Twisted Main sheet. - SailNet Community

   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 > On Board > Gear & Maintenance
 Not a Member? 


Like Tree8Likes
Reply
 
LinkBack Thread Tools
  #1  
Old 09-10-2012
L124C's Avatar
Senior Member
 
Join Date: Oct 2007
Posts: 1,385
Thanks: 48
Thanked 3 Times in 3 Posts
Rep Power: 7
L124C is on a distinguished road
Twisted Main sheet.

I can't figure out why my Main sheet twists above the traveler as shown in this picture. The pulleys (can't think of the nautical term, sheaves?) rotate freely in all directions, but the line twists and rubs against itself under load as shown. I can spin the upper pulley laterally and straighten the line. However, under load, it twists instantly. I would think the path of least resistance would be a straight line. Hard to believe the line could have enough memory to twist under that load! Thoughts?
Attached Thumbnails
Twisted Main sheet.-0909121501.jpg  

Last edited by L124C; 09-10-2012 at 11:44 AM.
Reply With Quote Share with Facebook
  #2  
Old 09-10-2012
rugosa's Avatar
Senior Member
 
Join Date: Aug 2011
Location: In a strange land
Posts: 505
Thanks: 0
Thanked 6 Times in 6 Posts
Rep Power: 3
rugosa is on a distinguished road
Re: Twisted Main sheet.

Try a block that doesn't swivel?
Reply With Quote Share with Facebook
  #3  
Old 09-10-2012
marcusc130's Avatar
Senior Member
 
Join Date: Oct 2011
Location: Jamestown, RI
Posts: 112
Thanks: 0
Thanked 3 Times in 3 Posts
Rep Power: 3
marcusc130 is on a distinguished road
Twisted Main sheet.

Can't see the pic, but try taking the line out of the blocks, get all the twists out of it, and re-reeve it.
sww914 likes this.
Reply With Quote Share with Facebook
  #4  
Old 09-10-2012
Senior Member
 
Join Date: Jul 2007
Location: Philadelphia
Posts: 812
Thanks: 0
Thanked 5 Times in 5 Posts
Rep Power: 8
Ulladh is on a distinguished road
Try removing the main sheet lay loose for a few hours then reinstall using the opposite end as the new bitter end
__________________
1970 Havsfidra 20 by Fisksatra
On the Delaware River at Fox Grove Marina Essington PA
Reply With Quote Share with Facebook
  #5  
Old 09-10-2012
asdf38's Avatar
Senior Member
 
Join Date: Jul 2010
Posts: 682
Thanks: 1
Thanked 4 Times in 4 Posts
Rep Power: 5
asdf38 is on a distinguished road
Twisted Main sheet.

The mainsheet is getting twisted and its working it's way through the blocks. It's easy for this to just happen but it can also be caused when you coil up the lines at the end of the sail (they should make a figure 8). You can remove the line and untwist it or figure out which way it needs to twist and force that twist back through the blocks. Braided lines are very sensitive to twisting, I find myself needing to do this periodically.
__________________
1979 Contessa 26
Boston, Ma
Reply With Quote Share with Facebook
  #6  
Old 09-10-2012
AdamLein's Avatar
Senior Member
 
Join Date: Nov 2007
Location: Coquitlam, BC
Posts: 1,866
Thanks: 1
Thanked 0 Times in 0 Posts
Rep Power: 7
AdamLein will become famous soon enough
Re: Twisted Main sheet.

My guess would be that the line is being twisted elsewhere and the twists are working their way back to the tackle. If you twist a line and fold it back into a bight, the bight will always try to take out the twists by twisting around itself.

Looking down from above, the bight has some right-handed twists, so you need to add some left-handed twists to the line itself to cancel them out. I would start at the traveler and work my way up, adding left-handed twists. You should see the block on the boom flip over.

Actually it might be easier to just unreeve the sheet, shake out the twists, and reeve it back in. Make sure that you don't add any twists in this process, of course.

Once you've removed the twists in the line, you need to figure out they got there. If you're putting your sheet on a winch, every wrap on the winch adds a twist, so make sure you shake out the line after taking it off the winch.

