Anchoring

[Jono Garton]

Hi

On a course today (the students are in the other class room now), we got in to a long discussion over Anchoring. For an average size RIB I have allways been a fan of a decent anchor, 3 - 5m of chain and 3 - 4 times the max depth depending on conditions and carrying 30 - 40m of Anchor Warp and allways being able to join with the other warps on the boat.

What do you use?

I see the "Start Powerboating" book (you know the one without a section on tides) reccomends 6 x the depth.

Cheers

Jono (very much a 4 x fan) Garton

[Nos4r2]

Pretty much the same as you. My anchor is a bit smaller than it should be (small anchor locker) but I've only ever had trouble with getting it to hold in short chop. Once it's in, it holds ok.

[SeaSkills]

I've got a Bruce and a CQR, both above minimum size for the boat, both with chain (8m on each) then warp. I tend to put down about 5x depth as either all chain or chain + warp.

I just don't think anchors are something to be stinted on. It's not so bad if you're stopping for a picnic or a swim, but if I lost power on a lee shore with breaking waves I want to be pretty certain I'm going to hold.

[Jono Garton]

Hi

So if you anchor in 15m of water, you put down 75m of chain what boat have you got?

I agree its better to be safe, but if you got your life jacket caught in 20m of chain and an anchor, im not convinced you would float???

Jono

[Cypman]

i'm with you on this Jono, 1kg anchor weight for each metre of boat length ( I like Bruce types best). Anchor chain equal to boat length, and 50m of rope (10mm is strong enough for most RIBs under 7m long)

[Polwart]

I have a 4m boat, and IIRC it carries a 4.5 kg Danforth with 5 m of 6mm chain and 30m of 8mm rope. Never had it slip - but never been tested in really bad weather (>F4) either. I don't have a depth sounder (but do carry a home made "lead line") and try to put out 5x depth as scope.

[yoyo]

Originally Posted by Polwart

I have a 4m boat, and IIRC it carries a 4.5 kg Danforth

Is it anchor wieght or surface area and design that counts? I use a Fortress, Danforth style which is made from Ally. lighter but large surface area.

[Polwart]

Originally Posted by yoyo

Is it anchor wieght or surface area and design that counts? I use a Fortress, Danforth style which is made from Ally. lighter but large surface area.

both - but you are right you need less weight if you are comparing ali to steel. mine is steel.

[BogMonster]

Originally Posted by Jono Garton

So if you anchor in 15m of water, you put down 75m of chain what boat have you got?
Jono

One with the prop out of the water

[codprawn]

Anchor weight is mainly to aid penetration. Surface area is definitely what counts unless you are anchoring on rock where a grapnel or fishermans is great.

I carry 2x 60m of 16mm octoplait - mainly because the bigger diameter is easier on the hands. My working anchor is a 5kg Bruce just attached direct to the rope. it works fine in most conditions. For emergency use I have a 6kg Delta copy with 8m of very heavy chain(can't remember size). Obviously if I need to I can join the 2 lengths of rope together so I have 128m in total which is 420' in real money.

A 3x scope is fine in most conditions with chain. In storm conditions even 5 or 7x may not be enough.

Remember chain is only there to keep the pull horizontal so a short length of heavy chain will be better than a long length of lighter stuff. Of course chain is pretty wear resistant!!!

I suppose this is why an angel is a good idea.

In South Wales especially the waters are very shallow. 100' is about the most we get. Imagine people living in places like Tenerife - 1/2 a mile out you get 14,000'.........