Grapnel Anchors Advise

[Locozodiac]

Been offered grapnel folding anchors for sib uses, find very practical with easy storage, in the dilema of picking the right one from 2 models : To be used on 3.80 sib ( 12.4")

A (boats 5" to 10") weight 5.5 lbs
B (boats 5" to 15") weight 7.0 lbs

Don't have tech specs for both, could both be same size with just different weights ? Assuming same size, would anchor A be ok for a 3.80 sib ? Have a small light fortress type anchor that weights about 4 lbs and anchors a 380 sib prefectly with 2 meter chain attached to it, we don't have strong currents, winds. Any thoughts, ideas will be appreciated.

Happy Sibbing

[m chappelow]

think they are if your not intending to do much anchoring but they seem to need a lot of chain, there not too bad in rocks and boulder types of sea bed and not too bad in kelp or heavy weed but on sand or mud they seem poor ,they will often tumble or spin around and skip over the bottom if any tide running without digging in and if the lock ring is loose or worn unless it is wired up the whole lot can collapse,think i would stick with your fortresss type,but as you said in your area theres not much wind or tide so it maybe ok for you to use the A but you will need more chain or an angel weight a few metres from the anchor ,

[codprawn]

they are next to useless in sand or mud - I had a 7lb and a 14lb and even the bigger one could be pulled along with one hand.

Danforth types like the Fortress are great in sand and mud but not much good in rock.

Either carry both types or get a Delta/Spade/Bruce as a good all rounder.

[Locozodiac]

Originally Posted by codprawn

they are next to useless in sand or mud - I had a 7lb and a 14lb and even the bigger one could be pulled along with one hand.

Thanks for both inputs, incredible to read they don't work well in sand, Manufacturer has not specified what type of bottoms is recommended for ?

"Perfect for use with dinghies and other small craft. Stows neatly and has no sharp points to damage inflatable boats. Has a weighed shank to insure a quick set and is hot dipped galvanized for maximum corrosion resistance".

Liked the folding & storage issue. Will the anchor lock to sand bottom if you pull with sib engine on reverse ? The cost is very cheap: A $ 16.00, B $ 18 + shipping.

Happy Sibbing

[m chappelow]

Originally Posted by Locozodiac

Thanks for both inputs, incredible to read they don't work well in sand, Manufacturer has not specified what type of bottoms is recommended for ?

"Perfect for use with dinghies and other small craft. Stows neatly and has no sharp points to damage inflatable boats. Has a weighed shank to insure a quick set and is hot dipped galvanized for maximum corrosion resistance".

Liked the folding & storage issue. Will the anchor lock to sand bottom if you pull with sib engine on reverse ? The cost is very cheap: A $ 16.00, B $ 18 + shipping.

Happy Sibbing

the stowage side of things are great its just the holding power in soft seabeds , think of the surface area of the flukes compared to somthing like a fortress or danforth ,

[willk]

Grapnels are sometimes affectionately referred to as "lunch-hooks" - fine for calm weather when you're in control of events and having a quick R&R. Not so sure I'd want to rely on one in an emergency. But better than the diving cylinder and a painter "anchor" that I actually witnessed save two lives (three, if you include the Mutt on board).

[Apherel]

We've just been using these with a small tender rib on sandy beaches during a charter. The area was reasonably tidal and for piece of mind we buried the grapnel by hand and put a few large rocks on top of the chain.

May not have been absolutely necessary, but shows our lack of confidence in the holding power in sand!

[Locozodiac]

Originally Posted by Apherel

We've just been using these with a small tender rib on sandy beaches during a charter. The area was reasonably tidal and for piece of mind we buried the grapnel by hand and put a few large rocks on top of the chain.

May not have been absolutely necessary, but shows our lack of confidence in the holding power in sand!

If I got the idea correct: the anchor is no good because cannot secure itself properly or well burried on sandy bottoms, or even securing properly will free itself easily ? Would it be a matter of adding extra weight to the anchor or maybe larger & thicker chain, etc.

[codprawn]

I can drag the 14lb anchor through hard sand with just one hand - easily!!!

I was really shocked - thought it would be a lot better than that but it's all down to surface area as someone has said. That's why Fotress anchors are so good in the tests - because they are made of light alloy people will compare them with anchors of the same weight - a 14lb fortress is huge compared to the 14lb steel one.

The ultimate in sand would be a buried parachute - and that weighs next to nothing!!!

[Apherel]

From observations the have a fairly light chain (which is why people use them) and the horizontal pull doesn't seem to result in any leverage to pull the flukes down into the sand, so they just pull through the top inch or two where there is no resistance.

They worked great around coral heads where they would snag, so would be OK around rocks.

We have a lot of sand and use these anchors, also cheap and light weight, but not as easy to use on jetskis or small sibs.

[Channel Ribs]

Originally Posted by Locozodiac

A (boats 5" to 10") weight 5.5 lbs
B (boats 5" to 15") weight 7.0 lbs

C Stick with your real anchor

I used a grapnel once with a SIB, now I invariably take a small danforth.

In my view and experience folding grapnels are for canoes or jet skiis, lunch-hook is an excellent name for them.

[jyasaki]

Originally Posted by Locozodiac

If I got the idea correct: the anchor is no good because cannot secure itself properly or well burried on sandy bottoms, or even securing properly will free itself easily ? Would it be a matter of adding extra weight to the anchor or maybe larger & thicker chain, etc.

No, an anchor works by a combination of anchor weight (ensures that the anchor penetrates the substrate), fluke (or other equivalent displacement object) design such that it a) orients itself to set, and b) tends to bury itself deeper with greater pull. The chain is there to make sure the anchor line pull stays in a relatively horizontal direction at the anchor (also helps avoid chafe, but that's a different matter.)

The problems with the grapnels is that a) it's not heavy enough at the flukes to penetrate the bottom very well, and b) the flukes are relatively tall and thin (not to mention sitting in the bottom at 45 degree angles), and offer very little resistance in soft bottom compositions.

Compare that to, say, a Danforth, where the anchor weight as it sets is brought to bear on the two fluke tips, which helps it penetrate. Then once it's buried, the entire flat surface of the flukes offers resistance to pullout.

Grapnels work well on irregular hard bottoms (make sure you have a trip line rigged), but are useless on smoothish hard bottoms or just about any soft bottom.

jky

[codprawn]

The Delta is probably the best all rounder. It is great in sand/mud and works fairly well in rock without getting too badly stuck. It is like a a CQR without the annoying hinge.

The Bruce is great but can get a rock stuck in it's flukes.

The Danforth is prob the best in sand/mud but not much good in rock.

Here are some Deltas I sold the other day - I kept the 6kg for my RIB - the others were a bit big!!

[Locozodiac]

OK, anchor gurus, thanks all for the tech advise, so a small damforth is the way to go on sandy/muddy beaches, that's the model regularly used, the advise was for a grapnel anchor that have not the possibility to see, ask about or test.

Happy Boating

[m chappelow]

Originally Posted by codprawn

The Delta is probably the best all rounder. It is great in sand/

Here are some Deltas I sold the other day - I kept the 6kg for my RIB - the others were a bit big!!

hi codders ,whats the holding power of the 3 bladed one ,

[codprawn]

Originally Posted by m chappelow

hi codders ,whats the holding power of the 3 bladed one ,

Thats not an anchor - I bought that to generate electricity from the local rain water sewer.