International Guild of Knot Tyers Forum

General => Practical Knots => Topic started by: vladimir3722 on December 28, 2012, 05:21:13 PM

Title: shear poles - what is it?
Post by: vladimir3722 on December 28, 2012, 05:21:13 PM
Hello all!

In ABOK #2803, 3317, 3377 shear poles are refered to. In dictionaries i found "shear pole derrick" and other meanings which i think is not what i seek.

Can anyone explain what this means? And why were they on the shrouds?

And what about "shroud doublings" in #3377?
Title: Re: shear poles - what is it?
Post by: SaltyCracker on December 29, 2012, 02:40:02 AM
Take a look at...
http://shipmodeling.net/vb_forum/threadedpost30799.html

Though not nautical, may also do a google or other search for sheer (or shear) lashing.
Title: Re: shear poles - what is it?
Post by: squarerigger on December 29, 2012, 09:04:04 AM
Hi Vladimir,
A sheer pole is a pole that is secured across the tops of the deadeyes that form the terminus of the shrouds.  It is there to prevent the deadeyes from twisting under load and is seized on to the shrouds in such a way that it is parallel to the sheer line of the ship (sheer line is the line the deck makes with the hull).  Sheer legs, when used in a combination like that, are poles that are usually much longer and are used two or three at a time, lashed together at one end and then used with a grommet or other loop to act as a hoist top for raising a mast or other heavy load from deck level.  Imagine a tripod arrangement, such that whatever you want to lift is shorter than the height of the underside of the top lashing around the three poles - hence a derrick or crane arrangement.  Here is Grog's animated knots page of sheer lashing to form sheer legs http://www.animatedknots.com/lashshear/index.php?LogoImage=LogoGrog.jpg&Website=www.animatedknots.com (http://www.animatedknots.com/lashshear/index.php?LogoImage=LogoGrog.jpg&Website=www.animatedknots.com)  Hope this helps!

SR
Title: Re: shear poles - what is it?
Post by: vladimir3722 on December 29, 2012, 05:28:03 PM
do a google or other search for sheer (or shear) lashing.

Thank you, SaltyCracker. I found the explanation under not "shear" but "sheer pole" and found russian explanation of this term.
Title: Re: shear poles - what is it?
Post by: vladimir3722 on December 29, 2012, 05:34:40 PM
A sheer pole is a pole that is secured across the tops of the deadeyes that form the terminus of the shrouds.  It is there to prevent the deadeyes from twisting under load and is seized on to the shrouds in such a way that it is parallel to the sheer line of the ship

..... Here is Grog's animated knots page of sheer lashing to form sheer legs http://www.animatedknots.com/lashshear/index.php?LogoImage=LogoGrog.jpg&Website=www.animatedknots.com (http://www.animatedknots.com/lashshear/index.php?LogoImage=LogoGrog.jpg&Website=www.animatedknots.com)

Thanks for explanation, squarerigger. Grog's site is very good.
Title: Re: shear poles - what is it?
Post by: vladimir3722 on December 29, 2012, 05:41:04 PM
And what about "shroud doublings" in #3377? Are doublings double parts of shroud? But on the picture i see sheer pole seized in to the single parts.
Title: Re: shear poles - what is it?
Post by: SS369 on December 29, 2012, 06:05:29 PM
Hi Vladimir.

Not a specific answer, but, I want to share two links that will possibly bring you knowledge about the specific parts of sailing ships.
There is a lot of information!

http://www.hnsa.org/doc/luce/index.htm (http://www.hnsa.org/doc/luce/index.htm)
http://www.hnsa.org/doc/steel/index.htm (http://www.hnsa.org/doc/steel/index.htm)

I hope this helps and you enjoy.

SS
Title: Re: shear poles - what is it?
Post by: squarerigger on December 30, 2012, 08:58:02 PM
Hi again Vladimir,

Sorry, I missed telling about the doublings.  This is the section of the shrouds which is taken around the dead-eye to allow it to be laid alongside itself (and be seized there to prevent its movement) and to which the sheer pole is lashed, as Ashley illustrates in his excellent drawing (#3377). It is not mathematically doubled, it is just laid around to meet itself.  An old English term 'doubling' is from 1633 (according to the OED), referring to the act of bending or turning something, as the shroud is bent or turned around the dead-eye and is hence 'doubled' in the parlance of the sailors of that time.

 :)

SR
Title: Re: shear poles - what is it?
Post by: vladimir3722 on January 01, 2013, 12:13:26 PM
Thank you, squarerigger, for the help.

Sure, 17-century English is not the same as modern English. But ABOK is the excellent book which i want to understand and make practical use of it. There is no book in Russian like this one.