Author Topic: Need a knot for specific application  (Read 4562 times)

-bowfreak-

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Need a knot for specific application
« on: July 11, 2012, 04:11:06 PM »
I am looking for a knot that I can that will allow me to maintain tension without backsliding (I am not sure of the terminology but losing tension during tying).  I have a rope that is fixed on one end.  I want to attach the loose end to an object that moves toward the fixed end when working.  The object at rest will keep the line tight but while working will become slack.  How can I do this?  I have played around with some different knots but can't come up with anything with my limited experience to make this work.  Thanks for the help in advance.  This is a really cool resource you guys have going here. 

roo

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Re: Need a knot for specific application
« Reply #1 on: July 11, 2012, 04:39:48 PM »
I am looking for a knot that I can that will allow me to maintain tension without backsliding (I am not sure of the terminology but losing tension during tying).  I have a rope that is fixed on one end.  I want to attach the loose end to an object that moves toward the fixed end when working.  The object at rest will keep the line tight but while working will become slack.  How can I do this?  I have played around with some different knots but can't come up with anything with my limited experience to make this work.  Thanks for the help in advance.  This is a really cool resource you guys have going here.
See if some form of this might work:
http://notableknotindex.webs.com/Versatackle.html
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Sweeney

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Re: Need a knot for specific application
« Reply #2 on: July 11, 2012, 05:36:43 PM »
I am looking for a knot that I can that will allow me to maintain tension without backsliding (I am not sure of the terminology but losing tension during tying).  I have a rope that is fixed on one end.  I want to attach the loose end to an object that moves toward the fixed end when working.  The object at rest will keep the line tight but while working will become slack.  How can I do this? 

It would help if you were a bit more specific about what you are doing - for example from your description it could be something like ropemaking where the rope shrinks as it is laid up causing movement toward the fixed end. That may not be the case but it's not clear whether you are trying to maintain continuous tension or wish to reintroduce tension periodically as the object at rest moves.

Barry

Dan_Lehman

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Re: Need a knot for specific application
« Reply #3 on: July 11, 2012, 08:32:51 PM »
Quote
I want to attach the loose end to an object that moves toward the fixed end when working.
The object at rest will keep the line tight but while working will become slack.

I don't understand this : what are you saying, what do you want?
(It sounds as though you're seeking a magical knot that somehow
will take up the slack to maintain tension when the moving part
moves towards the fixed end!)

Perhaps you mean that you will be present and able
to adjust the knot to continually maintain tension
(some sag; user-adjustment to re-tension; ... repeat).
In such a case, some sort of friction hitch might work, where
one will re-tighten by pulling line through the hitch (possibly
tied in a separate piece of cordage to whichever end of things
--fixed or moving-- is handier).


--dl*
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-bowfreak-

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Re: Need a knot for specific application
« Reply #4 on: July 11, 2012, 08:55:34 PM »
Quote
I want to attach the loose end to an object that moves toward the fixed end when working.
The object at rest will keep the line tight but while working will become slack.

I don't understand this : what are you saying, what do you want?
(It sounds as though you're seeking a magical knot that somehow
will take up the slack to maintain tension when the moving part
moves towards the fixed end!)

Perhaps you mean that you will be present and able
to adjust the knot to continually maintain tension
(some sag; user-adjustment to re-tension; ... repeat).
In such a case, some sort of friction hitch might work, where
one will re-tighten by pulling line through the hitch (possibly
tied in a separate piece of cordage to whichever end of things
--fixed or moving-- is handier).


--dl*
====

OK.  I will take pics to show you guys tonight but this knot would be attached to the upper limb of a compound bow.  The other end of the cord is attached to the arrow rest.  While the bow is at brace (undrawn) the rope is tight and keeps the rest flat out of the way of the arrow as it passes through the bow.  As the bow is drawn, the limbs flex (cord is tied to top limb limb) and at full draw the cord will be slack which allows the rest to rise and hold the arrow in place.  When the bow is fired the arrow rest is driven out of the way to allow the arrow to pass cleanly.

Normally the cord is attached to the upper limb by tying and THEN it is attached to the arrow rest.  Cord would be pulled tight through the arrow rest and a set screw is then tightened to keep tension at brace.  What I am trying to do is attach it the opposite way at I don't like the set screw setup.  I want to attach the cord to the rest tie a knot so the cord can't be pulled back through and then attach to the upper limb like I described above.

I will get you guys some pics or a video posted  for clarification.

roo

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Re: Need a knot for specific application
« Reply #5 on: July 11, 2012, 09:05:35 PM »
OK.  I will take pics to show you guys tonight but this knot would be attached to the upper limb of a compound bow.  The other end of the cord is attached to the arrow rest.  While the bow is at brace (undrawn) the rope is tight and keeps the rest flat out of the way of the arrow as it passes through the bow.  As the bow is drawn, the limbs flex (cord is tied to top limb limb) and at full draw the cord will be slack which allows the rest to rise and hold the arrow in place.  When the bow is fired the arrow rest is driven out of the way to allow the arrow to pass cleanly.

Normally the cord is attached to the upper limb by tying and THEN it is attached to the arrow rest.  Cord would be pulled tight through the arrow rest and a set screw is then tightened to keep tension at brace.  What I am trying to do is attach it the opposite way at I don't like the set screw setup.  I want to attach the cord to the rest tie a knot so the cord can't be pulled back through and then attach to the upper limb like I described above.
If I understand you correctly, an HFP Slippery 8 Loop might work:
http://notableknotindex.webs.com/slippery8.html

<-----------------------<<
« Last Edit: July 11, 2012, 09:22:41 PM by roo »
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-bowfreak-

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Re: Need a knot for specific application
« Reply #6 on: July 11, 2012, 09:07:01 PM »
I am a newbie so I don't know how to embed a video but here is a video showing how it works.

http://www.youtube.com/watch?v=sbOA7NACkEY&feature=player_embedded

-bowfreak-

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Re: Need a knot for specific application
« Reply #7 on: July 11, 2012, 09:08:28 PM »
Here is how one is typically attached to the top limb


roo

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Re: Need a knot for specific application
« Reply #8 on: July 11, 2012, 09:18:31 PM »
Here is how one is typically attached to the top limb
It's too bad that you don't have a better hard point to loop into, although you could use a separate short cord to create an eyelet (loop) that gets hitched to the anchor point (with additional round turns as desired).
« Last Edit: July 11, 2012, 09:26:51 PM by roo »
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-bowfreak-

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Re: Need a knot for specific application
« Reply #9 on: July 11, 2012, 09:50:35 PM »
Here is how one is typically attached to the top limb
It's too bad that you don't have a better hard point to loop into, although you could use a separate short cord to create an eyelet (loop) that gets hitched to the anchor point (with additional round turns as desired).

That was a thought I had.  Tying a short piece of cord to the top limb using the same knot as shown in the pic.  I would then leave a loop on the other end.  I had thought I could do that and attach with a knot similar to what one use when securing a load.