRUST your anchor to hold in storm force winds, you have the wrong anchor for cruising. Just fine for weekend gunk-holing, maybe.

[smj]

Originally Posted by BillKny

WTF???? Don't trust your anchor???? Then get a different one!!!!



And how much does the wind have to pick up before you "don't trust the damn thing"????



We set our anchor with our FULL REVERSE. It doesn't move. Once set, we have been in winds of 70 knots, and not moved. Do we "trust it"? YES! Do we check it? OF COURSE!



As someone once said, "Trust, but verify."



If you can't TRUST your anchor to hold in storm force winds, you have the wrong anchor for cruising. Just fine for weekend gunk-holing, maybe.

No chances of storm force winds while weekend gunk-holing? An anchor should be chosen and purchased to hold the boat, period.

[newlazydays]

Putting my penny's worth here. After many years chartering in the Bahamas my anchors got bigger the longer I was there. I finished up with a 110 lb claw from China on a 51 foot mono hull sail boat. I can't remember dragging with that anchor even in severe squalls. I think that your current anchor with all your windage is far too small for the job.

[gregabbiss]

Originally Posted by BillKny

WTF???? Don't trust your anchor???? Then get a different one!!!!

Strangely that is exactly what we did, as we said in the post. But I think if you read the OP's message fully (as you might have with ours) your'd find he says replacing is not a possibility. Presume he is working with Charter and wanting to know how to get the best out of the little Delta that comes with it.

[double u]

"A well set anchor should withstand a pull at any RPM that you can deliver. "

finally someone has the right idea!

[Panope]

Originally Posted by ks2cs2

..........with two (2) 45-hp Yanmars w/ fixed blade props...............

Does anybody have any information on bollard pulls for catamarans?...............

I measured the Bollard pull of my 40-hp Yanmar (one engine) w/fixed blade prop:

Reverse = 370lbs. bollard pull at max attainable r.p.m. (3500)

Forward = 910lbs. bollard pull at max attainable r.p.m. (3300)

Steve

[Jweyndling]

I have a 55lb Delta on my 42’ cat with an allChain tide And have never had a problem with it dragging. I would normally set back at about 1500 rpm on my two 40ho Yanmars. I suspect that you just had really poor holding where you were.

[Ulstue]

Unfortunately, I also only have experience values. Cat same length, 2 x 56hp, folding props, same anchor (55lb Delta).
Above 1500 rpm it can happen that you pull the anchor away in mud, or for example if it is only a layer of sand on a rock plate. It's clear: with to much power, for examle the power of a motoryacht you would pull the anchor through almost any bottom, or break something. If the bottom is good and the chain long enough, our delta always digs in. If not the ground or the anchor technique / length of chain is not correct. Testing at 1500 rpm (with both motors) is usually sufficient for wind conditions up to 20+. Overdoing it here eliminates many anchorages. That's a lot more power with both engines than most monohulls can pull. Of course, the windage area of a catamaran is much larger. If it has to hold in more wind, I'll pull the anchor in at slowly to 2000rpm-2200rpm, where that won't work, I can't stay if I expect 40knts or more. Then of course also with chain length at least water depth times 7+.

The anchor dimensions Delta 55lbs are absolutely correct for these boats. The weight of the anchor is negligible for the holding power of patent anchors anyway, at least when they are dug in.

[noelex 77]

Originally Posted by Ulstue

If not the ground or the anchor technique / length of chain is not correct. Testing at 1500 rpm (with both motors) is usually sufficient for wind conditions up to 20+. Overdoing it here eliminates many anchorages.

Originally Posted by Ulstue

I'll pull the anchor in at slowly to 2000rpm-2200rpm, where that won't work, I can't stay if I expect 40knts or more.

With modern anchoring gear there is really no reason to put up with this type of performance.

Think seriously about upgrading the design or size (or both) of your primary anchor to something better.

[Ulstue]

Do you say:

- There is no reason to check the anchor's hold with this amount of power?

- I should think seriously about changing the anchor because it holds at 2000rpm and more with 2x 56 hp engines?

Are you kidding? Or have I misunderstood?

[noelex 77]

Originally Posted by Ulstue

Or have I misunderstood?

Yes, I think you have.

A good anchor should reliably hold full cruising revs. Full cruising revs on most yachts is only equivalent to 25-30 knots of wind. This is test that should be done every time. Failure should be very rare.

1500 rpm is not an adequate test. Even 2000 is not enough. If applying more than 1500 "eliminates many anchorages" it is showing that the ground tackle should be upgraded.

[Anders]

55lb delta is tiny for a mid 40 cat. I would not use it for anything bigger than a 35 feet mono if I was using delta!

[Ulstue]

Originally Posted by noelex 77

Yes, I think you have.

A good anchor should reliably hold full cruising revs. Full cruising revs on most yachts is only equivalent to 25-30 knots of wind. This is test that should be done every time. Failure should be very rare.

1500 rpm is not an adequate test. Even 2000 is not enough. If applying more than 1500 "eliminates many anchorages" it is showing that the ground tackle should be upgraded.

You are misinterpreting what I wrote. For example, all anchorages are not usable where there is only a thin layer of sand on rocks, if very good hold is necessary. Except for the anchor hammered in under water with a sledgehammer (joke), there is no anchor that holds well there. In this context, your recommendation to change the anchor goes in a wrong direction, like the rest of your comment. It is not necessary to have an anchor set at each stop that can withstand 20 Knt + wind.