SailNet Community - Reply to Topic

   Search Sailnet:

 forums  store  


Quick Menu
Forums           
Articles          
Galleries        
Boat Reviews  
Classifieds     
Search SailNet 
Boat Search (new)

Shop the
SailNet Store
Anchor Locker
Boatbuilding & Repair
Charts
Clothing
Electrical
Electronics
Engine
Hatches and Portlights
Interior And Galley
Maintenance
Marine Electronics
Navigation
Other Items
Plumbing and Pumps
Rigging
Safety
Sailing Hardware
Trailer & Watersports
Clearance Items

Advertise Here






Go Back   SailNet Community > Skills and Seamanship > Seamanship & Navigation > Duncan Loop in lieu of eye splice or bowline?
 Not a Member? 

Seamanship & Navigation Forum devoted to seamanship and navigation topics, including paper and electronic charting tools.


Thread: Duncan Loop in lieu of eye splice or bowline? Reply to Thread
Title:
  

By choosing to post the reply below you agree to the rules you agreed to when joining Sailnet.
Click Here to view those rules.

Message:
Trackback:
Send Trackbacks to (Separate multiple URLs with spaces) :
Post Icons
You may choose an icon for your message from the following list:
 

Register Now

In order to be able to post messages on the SailNet Community forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
Please note: After entering 3 characters a list of Usernames already in use will appear and the list will disappear once a valid Username is entered.
User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.



Click here to view the posting rules you are bound to when clicking the
'Submit Reply' button below


Additional Options
Miscellaneous Options

Click here to view the posting rules you are bound to when clicking the
'Submit Reply' button below


Topic Review (Newest First)
01-02-2012 06:46 PM
dave22q looks like slip knot to me also. does have benefit of not binding/ easy to loosen as well as quick and easy to tie. will jam on a teardrop thimble and i've never seen a round one.

According to the U.S. Coast Guard in their Boat Crew Seamanship Manual common knots loose much of the line's strength. The following table is from the above manual.

Knots or Splice Percent of Line
Breaking Strength Lost Percent of Line,Breaking Strength Remaining
Square 46 54
Bowline 37 63
Two Bowlines (Eye in Eye) 43 57
Becket Bend 41 59
Double Becket Bend 41 59
Round Turn 30-35 65-70
Timber Hitch 30-35 65-70
Clove Hitch 40 60
Eye Splice 5-10 90-95
Short Splice 15 85
01-02-2012 03:18 PM
nedun Corrected Duncan Loop:
I am trying to correct some improper illustrations found in many web-sites and several publications that show how to tie a fishing knot that is variously known as a Duncan Loop, Uni-Knot or Grinner.
In Geoff Wilson's “Complete Book of Fishing Knots & Rigs” the illustration of the “Duncan Loop” is shown improperly since the initial loop is formed on the standing line side of the hook eye.
This improper illustration of the Duncan loop is a non-slip loop and to my knowledge has no name, it may or may not have similar breaking strength as the Duncan loop depending on how it is set and what type of fishing line is used.
When the initial loop is formed in the tag end portion of the line after passing through the hook eye it can form a Duncan Loop if properly set.
In the same frame of the book, the illustration immediately below labeled “Uni-Knot” is a proper illustration of the Duncan Loop although the snugging and final setting are not shown. The Uni-Knot is a later renamed copy of the original Duncan Loop.
If pulled down and set properly the final configuration of the Duncan Loop, Uni-Knot or Grinner are all the same.

I believe that some of the confusion lies in the manner of which these knots are pulled down and set after the last wrap with the tag end is passed through the initial loop. In my knot and the Uni the tag end is pulled in the same direction as the standing line with sufficient force to allow the wraps to wind back over themselves to form a neat spiral over the standing and tag lines, like a nail knot tied back over on the line itself. If this is not done the knot will not fold over and therefore form knots that differ in their final configuration and strength.

