Oversized Anchor perhaps !!

[yelbis]

Hi

Been having a debate with a few fellow boats owners reference my new Delta anchor. I have a Dehler 34 1992. Displacement 3.2 tonnes. fully laden approaching 4 tonnes at a guess.

Anchor is 15kg. This was recommended from known supplier. On numerous occasions shortly after a change of tide I have dragged up to 40 metres setting off the alarm. Rode length and calcs have all been
correct. My opinion is that the 15kg anchor is too heavy once capsized to set correctly if perhaps the boat itself is too light and in some way bobbing about and slowly dragging the hook. Whilst a faster moving heavier boat
will dig the anchor in as designed. Any experience or similar scenarios please advise.

I am thinking changing to a Rocna 10. this meets the specification on their website, although its only a 10 kg anchor.

 

[Sandy]

How much rode? What was the bottom?

My own Knox 13kg on a Gib'Sea 96 just works and its not that different to the Delta.

 

[vyv_cox]

The Delta is a good anchor within its limitations and that size is the same as I used on a Sadler 34 for many years. It does have a tendency to drag in soft mud but in typical Atlantic seabeds does very well. I replaced it with a 15 kg Rocna that has done very well for more than 10 years.

 

[Neeves]

How much rode? What was the bottom?

My own Knox 13kg on a Gib'Sea 96 just works and its not that different to the Delta.

Knox is not much different to a Delta? Maybe your anchor is not a Knox!

Hi

Been having a debate with a few fellow boats owners reference my new Delta anchor. I have a Dehler 34 1992. Displacement 3.2 tonnes. fully laden approaching 4 tonnes at a guess.

Anchor is 15kg. This was recommended from known supplier. On numerous occasions shortly after a change of tide I have dragged up to 40 metres setting off the alarm. Rode length and calcs have all been
correct. My opinion is that the 15kg anchor is too heavy once capsized to set correctly if perhaps the boat itself is too light and in some way bobbing about and slowly dragging the hook. Whilst a faster moving heavier boat
will dig the anchor in as designed. Any experience or similar scenarios please advise.

I am thinking changing to a Rocna 10. this meets the specification on their website, although its only a 10 kg anchor.

Your anchor is new? - what possessed you to buy a Delta.



You could buy a 10kg Rocna, 10kg Excel, 10kg Spade and a smaller Viking, maybe 7kg and you would not have had the nightmare of dragging nor need to post here.

Take care, stay safe

We sail a 38' x 7t cat with the windage of a 45' AWB and when we used steel anchors they were 15kg. Now we use 8kg aluminium anchors. Your anchor was too big - but as Vyv suggest maybe it was in the wrong seabed. Many anchors do not work very well in a soft seabed as they need 'substance' to roll over. In soft seabeds they can drag forever as the shank simply sinks into the mud like a keel.

Jonathan

 

[Stemar]

You could buy a 10kg Rocna, 10kg Excel, 10kg Spade and a smaller Viking, maybe 7kg and you would not have had the nightmare of dragging nor need to post here.

If he had all those, he'd still be posting to brag about it on every anchor thread

 

[Sandy]

Knox is not much different to a Delta? Maybe your anchor is not a Knox!

Both are triangles of metal with different angles. The Knox has a roll bar, handy for lifting.

 

[Neeves]

If he had all those, he'd still be posting to brag about it on every anchor thread

You can never have enough anchors

Jonathan

 

[Rhylsailer99]

i bought a 6kg delta anchor for a 28ft cobra 850 as my old 15kg bruce seemed too heavy will iI be sleeping with one eye open.

 

[noelex]

A smaller anchor is not going to help.

Switching to a Rocna will.

 

[Boathook]

How much rode? What was the bottom?

My own Knox 13kg on a Gib'Sea 96 just works and its not that different to the Delta.

I would add depth from bow roller to sea bed plus how much rope is in the rode.

 

[yelbis]

How much rode? What was the bottom?

My own Knox 13kg on a Gib'Sea 96 just works and its not that different to the Delta.

Low water was depth at 3 metres water not depth from from keel. It was predicted 3 metre high water. I ran 25 meters from water level all 8 mm chain.
Bottom was sand/mud some, weed. Max 15 knots wind and tide would have ran at 1.8 knots. thanks

 

[Neeves]

Low water was depth at 3 metres water not depth from from keel. It was predicted 3 metre high water. I ran 25 meters from water level all 8 mm chain.
Bottom was sand/mud some, weed. Max 15 knots wind and tide would have ran at 1.8 knots. thanks

There is weed and weed.

All anchors can clog with weed, which may have fallen off when you retrieve. They may also collect more weed as they drag.

Both anchors are Delta types, they might be original - it does not matter - would you really expect them to reset easily. Both anchors are on, or under, the bridge deck of different cats - the owner's might not know they were clogged (and the location is difficult to access). Boat type does not matter - nor anchor, rode nor scope.

Steer clear of weed and have a better anchoring experience and protect the seabed




Jonathan

 

[Black Sheep]

On numerous occasions shortly after a change of tide I have dragged up to 40 metres setting off the alarm.

Low water was depth at 3 metres water not depth from from keel. It was predicted 3 metre high water. I ran 25 meters from water level all 8 mm chain.

Apologies if you've already got this covered, but how do you know you dragged up to 40m? With 25m of chain out, you will expect there to be roughly 50m between the uptide position of your bow, and the downtide position. If your GPS antenna is on the taffrail, it will measure 70m between uptide and downtide extremes. Even if you hit the alarm button when your bow is exactly over the anchor, you will expect a swinging circle (measured at the stern) of about 35 metres radius (70m diameter). So it's possible the "40m drag" is just normal swinging around a well set anchor, but you were very slightly off centre when you hit the alarm button. Try relaxing your alarm to a bit more than twice (the rode length plus your boat length) - in this case 70m. Then, no matter where in the swinging circle you hit the alarm button, you know it really is dragging if the alarm goes.

Again, apologies if you've got this covered, or your anchor alarm doesn't work as I imagine.

 

[Refueler]

Apologies if you've already got this covered, but how do you know you dragged up to 40m? With 25m of chain out, you will expect there to be roughly 50m between the uptide position of your bow, and the downtide position. If your GPS antenna is on the taffrail, it will measure 70m between uptide and downtide extremes. Even if you hit the alarm button when your bow is exactly over the anchor, you will expect a swinging circle (measured at the stern) of about 35 metres radius (70m diameter). So it's possible the "40m drag" is just normal swinging around a well set anchor, but you were very slightly off centre when you hit the alarm button. Try relaxing your alarm to a bit more than twice (the rode length plus your boat length) - in this case 70m. Then, no matter where in the swinging circle you hit the alarm button, you know it really is dragging if the alarm goes.

Again, apologies if you've got this covered, or your anchor alarm doesn't work as I imagine.

Don't forget the variable GPS position as well ...