Northwest Dive Club

I'm trying to determine what length and diameter rope to get for my 14' RIB. It's pretty heavy for it's length but still obiously not a terribly heavy boat. I have a 17lb Danforth Anchor that will be way overkill and a smaller one that I may be able to use - gotta go measure/weigh it - as well as about 10 ft of chain. I was thinking along the lines of 300' of 1/4" or 3/8" rope. Do any of you use more than that? I would like to be able to anchor in up 130' under the right circumstances. But according to "conventional wisdom that would mean 500-900' of rope depending on whom you ask. Sounds like an aweful lot. For those of you that have a boat, how much line do you carry and how much scope do you use in the Sound generally? Also, I would estimate that my boat loaded wouldn't top 2000 to 2500 lbs. What would be the minimum diameter rope you'd use?

The bigger the line the easier it will be to pull the anchor so while 1/4 should be fine I think I would go with 3/8. Also consider adding more chain. After dragging anchor a few times I went to 20 feet of chain, which makes it harder to pull the anchor (see the first sentence). I have 300 feet of line, sometimes it would be nice to have more, but most of the sets use 150' or less.

Consider getting a rope bag if you don't have a line locker. Used correctly they keep line so that the anchor can be deployed with no birds-nesting and conveniently store the rode in small space.

I agree, more chain and 300' of 3/8 line. The general rule I go by is 3' of line for every foot of depth and the chain should never be shorter than your boat.

My years of boating have taught me a few things the hard way. Have at least the length of your boat in chain, I would go with 20 feet. The bigger the chain the more it will keep your anchor set by keeping it from pulling up. 3/8 rode should be fine, plenty strong and still easy on your hands.

For your boat either size line should be strong enough. The 3/8" line will be little easier to on your hands and will be slightly more resistant to chafing. I would give some consideration to using a braided rather than laid (three strand) line. You'll probably want to consider a bag or basket to contain all the line.

Thanks for the advice. I think I'll be looking at 250-300ft of 3/8 rope with at least 14 ft of chain. There's a compartment in the bow that I think will do well as an anchor locker. One of the other things i've been considering is getting a VHF radio. Are there any features I should be looking out for? I was just thinking of one of the cheap handheld ones, mainly for comunication with other boats.

Mattleycrue76 wrote: One of the other things i've been considering is getting a VHF radio. Are there any features I should be looking out for? I was just thinking of one of the cheap handheld ones, mainly for comunication with other boats.

The difference between a cheap handheld and a full featured reliable handheld is pretty small, I would suggest getting a good one. IMHO theStandard HX-850s is a great value and should be around $250. It is waterproof, has a decent size battery capacity, has built in GPS, and DSC distress calling (the technology the Nautilus Lifeline uses).

Send me a PM with your shopping list, I can get some pretty good pricing at Fisheries Supply.

What everyone else says. For what it is worth, my RIB (18.5 feet, so bigger than yours) held fine--even when surfing--with 18 feet of 5/8 inch chain and 3/8 inch rode with a 11 pound Delta anchor. For diving, I used the same setup, and carried 300 feet of rode. While conventional wisdom may be 6:1 scope, most of us are getting by with 3:1, and some people use less, although I'd shoot for at least 3:1. Carrying more than 300 feet of rode is a PITA.

If you think about it, there will be very few times you are anchoring in 130 feet of water. Even if you are diving that deep, you are probably anchoring shallower and swimming/scootering downslope. And, tech diving often times means live boating with a tender. I think the deepest I'd anchored was when tending for a class in about 110 feet of water in the San Juans.

A few other suggestions:

Consider a claw or delta type anchor over the danforth. Those types hold way better than a danforth in our usual anchoring substrates.

Also, look for the tags with numbers on them so you can label your rode in feet, usually in 30 foot increments, helps tremendously with keeping track of how much line is out.

Finally, to keep things from rubbing on your hull, have a line with a couple carabiners, attach one to your bow eye, then the second to the rode using a loop, and then cleat the rode off in the boat, but with a bunch of slack so it isn't rubbing on the tubes. A Richard trick.

+1 on the claw.

Lots of good advice above, especially about lots of chain. I used 20' of chain on my old 16' RIB and now use 25' on a 9,000 lb boat. My anchor rode is 1/2" double-braided line (overkill, but really, really easy on your hands) and is probably only 150' long. I've had the chain hold my boat in place even when the anchor was completely fouled (usually in the chain).

We rarely, if ever anchor in more than 70' of water. Our shot line is 200' long and is used for any dive more than 100' deep.

As Doug suggested, you'll most often anchor in shallower water and swim down to the dive site. We often anchor in 35' or less of water which makes it easy to locate the anchor and it makes your safety stop easy.

Another trick we use (on the anchor or shot line) is to put a lift bag on the line as we ascend, with just enough air to keep the anchor in place. This makes pulling the anchor/shot easy as it will help lift itself to the surface as you start to pull.

Good Luck,

boydski wrote:
Another trick we use (on the anchor or shot line) is to put a lift bag on the line as we ascend, with just enough air to keep the anchor in place. This makes pulling the anchor/shot easy as it will help lift itself to the surface as you start to pull.

