Rigging a small boat for diving

[Braunbehrens]

Groundhog246 once bubbled...


Are you talking about breaking the anchor loose? Or pulling in all the rode?

The method I describe does both.

Here are some links describing it:

http://www.westmarine.com/webapp/wc...0001&classNum=186&subdeptNum=11205&storeNum=5

http://www.newsherald.com/articles/2001/11/25/wf112501a.htm

The question is, does it mess up the reef to use this method?

 

[Stone]

Braunbehrens once bubbled...
Just to clarify. You hang a ball on the anchor rode and motor towards the anchor. The ball goes down somewhat and the anchor ends up popping up attached to the ball.

So you say that you use this method and you have never hooked another part of the wreck or reef?

If this is true then it is good news indeed. I always worry that the anchor might rake across the reef with this method, but maybe it goes straight up.

Our "reefs" are little more than limestone out-croppings, usually not more than a dozen feet wide and a couple of hundred feet long. We always go down the anchor line, both to see if the anchor is set, and to determine how we are lined up on the "reef". Most of the year the wind is out of the south, i.e., S, SE, or SW, so we head into the wind, find the bottom structure, pass it a little and drop the hook. In this case, we can head the boat straight for the anchor without worrying about damaging the "reef".

When using the anchor ball, even the chain pulls through the ring, leaving flukes of the Danforth hooked in the ring three feet from the surface.

Let's say I'm laying dead north of a 200 ft barge that runs east/west. I don't have to run over the barge to pull the hook. I motor toward the barge, but head east or west which still breaks the anchor free.

I have never hung up on reef or wreck (in about 100 dives).

Groundhog246 once bubbled...
It's not currents, or even waves I particularly worry about, it's wind.

It is the wind that concerns me the most as well, especially after reading the comments on the Danforth.

Have you boating experience prior to that year? Or taken any courses? I haven't been diving for all that long, but I've been around boats since I was a kid and owned several on and off for 25 years. If your chain is in a clump, it doesn't sound like you've even "set" the anchor, just dumped the whole works off the bow. I really hope a squall does not catch you in the water, or you are likely to surface and no see your boat.

I've been boating (sail and power) off and on for over 30 years. My comment about the chain in a clump was meant to indicate that very often, there is not enough wind or current to even take the slack out of the rode. When this is the case, I set the anchor by hand

 

[Groundhog246]

Braunbehrens once bubbled...


The method I describe does both.

Here are some links describing it:

http://www.westmarine.com/webapp/wc...0001&classNum=186&subdeptNum=11205&storeNum=5

http://www.newsherald.com/articles/2001/11/25/wf112501a.htm

The question is, does it mess up the reef to use this method?

Short answer, don't know. Some confusion though. West Marine descirbes the ball as descending to the anchor and then floating it up????

Newsherald give the impression that the ball stays afloat and the rode is pulled through the ring.

Wonder how fast you have to go to make it work? I've a max of about 6 knots under power.

I don't see it helping at all if you've got a fluke hooked under something. Either the fluke is going to give (a bent fluke, even a slight bend is a frequent cause of future problems getting an anchor to set), or the object (reef, wreck, rock, ....) is going to give (break).

 

[Groundhog246]

Stone once bubbled...
I've been boating (sail and power) off and on for over 30 years. My comment about the chain in a clump was meant to indicate that very often, there is not enough wind or current to even take the slack out of the rode. When this is the case, I set the anchor by hand

OK, I understand to a point. Most of my anchoring (still) is for overnight stays and we don't usually dive the anchor (although it's often less than 20 ft deep and we can and do, usually dinghy over and look). Normal anchoring technique is to pick your spot, lower the anchor till it touches down, let out sufficient rode for the depth and back down until the anchor bites in, then hard on with the engine to set the anchor. If the anchor will not hold with full reverse, than it's not a "good" set. With this technique, the cahn is never in a "clump". I have seen times, when anchored for a while in shifty winds where the chain ends up zig zagged across the bottom and a couple of time when the wind has done a 360, the chain lying in a circle around the anchor and the anchor never moved.

 

[Stone]

Groundhog246 once bubbled...

West Marine describes the ball as descending to the anchor and then floating it up????

Newsherald give the impression that the ball stays afloat and the rode is pulled through the ring.

My anchor ball stays afloat until the chain pulls through the ring. When the ball submerges, I know the anchor is up.

