Anchor and line advice, please

[Mikefule]

Hi. I have a 3.1 metre Zodiac SIB with a 9.9 hp engine, likely to be used mainly by two of us in the summer for cove-hopping and coastal exploring. I've done a fair bit of that in the past in different SIBs.

In this smaller boat, space and weight are at a premium.

I have two anchors left over from earlier projects but of course I would be OK buying a different one if needed.

My current anchor rope is about 50 metres of blue polypropylene twisted rope - a bit cheap and nasty, but it did the job for many years. It is now looking tired and rust stained from long storage, and may have deteriorated.

I guess 50 metres is a reasonable minimum - allowing about 4 times the likely depth in the sort of places I may need to anchor. What would be my best choice of rope in terms of type and diameter/weight? A thin rope that takes up less space would suit for the times it isn't being used - but of course it needs to be more than strong enough when it is being used.

Also, what length and weight of chain at the anchor end?

And finally, anyone got a suggestion for a minimum anchor weight?

Thanks.

[willk]

I have a similarish setup. I allow that I'm not going to be out in marginal weather so the ground gear is for use in up to a F4 (small waves and moderate breeze.

I carry a 2.5kg Bruce anchor with 4m of 6 milly chain, a 75m warp, a 15m warp. The 15m rope is a light braid - around 8mm I'd guess. It is easier on the hands and long enough for any inshore work. The 75m "rope" is maybe 6mm braid and packs away into a tiny hank - it's easily strong enough to hold the boat, but would be harder to haul in.

I chose the Bruce as it works well in many ground types, is light for it's holding ability and has no sharp points. All of this and more fit in a small bag that I keep in the bow.

Have a read of this thread: http://www.rib.net/forum/f50/what-ki...sib-42712.html

[jyasaki]

Nylon is better for anchor line. It has a bit of stretch, which helps reduce "snatch" loading in swell.

Polypropylene has the added disadvantage of being rather UV sensitive; when it fails it pretty much just falls apart. Twisted is better than braided in this regard, though, so you have that going for you.

For a small boat, 5/16" would do OK, but can be hard on hands due to the thin diameter. I'd say 50 or 75m of 3/8" twisted nylon (depending on where you plan to run - you want enough to, in an emergency, be able to put the hook down to stay safe; not necessarily just where you want to hang out.)

jky

[Peter_C]

Poly is also not very good at holding knots.

I carry 100m of 3/8" 3 strand line, and use a danforth style anchor with around 4.5m of chain. Depending on your coast you might be able to go for less line, but as our shores can drop quickly and the anchor is a safety device I prefer to have more than less for staying from shore breaks. Bruce anchors works great for many substrates.

Some will mention the folding grapnel anchor. Many of us are completely against them, unless you NEVER plan to the leave the boat while it is in use.

How you attach to the boat may or may not be important too. I quickly made up a bridle to disperse the load on the d-rings.

My anchor crate setup. The milk style crate works awesome as it vents, and holds the anchor in place. My new one also has a mount for the bow light, and bungee mounts sewn on to mount it in the boat.