anchoring offshore

[tugger]

read a few posts that have a few fellas looking at going offshore for the first time and may need to know what to take in regard to anchoring. rule of thumb for chain length is you need just over the length of your boat eg. 5.5m boat / 6m of chain . i use a 10mm reef anchor for my 5.5m tinnie but any bigger and you would need a 13mm reefie. length of rope needs to be at least 3 times the depth of water on a good day but up to 5 times on a strong current or ruff conditions. don't just hit the bottom with your anchor and tie off the rope needs to be leading on a 45 degree angle at least or you will drag a fair bit .nothing worse than getting onto a hot bite and you drag all morning .these are just ruff examples and experience will come in time but it should get you started.

ps. a large foam ball with ring helps pull the anchor off the bottom

[noname]

anchoring can be made so simple with a little thought

[kc_ksom]

Thats interesting, I have only 2 mtrs of chain on my ancor rope on a 5.25 tinny, I might invest in a little more. Would you say that in calm conditions this length would change???

Casey

[straddiebrad]

mate how much rope would you need to meter of water well what i mean if your fishing 40 meters of water would 60 meters of rope be enough, like a meter to depth ratio. brad

[tugger]

from 3 to 5 times the depth fo water for rope length brad

[tugger]

casey it pays to have a 6m length of chain for your boat for offshore and have your 2m length for river and creeks

[noname]

depends on a few things brad. i personally don't use 3 times as much rope as per depth, but i have a few anchors. you have to get your anchor chain to lie flat on the bottom at all times, a good way to get a rough idea is to lie your anchor on the grass, grab the last bit of chain and lift it over your head if you can, if the anchor moves, add more chain, hence a fair bit of chain and lead filled anchors being used, you have got to have the anchor shaft firmly on the bottom, my reefie will hold in sand mud almost everytime, so i don't carry a sand anchor at all. moolloolaba seems to be a different story. i take 2 anchors, 1st is a moolloolaba anchor, the other is a reefie, lead filled, but very long shaft and the prongs are bent different, so far so good, i also use 8mm rope instead of 10 or 12 mm rope, less drag and reacts like a shock absorber, a friend has a similar set up using 12mm rope and he is on his 4th anchor now from memory, but i think he has a problem with his bollard at the bow sprit .

[straddiebrad]

thanks tugger.brad

[werewolf]

Ok probably a dumb question but never thought to ask: what purpose does the chain serve?

[tugger]

the chain is to keep the shaft of the anchor on the sea bed so its not trying pull free

[dhess]

3 to 1 anchor scope on a calm day is not realistic for deep water. No one carries that much rope. When overnighting in 56m of water 80m is more than enough.

An important tip when using a retrieving buoy is to only tie off to the bow. Some idiots tie off to a cleat on the back of the boat. Very dangerous. If the anchor doesn't let go you are going down. A boat sank in calm conditions on the Barwon Banks a couple of years ago doing this.

The chains function is to weigh the rope down so the rocking of the boat is not transferred directly to the anchor.

[noname]

the best way to explain this? imagine the ocean floor as being flat! i'm talking reef anchors here, but the same principals.

your reef anchor when lowered from the boat will sit on the ocean floor at an angle, maybe 15/20 degree's. if you only had rope, no chain.

the ocean swell with the lifting of the boat as it rolls over the swell will lift the back of the anchor causing it to drag, sort of like fishing with soft plastic's. with a very light jigg head close to a rock wall, your less likely to get snagged, use a heavy jigg head 1st cast and your snagged, if that makes sence, so the chain serves it's purpose to actually anchor the anchor.

[werewolf]

cheers thanks guys

[bootyinblue]

The chain acts as the shock absorber between the boat and the anchor. As your boat pitches, the chain lifts off the bottom, as the boat rolls the chain lays flat again on the sea bed.

Have a look at a sand anchor and see the angle you need to lift the shaft before the flukes move. Its not an awful lot, so the chain used so the shaft does not lift to the point that the flukses move.

[tugger]

when overnighting offshore and i've crossed a bar i carry 200m of rope in 2 lengths and 1 of those legths is stowed away in case the 1 being used breaks and bringing a second anchor and chain is what i have in reserve. you can't cross that bar to head home at night once you lose an anchor and rope and the duty of care to your deckies is worth that bit extra . my boat stores this extra gear in forward compartments and you don't even notice . i've lost an anchor rope in my mates boat 1 night with the constant pitching of the boat as it sawed threw it at the bow sprit. day trips is a diferent story as you can just head home . i buy my rope in 200m to 250m coils from a rope dealer as its cheap this way compared to BCF stores etc.

[mick fillet]

Replaced my anchor rope last mounth went to bcf ipswich 200 mtrs 12mm $70 for the roll.

[tugger]

thats a top price for 12mm is that silver line you bought mick

[Feral]

The rules are you need minimum 2m of chain and 27m of rope if over 5m, if under you just need 27m of rope.

Both of which would be totally inadequate for off shore work!

[big al]

for rope try-offshore trading 2/27 ada st coopers plains ph 07 32777400 was the best price that i found last year was -$77.90 for 250m of 10mm pe staple silver al

[Lozzel]

Tugger,and anyone reading,I'll try to explain how we anchored the pro reef boats on our marks,It's a little hard to write down but here goes.

Anchor is an "Arrow head design" shackled at the point,chain runs down the shaft of the anchor and ties off to the end of shaft with 3 single strands of 5-6mm nylon. This is designed to brake free when stuck hard and the anchor pulls free from the nose.

First Anchor chain is 13mm x10mts (in our case)connected to 10mts of 19mm rope connected to another 10mts of 10mm chain, connected to the 25mm anchor rope.

How it works is the heavy anchor chain lays flat on the sea floor, the middle rope acts and second chain acts as the shock absorber.

This means that you can have the boat nearly directly above the anchor and it wont pull, example ,if we anchored in say 60mts of water we would only put out 70 mtrs of anchor rope,80 mtr depth 90-100 mtrs of rope. maybe a little more if conditions were sloopy.

I used the same set up on my 6 mtr boat and never had an anchor come off or drag.

I hope I explained this ok ,if not drop me a pm with your e-mail and ill go into a bit more detail.

Laurie.