Wonder how fast you have to go to make it work? I've a max of about 6 knots under power.

6 knots is fast enough for my ball.

I don't see it helping at all if you've got a fluke hooked under something. Either the fluke is going to give (a bent fluke, even a slight bend is a frequent cause of future problems getting an anchor to set), or the object (reef, wreck, rock, ....) is going to give (break).

If you're fishing, you could run into trouble. If you're diving, you should always be able to know the status of your anchor and be able to move it if necessary.

The one place we could run into trouble near Destin is on the "Bridge Rubble". The rubble is not all in one place. Theoretically, you could pull the anchor in a direction that looks like all sand, but hook a small section of rubble (if the anchor drags more than a few feet).

I am curious as to whether the anchor pulls straight up or drags a certain number of feet.

 

[Stone]

Normal anchoring technique is to pick your spot, lower the anchor till it touches down, let out sufficient rode for the depth and back down until the anchor bites in, then hard on with the engine to set the anchor.

A lot of our diving is on small deep sites. Cement culverts, bridge rubble, and M60 tanks. As soon as we get a show on the bottom finder, we drop the anchor (scope already measured) so as to have the anchor hit as close to the target as possible. If the vis is bad, the anchor needs to be dead on, or all you see is sand. If there is enough wind or surface current to move the boat, we drift (or sometime I reverse) until the anchor sets (checking by feel and GPS).

Obviously, different techniques are required for different conditions.

 

[Braunbehrens]

Groundhog246 once bubbled...
Newsherald give the impression that the ball stays afloat and the rode is pulled through the ring.

Wonder how fast you have to go to make it work? I've a max of about 6 knots under power.

I don't see it helping at all if you've got a fluke hooked under something. Either the fluke is going to give (a bent fluke

The ball may submerge somewhat, but it doesn't go down to the anchor. If it did, it would not have enough flotation anymore to lift the anchor, due to compression.

You don't need or want to go too fast.

Since you are going back over the anchor you are now pulling it 180º from the direction it set. Most of the time it comes right out.

Of course there are always the occasional problems with all these methods.

If your anchor gets bent then it was no good to begin with. A Fortress 14 pounds will hold 4,650 pounds before it breaks and a 33 pound Bruce will hold 18,500. A 27 pound regular Danforth will hold 5,700 pounds.

I don't have figures for the lighter anchors, except the 6 pound Fortress which holds 2000 pounds.

In these test the Fortress seems to win out by a large margin, despite it's smaller weight.

 

[Groundhog246]

Braunbehrens once bubbled...
If your anchor gets bent then it was no good to begin with. A Fortress 14 pounds will hold 4,650 pounds before it breaks and a 33 pound Bruce will hold 18,500. A 27 pound regular Danforth will hold 5,700 pounds..

I have no idea what it would take to bend a Bruce type, more force than I think I could generate. With the Fortress or Danforth, the rated loads are those it will hold with both flukes set and appropriate scope. However, if you hook one fluke under something, get directly over the top (rode straight up and down) and either apply force with a winch or via engine power to try and break it loose, you can quite easily bend a fluke or the bar the flukes mount on. I know, because I've seen it done more than once. If it does happen, replace the anchor, it'll never be quite right again and a new anchor is a lot cheaper than a new boat or boat repairs.

In the case of all anchors, it's not weight that determines holding power, but how well they can dig in. In mud, nothing holds all that well, a fortress angled for mud is better than most, in sand a Danforth or Fortress is good once it's set and as long as you don't pull it sideways, in which case thay have a habit of not re-setting, in gravel I've never found a Danforth or fortress to set and a Bruce or a plow will set, but not hold particularly well (not much works well in gravel, slight edge to a plow). In rocky areas, an old fashioned Fishermans anchor +-) is an excellent choice (at least until you want it back).

Anchoring is indeed a question with no one "right" answer.

 

[Stone]

Here is a link (pictures, too) on How to Use an Anchor Ball.

This is how I learned to do it, because you don't want to wrap the rode around your prop.

 

[Braunbehrens]

THanks for that url, it's great to have a graphic.

The figures I gave are for how much load it takes to break or bend the anchor, both flukes held near the tip. It was a test done in a specially designed machine. they are NOT holding test for seafloor conditions, but rather how much force it takes to bend the flukes or break them.

I was amzed at how much the Fortress can take, more than the steel!