anchoring

[pgpg5860]

Hi, I'm new at the baoting scene and if anyone can give me some clairification it would be a big help. When anchoring I've noticed a lot of boats pull up and drop the anchor straight down then back up about 20 -30 feet, (40' of water) the rope/chain then looks like it's at almost straight up and down. I haven't seen them move during the night except for a small swing. Is this safe? Will it hold me if the wind picks up?
thanks in advance for your help

 

[dmcb]

Re: anchoring

There may be more to it than what you see. All chain for example will look straight down but its the scope that counts.
I did this for another site but you might get some pointers.
Having the amount of scope I suggest may not always be possible but I anchor in small coves with rocky shores and slipping anchor is just not an option.
Remember this just my views and is not the only successful way.

"
http://baylinerownersclub.org/forum/showthread.php?p=71599#post71599"
Doug

 

[Chris1956]

Re: anchoring

Normally you want to put out 5-7 times the depth of the water to assure the anchor has enough "scope" to hold well. A 5 foot piece of chain between the anchor and the line also helps the anchor hold better. it is also good to pay out the anchor line, cleat it off and back down on the anchor to set it.

 

[Boatist]

Re: anchoring

Is it safe? Short answer is no. Of course it depends on what type anchor you have. To be safe you should use normal scope 7 to 1. So 40 feet of water you need 7 times 42 or 294 of anchor line.

Most of the time in nice calm weather 3 to 1 is good but if no one on board is on watch then need to go to 7 to 1.
With a Danforth type anchor and a 3 to 1 scope with some chain it will usually hold. If the wind current and Seas Pick up during the night then you could find yourself draging the anchor. With Chain near the anchor in calm weather and current the chain will hold the anchor line down on the bottom and light pulls cause the anchor to dig in. If the wind current or seas pick up and the load on the anchor is greater the line will pull hard on the anchor and the anchor line the chain and the anchor shank will point striaght at the tie point on the boat. With a short scope the shank pointing at the boat tie point means the flutes will also point up and instead of digging deeper under load they will not dig in at all and just drag lightly on the bottom.

 

[SteveRay]

Re: anchoring

Is it safe? Short answer is no. Of course it depends on what type anchor you have. To be safe you should use normal scope 7 to 1. So 40 feet of water you need 7 times 42 or 294 of anchor line.
QUOTE]


Just to clarify boatist's calculations a bit, when you take into account the depth of the water your in for your scope calculation you should also add in the height of you tie off point to the depth calculation.
For example if you are in the 40 feet of water as boatist said, he added 2 extra feet to accomodat the height of the boat at the bow windlass.
Usually not going to make a huge difference but figured I would elaborate

 

[pgpg5860]

Re: anchoring

thanks for the inputs, we use a 16lb Bruce anchor with 30' of chain then we have 650' of rope. When we swing around the anchor with the tide can you break free or will you stay securely anchored if we use the 7 - 1 ratios?
thanks

 

[dmcb]

Re: anchoring

You haven't mentioned what all this is attached to.
In other words, the missing thing is the size of your boat.
While the type of bottom makes a difference, I used that size anchor on a 28 foot boat and it never has slipped.
That is in about 5 years use and we spend the summer on the hook so it represents a lot of days.
However on my 38 foot boat I snagged a log and after 2 days the log came up with the anchor. Perfectly ballanced on the anchor.
So there is no way you can be sure it will always hold. But with the proper anchor and scope you can cut down on failures.
One other thing. Most gps has a drift alarm, anchor alarm, or whatever they call it on their model.
Set that and it will alert you if you move.
Also many depth sounders have an alarm. Set the depth for something different than you are in and if you move that will also alert you.
Of the two, the gps is your best bet however.
Doug

 

[pgpg5860]

Re: anchoring

Sorry DMCB, the boat is a 24' Bayliner and the bottom is usually mud/sand or shells/gravel.

 

[dmcb]

Re: anchoring

Well I never anchored in shells and/or gravel but I think you have one of the best setups you can get.
I think any anchor would have to get below the shells to hold.
Now do you have your anchor rode marked so you know how much you have out?
If not there are little flags available with different numbers that you can weave in the rope.
Or you might use paint. That is the usual way for chain.
You have a lot of line. Do you need that much?
Doug

 

[pgpg5860]

Re: anchoring

We've market the rope every 100' with shrink wrap, the type used in electrical work. When fishing for Halibut we're in 300' of water so to anchor I have to throw it all out or it pulls loose, also sometimes we're in +70' of water at night with a 20' tide. The anchoring in shells/gravel was pretty hard to do it took a long time to get a set I was comfortable with. When you swing with the tide can you pull free even with the correct scope?
thanks

 

[dmcb]

Re: anchoring

Ya I guess you need it all.
Wow, that is a lot of water.
I think I am in deep water at 40 feet.
Doug