IMO - If one of the #'s 1 relates to scope... then for scope to exist there must be an angle of rode from bow to anchor. Otherwise... if rode is 100% plumb off bow to anchor there exists "Zero" scope. Thus 1:0!
Fortress Anchor Retrival
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IMO - If one of the #'s 1 relates to scope... then for scope to exist there must be an angle of rode from bow to anchor. Otherwise... if rode is 100% plumb off bow to anchor there exists "Zero" scope. Thus 1:0!
Anchor Rode / Scope
Art, Eric...
Maybe a picture will help. Right out of Chapmans.
This is why we mark the rode and it's easy to determine what the rode L is and you get D form depth finder + known ht of bow for your vessel.
Interesting how many folks get things stuck in their mind.
I've had folks explain to me that Red Right Return meant Keep Red to Port When return TO the sea.. and they were absolutely sure that's what it meant.
Surprised they haven't had some serious problems.
Art, Eric...
Maybe a picture will help. Right out of Chapmans.
This is why we mark the rode and it's easy to determine what the rode L is and you get D form depth finder + known ht of bow for your vessel.
Interesting how many folks get things stuck in their mind.
I've had folks explain to me that Red Right Return meant Keep Red to Port When return TO the sea.. and they were absolutely sure that's what it meant.
Surprised they haven't had some serious problems.
Attachments
Art...IMO - If one of the #'s 1 relates to scope... then for scope to exist there must be an angle of rode from bow to anchor. Otherwise... if rode is 100% plumb off bow to anchor there exists "Zero" scope. Thus 1:0!
I think that's where folks get hung up...
The ratio of scope is not an angle - it can be converted to an angle - see post #23 above -
"Scope of the Rode" is also NOT rise over run as in "slope of a road"(no pun intended) or stairs.
It is the the hypotenuse (L of rode) over rise (depth to bow)
Don - I feel that "0" rode angle = "0" scope. "0" angle simply can't = a scope of 1. To me 1:1 means there is some scope in play. At 100% plumb off bow there is NO scope in play... which means in that instance that scope does Not At All Exist... therefore it has to be 1:0 ;i.e., "0" scope.
But anyway - Nice of Chapman to put profile of my Tollycraft on the page!
Don - I feel that "0" rode angle = "0" scope. "0" angle simply can't = a scope of 1. To me 1:1 means there is some scope in play. At 100% plumb off bow there is NO scope in play... which means in that instance that scope does Not At All Exist... therefore it has to be 1:0 ;i.e., "0" scope.
But anyway - Nice of Chapman to put profile of my Tollycraft on the page!
Art...
As with any discussion on TF you are certainly entitled your your opinion
I'm not sure if your interpretation of the ratio is Horiz run : Vertical depth?
If so per your interpretation "0" = 0:1 = vertical rode and 1:1 = 45* angle
and in reality it doesn't make that much difference when you are talking "normal" working scopes of 5:1 or 7:1 they differ greatly at the low end.
The difference in the angle between Chapmans (& others) and your interpretation are very small until you get to small scopes
Chapmans can never go below "1" where your interpretation goes to "0"
Art...
As with any discussion on TF you are certainly entitled your your opinion
I'm not sure if your interpretation of the ratio is Horiz run : Vertical depth?
If so per your interpretation "0" = 0:1 = vertical rode and 1:1 = 45* angle
and in reality it doesn't make that much difference when you are talking "normal" working scopes of 5:1 or 7:1 they differ greatly at the low end.
The difference in the angle between Chapmans (& others) and your interpretation are very small until you get to small scopes
Chapmans can never go below "1" where your interpretation goes to "0"
Equally
and 
Nomad Willy
Guru
Don I understood it weeks ago .. Just don't like it.
Dosn't matter .. it is what it is.
I went straight to Chapman and it's clear there. We are just trying to use the horizontal distance and not the length of the rode. At longer scopes there's little difference but at short scopes the "scope" of it all seems more clear to me using distance and not rode length in the function of relating to anchoring scope. But when talking to other people one muct use the language that is vogue or you won't comunicate well.
And I see why rode length is used in that it is much much more easily determined on the fly where one needs to know what his relative scope is. We all feed out "X" # of feet of line or chain but how are we to measure the distance from the bow to the anchor?
Dosn't matter .. it is what it is.
I went straight to Chapman and it's clear there. We are just trying to use the horizontal distance and not the length of the rode. At longer scopes there's little difference but at short scopes the "scope" of it all seems more clear to me using distance and not rode length in the function of relating to anchoring scope. But when talking to other people one muct use the language that is vogue or you won't comunicate well.
And I see why rode length is used in that it is much much more easily determined on the fly where one needs to know what his relative scope is. We all feed out "X" # of feet of line or chain but how are we to measure the distance from the bow to the anchor?
That is the way I have always heard scope defined, be it by the USCG Auxilliary boating course my wife and I took back in the 1980s to the conversations in the marine supply store in our harbor where we bought our new chain rode to discussions about anchoring in the boating club we belong to.
A scope of one to one would be thirty feet of rode out and thirty feet to the bottom. A scope of two to one would be sixty feet of rode out and thirty feet to the bottom, and so on. Very basic, very simple.
Nomad Willy
Guru
Marin,
Yes simple in this case is an advantage in that it makes it more useable.
I'm fairly good at making things more complex than they are.
Yes simple in this case is an advantage in that it makes it more useable.
I'm fairly good at making things more complex than they are.
Eric
Everyone can easily measure the bow ht from the water and file this away as a constant or leave a sticky at the helm. When getting ready to anchor it's easy to get the depth from a depth finder and simply add the constant bow ht.
Then all you have to do is multiply the sum by the "scope" you intend to use for anchoring...
5:1 (lunch hook) 7:1 "normal" conditions o'nite 10:1 storm anchoring...
rather straight forward - and deploy that L of rode.
I would ask... how do you calculate the L of rode to deploy if you want a horizontal distance of 7 x the depth? - you'd need a Trig table & calculator
Or how do you determine the horizontal distance from your bow to the anchor position?
But let's not
use whatever works for you
jleonard
Guru
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- Jun 25, 2008
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Scope = Done by Eye Baby! After decades boating and anchoring hundreds of times... depth from sounder plus bow height establishes bow nose to bottom length... Eye sight and "feel of the deal" establishes scope. For me anyway! No matter how the ratio may be stated in numbers
Pgitug
Guru
Reading your posts is like watching a new release of Big Bang Theory. I just can't quite figure out which one is Sheldon, Leonard and Howard. You guys are way over my head.
OP
OP
timjet
Guru
- Joined
- Apr 9, 2009
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Me too.
But with some real world experience now I think I've figured this out. Mud is the predominant bottom on the Chesapeake so a Fortress is a good choice if adjusted for mud. I don't set the anchor hard, just idle reverse on one engine. When retrieving I get the rode vertical and just let the boat and anchor work their way loose, maybe a minute or so.
I've also found not as much scope is needed with this anchor in mud. That's nice in a crowded anchorage.
