Who's got a boat here?

[CaptnJack]

I have a boat, a 15.5ft RIB actually. This is my 2nd "dive boat", the first being a much smaller soft bottom 12.5 sport boat inflatable.

I have upsized my anchor from my previous version but it still ain't cutting it. I have dragged the 15lb Navy anchor several times, mostly on gravel bottoms. Even with oodles (7 or 8 to 1) scope. So I'm looking for a replacement. I have 6ft of lightweight chain attached to 8ft of super heavy 3/8" chain. The pull on the anchor tends to be horizontal and its still dragging. Last weekend I had to manually set it in a tire. The Navy is fine for sand and mud but drags on gravel for some reason. The flukes aren't pointy enough to dig between the rocks I guess. The grapel style (tried it) drags too.

I have used Danforths in the past. They don't seem to work good on dive boats cause they require lots of scope to set. Even though I have 365ft of rode aboard in 100+ft of water its not enough.

As far as I can tell this leaves:
Claw, aka Bruce and other copies. 11lb is about what I can manage by hand. Not too pricey which is good. Supposedly good on short scope.

A 15lb CQR. Probably the highest quality but pretty expensive ($300)

A 14lb Delta. Has not gotten very good reviews lately. Hard to tell if it sets well on short dive site scopes. Slightly smaller than the Claw designs which is good for stowing.

What are other local folks using when anchoring on sites where 8+ to 1 scope is physically impossible?

[Maverick]

Hey jack,

I don't Have a salt water bot anymore, i have a weld craft 18.5ft white water sled for the rivers, like running up hells canyon in the upper snake river. i use a columbia river anchor at 45#'s and it holds in current in a river in gravel at river flows of 4800cfm, thats alot of damn water flow.

these anchors are bad to the bone and is what i used in my tracker when i used to have a salt water boat. they are pretty cheap at gi joes. don't buy the cheapo though, buy the one for about 130 bucks. if you don't like it just take it back, even after use.

It has a cool feature if you can't release the anchor, say it is stuck on the sea floor give two strong tugs from directly over the anchor (not when line is out, move the boat above the anchor) and it folds and comes free. a great anchor style and well worth learning to use. if you would like to borrow mine you can, i can't use it right now, no truck to pull my boat. i loaned it to a friend to move his bed and he gave it back to me totalled, so i will buy a new one as soon as i get the check.

let me know, would be a good reason to meet you and dive on the boat


Maverick

[Dmitchell]

I have a 22' Hewescraft and anchor it with a 22lb Danforth with about 30 feet of 1/4" chain.

I never use 7:1 scope, even though that's what's recommended, it's crazy the swing is way too much. I can usually get away with 1.5:1 in up to 300' of water if the tides not ripping to much. I frequently anchor in 300'+ and have never seen the end of my 600' rode.

I'd can the navy anchor, those are for lakes. Go with another danforth or plow style and get more chain or at least move the heavy chain to the rode side so that the pull is more horizontal than vertical. You want the chain to do the bouncing not the anchor.

It really shouldn't take a heavy anchor to anchor that little boat. My brother in law used to anchor a 25' cabin cruiser with a little 13lb aluminum danforth.

Dave

[boydski]

Hi Richard,

I anchor my 5800#, 22' Dive Boat with a wee little 9 lbs. anchor (the same anchor I used with my Polaris RIB). It is a Danforth clone, which is actually a Navy LWT style, fluke anchor (rather than a plow anchor). The original LWT's had different chocks that were used to set the anchor flukes at different angles depending on bottom type. I haven't drug my anchor (much) yet. It does drag a bit on hard rock bottoms, but any anchor will.

I use quite a bit of chain (~ 25') on the anchor, which is really what makes it hold. As for scope, I use about 1.5 - twice the depth. However, I usually try to anchor in 70' of water or less. If the site is really deep, we use a shot line and take turns diving.

I actually have a spare 14 lbs Danforth, but have never felt the need to use it. One of the advantages we have as divers is that we can go check the set of the anchor (and I will re-set it underwater if I don't like how it looks) when we start our dive.

Are you setting your anchor when you deploy it? When I used to work as a Captain on an oil rig, we used to use 45,000 lbs anchors, which we pretensioned to 350,000 lbs. For the dive boat, we just set it with the motor idleing, in and out of reverse.

[Dmitchell]

boydski

What prop are you running on that thing? I've got to get a new one and am thinking 15-1/2 x 17 SS but am polling everyone with a similar hull as mine that I can before I lay out $650 for a prop that I don't like.

Dave

[boydski]

boydski

What prop are you running on that thing? I've got to get a new one and am thinking 15-1/2 x 17 SS but am polling everyone with a similar hull as mine that I can before I lay out $650 for a prop that I don't like.

Dave

Hi Dave,

My 250 HP Yamaha has a 15 1/4 x 19 SS prop, which works very well. The boat runs very smooth and economically at 4000 RPM, even fully loaded with LOTS of dive gear. Do you have a picture of your boat posted somewhere? I forgot what it looks like.

[Dmitchell]

Right now it's got a 14 x 19 Al on it and I'm getting 32ish at 4800. 45+ at 5900. But I should be cruising more like 4200 IMO.




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Dave

[boydski]

Right now it's got a 14 x 19 Al on it and I'm getting 32ish at 4800. 45+ at 5900. But I should be cruising more like 4200 IMO.

Dave

I'm getting close to 30 at 4000 if I get it trimmed out right, and the boat seems to like that speed. The cabin extension on your boat looks very nice (as does the boat). Thanks!