Good Luck,

That is a good one, particularly useful when in areas where it can snag or foul when lifting it off the bottom.

that is a slick trick

I use an 11lb claw about 5ft of super heavy 1/2"+ chain and 10ft or so of lighter 1/4" chain. The heavy chain keeps the shank of the anchor (the part you tie into) parallel to the bottom for the best hold without be super long. The whole deal weighs at least 25lbs.

Pulling it from substantive depth is a beetch. Get one of these gizmos:
http://www.anchorpullers.com/
You still won't want to anhcor in 130ft. More like 90ft max with 300ft of line. As others have said 3/8" is easier on your hands than the suitably strong but thin 1/4". Memphis Net and Twine has good prices on line (much better than local).

Please don't ever anchor on a wreck in Lake Washington. None of them tolerate anchoring and even the most robust looking wood is so waterlogged it will rip up. Use a shot line with ~5-8lbs of soft lead in a bag or as ankle weights. Then anchor upwind and let the boat sit back where the shot buoy is, or live boat.

CaptnJack wrote:I use an 11lb claw about 5ft of super heavy 1/2"+ chain and 10ft or so of lighter 1/4" chain. The heavy chain keeps the shank of the anchor (the part you tie into) parallel to the bottom for the best hold without be super long. The whole deal weighs at least 25lbs.

Pulling it from substantive depth is a beetch. Get one of these gizmos:
http://www.anchorpullers.com/
You still won't want to anhcor in 130ft. More like 90ft max with 300ft of line. As others have said 3/8" is easier on your hands than the suitably strong but thin 1/4". Memphis Net and Twine has good prices on line (much better than local).

Please don't ever anchor on a wreck in Lake Washington. None of them tolerate anchoring and even the most robust looking wood is so waterlogged it will rip up. Use a shot line with ~5-8lbs of soft lead in a bag or as ankle weights. Then anchor upwind and let the boat sit back where the shot buoy is, or live boat.

Roger on the not anchoring on wrecks. Environmental impact aside, from my limited experience the silt disturbance from the anchor alone could easily be enought to blow out viz. After thinking about it, I'm leaning towards scaling back my achor depth expectations a bit. I'm now thinking that 150-250ft of 3/8 inch should do just fine. Have you guys had any experience with line colors other than white? I was looking at this stuff and It seemed like a good deal, but I'm not sure if it would be harder to see under water. http://cgi.ebay.com/ebaymotors/Dbl-Brai ... 0477379363

Mattleycrue76 wrote: Have you guys had any experience with line colors other than white?

My anchor line is bright blue with white stripes, which makes it very easy to see in our pea soup. However, it came with one of my boats, so I'm not sure it's worth paying extra for. We use white for our shot lines and that works too.

Good Luck,

Lots of good info here. Danforth anchors are really only good in sand. I use an 8' coated 5/8" yacht chain and a 20# anchor with my 22' boat. 3/8 or 7/16 rope is the way to go, and make sure that it is solid braided nylon (the cheaper version with a foam / poly core doesn't work well). A good quality laundry bag works well as a rope bag. A crab buoy or two on the end of your line (inside the bag) will save you grief if the line ever gets dropped overboard or if you ever leave the anchor and take the boat to shore (I use a an A-2 buoy on an EZ-Puller, and one crab float in the rope bag). Finally, I would get 300' of line. If you ever have to anchor in heavy current, you won't regret having more line (I've finally gone to 500' for my current boat, but I've used needed all 300' that I used to carry in much smaller boats).

I've used a purple blue color once, its was really a pain to see. Not sure about the green but white or yellow with flecks and/or braided is much nicer.

Good point by dsteding about the rode tags, they really help to know exactly how much line is out. They are easy to install in laid (3 strand twisted) rope, I don't know if you can put them in braid, I suppose if it is a loose braid you might be able to. One thing you want in anchor line is a lot of stretch to absorb shock on the anchor.

My experience with anchors:

Danforth: As mentioned above good in sand, but not so much in other substrates. Not a recommended anchor for a RIB since it has TWO sharp points and two more dull ones on the ends of the bars that serve as the stock.

Claw (or Bruce): Better for a RIB (fewer sharp points), but it does not hold well in sand or gravel in my experience. I got fed up with mine anchored in sand in 40 feet of water with 200 feet of scope and a strong wind and some swell. The anchor just kept plowing a furrow in the sand and wasn't going to stop until it hit something solid.

That led me to a Rocna: similar to a plow anchor with only one sharpish point. I've never had it move on me yet. Downsides are that they are a little harder (but not much) to stow and they are expensive relative to a knock off Claw anchor. The following link is marketing BS but I think it is justifiable marketing BS:
http://www.rocna.com/rocna-world/rock-s ... t-results/

And that lift bag trick is pretty nifty, would never have thought of it myself.

BTW my Claw is for sale ;-)

Steve

CaptnJack wrote:I use an 11lb claw about 5ft of super heavy 1/2"+ chain and 10ft or so of lighter 1/4" chain. The heavy chain keeps the shank of the anchor (the part you tie into) parallel to the bottom for the best hold without be super long. The whole deal weighs at least 25lbs.

Pulling it from substantive depth is a beetch. Get one of these gizmos:
http://www.anchorpullers.com/

X2 That is about the same setup I had on my RIB. I have a heavier claw anchor and more chain on the new boat and it works great.