I can help clarify some of the difficulties encountered when tying this knot in ropes and lines used for boating. Norman
04-06-2011 06:37 PM
SlowButSteady
Quote:
Originally Posted by AdamLein View Post
Aside from my creative syntactical choices, I'd say they are isomorphic
Yeah, I had my wrong glasses on when I originally read your post, and missed the punctuation (its hell getting old, but it sure beats the only known alternative).

Quote:
Originally Posted by AdamLein View Post
There ya' go.

I have a similar comic I use to illustrate the need for multiple comparison correction.
04-06-2011 06:20 PM
AdamLein
Quote:
Originally Posted by SlowButSteady View Post
OK, which is worse: "My battery's have a "capacity" of 170 amp's" or "The harbor isn't far, only about 3 knots from here" ????
Aside from my creative syntactical choices, I'd say they are isomorphic

also: xkcd: Significant
04-06-2011 05:31 PM
SlowButSteady
Quote:
Originally Posted by AdamLein View Post
And I thought I was a stickler for presentation :P
Well, as I said, you asked.

Quote:
Originally Posted by AdamLein View Post
Then maybe it was okay that they didn't include error bars
Nope. The author (with the title of "Technical Director", no less) is presenting means. A mean is an estimation of some sort of theoretical value, in this case breaking strength. It is NEVER acceptable to present a mean w/o an estimation of the error (e.g., variation) about that mean.

Quote:
Originally Posted by AdamLein View Post
Anyway if that sort of thing is like fingernails on chalkboards, try this one on for size: My battery's have a "capacity" of 170 amp's.
My ears!!! My ears!!!

OK, which is worse: "My battery's have a "capacity" of 170 amp's" or "The harbor isn't far, only about 3 knots from here" ????
04-06-2011 05:19 PM
AdamLein
Quote:
Originally Posted by SlowButSteady View Post
- "Figures" 1, 2, and 3 are tables, not figures
- Standard Errors (in addition to Standard Deviations) should be given, as we are interested in a comparison of means
- Units should be SI, not American/English customary (however, engineers never seem to understand this)
- The Abstract is a disaster (don't get me started)
- The Equipment and Methods sections (essentially analogous to a "Materials and Methods" section of a standard format scientific paper) should be expanded with greater detail
- Figures (and Tables) are presented but not cited in the text
...
- Figures are inconsistent as to orientation (strength is scaled horizontally in Figs. 4 - 7 and vertically in Fig. 8)
- Fig. 7 is redundant, it simply repeats means presented in Figs. 4 - 6
- All of the figures present means, yet none have error bars (SD or SE)
- Differences in knot breaking strength, as it relates to material strength, are discussed (albeit briefly) without any tests of statistical significance
- And (one of my pet peeves), the word "data" is the plural of "datum". Therefore, "the data was" is grammatically somewhat akin to saying, "the cows was," (and sounds like fingernails on a chalkboard to Yours Truly)
And I thought I was a stickler for presentation :P

Quote:
- Figure 8 is presented as if the different knots have some ordinal relationship, which they do not.
Okay, you have a point with this one. That's really grating.

Quote:
As to the small sample size; it's actually probably OK for such a study. There variation about the means here appear small enough that increasing the replication would probably not change the over-all results enough to worry about.
Then maybe it was okay that they didn't include error bars

Anyway if that sort of thing is like fingernails on chalkboards, try this one on for size: My battery's have a "capacity" of 170 amp's.
04-06-2011 03:33 PM
Boasun This is a mere minor detail to me..
Seeing that I've been splicing sense Norah was a cabin boy. I'll just go ahead and splice it. And if the line is solid single braid I will put a couple of seizings on it and not worry about minor details.
04-06-2011 03:30 PM
LandLocked66c
Quote:
Originally Posted by SlowButSteady View Post
When I teach BioStatistics I spend about two and a half lectures (almost an entire week of class) on data presentation, so I could give you a pretty long list of the errors made in the presentation cited.