[CaptnJack]

Yeah I've trying setting the anchor but for some reason on gravel it never takes. I've used a Danforth on my old 34ft trawler and it always seemed to take alot of scope to start to set. Otherwise the flukes didn't seem to wanna catch. I'm surprised you guys are getting away with such short scope.

Danforths are cheap enough maybe I should give another one a go. Without a windlass I am limited to arm juice getting the thing aboard. Right now the chain is about 15lbs rode-lightchain-heavychain-anchor. So I would like to keep the anchor in the ~12lb range. For a Danforth that is probably too big for me to fit in my anchor locker. I could probably fit a 8-9lber though.

Thanks for the suggestions.

[Aquanautchuck]

Hey Jack. I have a 15.5 Zodiac also. It is a soft bottom and I dive with two anchors since there is rarely a body on the boat when I dive.

The first is a 12 lb Danforth clone with 10' of 1/4' chain that a friend gave me and he had used on his 28' cabin cruiser. The second is a 8 lb Danforth 10 lb clone with 8' of 5/16 chain.

I always set two anchors. If weather or current is mild I set the big one on the bow and the smaller one on the stern. (it also gives me two lines to come up with). If it is windy or heavy current I set both on the bow at about 330 and 30 degrees. I have almost never had the boat move set this way. Only one time did it drag about 5 ' and that time we got one of those sudden spring wind storms with winds over 30 mph. The bow was jumping up at least 6 feet like a horse.

I use a min of 2:1 road at all times or more and have never had a problem.

[boydski]

I'm surprised you guys are getting away with such short scope.

For 70' of water, I use 100' of line (+ the 25' of chain) and it seems to work very well.

For a Danforth that is probably too big for me to fit in my anchor locker. I could probably fit a 8-9lber though.

I probably should have clarified above that the reason I use the wee little anchor is that it is the only one that fits in my chain locker. The 14 lbs. anchor would actually work better, but is too big for the chain locker. I keep telling myself that I'm going to mount some anchor chocks on the bow for the larger anchor, but just haven't gotten around to it yet.

[CaptnJack]

All good info on what others are using. I got the 15lb Navy (for pretty cheap) cause Rob Holman uses one for his inflatable and from a sheer mass perspective it seems to work well for him. Not working for me though.

BTW the Polaris RIB with a 60hp can take 4 divers and 8 tanks (or even more if some are AL40s) and still does 20+ knots. Last weekend I had 3 divers, 3 sets of doubles, 4x AL80s, and 2x AL40s in there are we did 22kn at 4400rpm. Max was 25kn at 5200. Its an awesome boat.

[Dmitchell]

Without a windlass I am limited to arm juice getting the thing aboard. Right now the chain is about 15lbs

Thanks for the suggestions.

Aw, Come on that's nothing, we pull full king crab pots from 400' of water by hand, Do that a few times and anchors are easy. Before I broke down and bought the pot puller and windlass we'd go home with some sore muscles!

BTW the Polaris RIB with a 60hp can take 4 divers and 8 tanks (or even more if some are AL40s) and still does 20+ knots. Last weekend I had 3 divers, 3 sets of doubles, 4x AL80s, and 2x AL40s in there are we did 22kn at 4400rpm. Max was 25kn at 5200. Its an awesome boat.

That's great but I have HEAT

With that load you had I don't see any decrease in performance over an empty boat. Still 30mph (26 knots) - 46-4800rpm 8-9 gallons per hour. Add 1 more diver though an it drops big time. That's my prop issue. Fuel load matters too as I hold 85 gallons.


On your anchoring issue, I've noticed that especially with a light anchor if you let it fall to fast, the chain will sink faster than the anchor and can foul it. So make sure you are keeping tension on the line as it drops. This is why I hate having someone else drop my anchor. That and watching all that chain go over my rail because they just drop the anchor and let the chain run. ](*,)


Dave

[CaptnJack]

That's great but I have HEAT

Haha yeah I had lots oh heat and hot water in my 34ft trawler. But its was slow and a fuel hog.

With that load you had I don't see any decrease in performance over an empty boat. Still 30mph (26 knots) - 46-4800rpm 8-9 gallons per hour. Add 1 more diver though an it drops big time. That's my prop issue. Fuel load matters too as I hold 85 gallons.

I hold 12gals. Gives me a ~65mile range. I used it once already, 3 people, 2 sets of doubles, 2AL40s, 2 short Gavins. Deception Pass to Victroria area (56miles) and back used 9gals.

On your anchoring issue, I've noticed that especially with a light anchor if you let it fall to fast, the chain will sink faster than the anchor and can foul it. So make sure you are keeping tension on the line as it drops. This is why I hate having someone else drop my anchor. That and watching all that chain go over my rail because they just drop the anchor and let the chain run. ](*,)

Yeah my faric is getting a little worn from the the anchoring.

[mattwave]

Danforths are cheap enough maybe I should give another one a go. Without a windlass I am limited to arm juice getting the thing aboard.
Thanks for the suggestions.

Have you tried the Float with a ring trick for getting it up, my buddy swears by it, although I think he's about to put a windlass on the Hewes.
It needs to be a big float though.

[CaptnJack]

Danforths are cheap enough maybe I should give another one a go. Without a windlass I am limited to arm juice getting the thing aboard.
Thanks for the suggestions.

Have you tried the Float with a ring trick for getting it up, my buddy swears by it, although I think he's about to put a windlass on the Hewes.
It needs to be a big float though.

No I haven't. I've only seen them in the shops though, not in practice. One company is making a "one way" doohicky in place of the ring now. I have a fairly large ball fender, maybe I should add that to my repetoire (esp. for deep anchorages).