But, to start (since you ask):

- "Figures" 1, 2, and 3 are tables, not figures
- Standard Errors (in addition to Standard Deviations) should be given, as we are interested in a comparison of means
- Units should be SI, not American/English customary (however, engineers never seem to understand this)
- The Abstract is a disaster (don't get me started)
- The Equipment and Methods sections (essentially analogous to a "Materials and Methods" section of a standard format scientific paper) should be expanded with greater detail
- Figures (and Tables) are presented but not cited in the text
- Figure 8 is presented as if the different knots have some ordinal relationship, which they do not.
- Figures are inconsistent as to orientation (strength is scaled horizontally in Figs. 4 - 7 and vertically in Fig. 8)
- Fig. 7 is redundant, it simply repeats means presented in Figs. 4 - 6
- All of the figures present means, yet none have error bars (SD or SE)
- Differences in knot breaking strength, as it relates to material strength, are discussed (albeit briefly) without any tests of statistical significance
- And (one of my pet peeves), the word "data" is the plural of "datum". Therefore, "the data was" is grammatically somewhat akin to saying, "the cows was," (and sounds like fingernails on a chalkboard to Yours Truly)

As to the small sample size; it's actually probably OK for such a study. There variation about the means here appear small enough that increasing the replication would probably not change the over-all results enough to worry about.
Wow, I feel dumb after reading this! Good stuff!
04-06-2011 03:02 PM
SlowButSteady
Quote:
Originally Posted by AdamLein View Post
What was wrong with their representation? I mean, if you're going to complain about something, why not the tiny sample size?
When I teach BioStatistics I spend about two and a half lectures (almost an entire week of class) on data presentation, so I could give you a pretty long list of the errors made in the presentation cited.

But, to start (since you ask):

- "Figures" 1, 2, and 3 are tables, not figures
- Standard Errors (in addition to Standard Deviations) should be given, as we are interested in a comparison of means
- Units should be SI, not American/English customary (however, engineers never seem to understand this)
- The Abstract is a disaster (don't get me started)
- The Equipment and Methods sections (essentially analogous to a "Materials and Methods" section of a standard format scientific paper) should be expanded with greater detail
- Figures (and Tables) are presented but not cited in the text
- Figure 8 is presented as if the different knots have some ordinal relationship, which they do not.
- Figures are inconsistent as to orientation (strength is scaled horizontally in Figs. 4 - 7 and vertically in Fig. 8)
- Fig. 7 is redundant, it simply repeats means presented in Figs. 4 - 6
- All of the figures present means, yet none have error bars (SD or SE)
- Differences in knot breaking strength, as it relates to material strength, are discussed (albeit briefly) without any tests of statistical significance
- And (one of my pet peeves), the word "data" is the plural of "datum". Therefore, "the data was" is grammatically somewhat akin to saying, "the cows was," (and sounds like fingernails on a chalkboard to Yours Truly)

As to the small sample size; it's actually probably OK for such a study. The variation about the mean here appear small enough that increasing the replication would probably not change the over-all results enough to worry about.
04-06-2011 01:07 PM
AdamLein
Quote:
Originally Posted by SlowButSteady View Post
Now, if they would just have presented their stats properly....sigh....well, at least it's a start.
What was wrong with their representation? I mean, if you're going to complain about something, why not the tiny sample size?
This thread has more than 10 replies. Click here to review the whole thread.

 
Posting Rules
You may post new threads
You may post replies
You may post attachments
You may edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On


All times are GMT -4. The time now is 03:42 AM.

Add to My Yahoo!         
Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
SEO by vBSEO 3.6.1
(c) Marine.com LLC 2000-2012

The SailNet.com store is owned and operated by a company independent of the SailNet.com forum. You are now leaving the SailNet forum. Click OK to continue or Cancel to return to the SailNet forum.