When you coil your sheet at the end of the day, make sure you use a figure-eight coil rather than helical coils, as the latter add a twist with each wrap of the coil. Alternately, you can do a standard coil with alternating twists, which will cancel each other out; I find the figure-eight easier to do. To do the figure-eight coil, I just pass a length of rope from my right hand to my left, where the coils are collected, without turning either hand.
asdf38 likes this.
__________________
s/v Essorant
1972 Catalina 27
Reply With Quote Share with Facebook
  #7  
Old 09-10-2012
L124C's Avatar
Senior Member
 
Join Date: Oct 2007
Posts: 1,385
Thanks: 48
Thanked 3 Times in 3 Posts
Rep Power: 7
L124C is on a distinguished road
Re: Twisted Main sheet.

Quote:
Originally Posted by marcusc130 View Post
Can't see the pic, but try taking the line out of the blocks, get all the twists out of it, and re-reeve it.
Can't see the picture at all, or it's not large enough? You know you have to click on the thumbnail to enlarge right? Anyone else not seeing it?
Thanks for all the responses. I'll take the sheet out and try relax it. I would have thought that if line was twisted, it would stay twisted when not under load. Anyway...I'll give it a shot! The main sheet hasn't been out of the blocks since I've owned the boat, except when I switched the sheet end for end. Does anyone (except for racing boats) actually coil their Main sheets after each sail? (I can anticipate the answer: "Only if they don't want them to twist!")
Reply With Quote Share with Facebook
  #8  
Old 09-10-2012
asdf38's Avatar
Senior Member
 
Join Date: Jul 2010
Posts: 682
Thanks: 1
Thanked 4 Times in 4 Posts
Rep Power: 5
asdf38 is on a distinguished road
Re: Twisted Main sheet.

The picture is good. I first read on my phone where I couldn't see it either (the sailnet app doesn't deal with pictures well. You can tap it and it eventually opens up sailnet in the browser but on my iPhone never remembers my login. So I never bother).

EDIT: Also you need to do more than relax it. Run the whole line through your hands and force the twists out in the process. You might need to do this more than once.
__________________
1979 Contessa 26
Boston, Ma

Last edited by asdf38; 09-10-2012 at 01:57 PM.
Reply With Quote Share with Facebook
  #9  
Old 09-10-2012
AdamLein's Avatar
Senior Member
 
Join Date: Nov 2007
Location: Coquitlam, BC
Posts: 1,866
Thanks: 1
Thanked 0 Times in 0 Posts
Rep Power: 7
AdamLein will become famous soon enough
Re: Twisted Main sheet.

Quote:
Originally Posted by L124C View Post
Does anyone (except for racing boats) actually coil their Main sheets after each sail? (I can anticipate the answer: "Only if they don't want them to twist!")
I absolutely do. What's the alternative? If you leave them on the gelcoat, algae will grow under them. You have to hang them up (I usually tie mine to the boom), and how do you hang them without coiling them first? I leave them out when anchoring out for the night, but when we snug down in the marina, they are always coiled.

Jib sheets are also coiled because they're permanently attached to the clews. Spinnaker sheets are coiled and hung from the pushpit. Reef lines are also coiled. My traveler control lines are too short to coil, but I still do what I can to keep them off the gelcoat. Other mast-led lines are also too short to coil.

I even coil the jib and main halyards when underway, though my sailing lessons said not to (they're led aft). Can't stand lines all over the place.
jameswilson29 likes this.
__________________
s/v Essorant
1972 Catalina 27
Reply With Quote Share with Facebook
  #10  
Old 09-10-2012
SloopJonB's Avatar
Senior Moment Member
 
Join Date: Jun 2011
Location: West Vancouver B.C.
Posts: 10,652
Thanks: 56
Thanked 48 Times in 45 Posts
Rep Power: 4
SloopJonB will become famous soon enough
Re: Twisted Main sheet.

Quote:
Originally Posted by L124C View Post
I can't figure out why my Main sheet twists above the traveler as shown in this picture. The pulleys (can't think of the nautical term, sheaves?) rotate freely in all directions, but the line twists and rubs against itself under load as shown. I can spin the upper pulley laterally and straighten the line. However, under load, it twists instantly. I would think the path of least resistance would be a straight line. Hard to believe the line could have enough memory to twist under that load! Thoughts?
Try fixed blocks. I see no need for those blocks to swivel - there is enough flex allowed by the shackles for that setup.
__________________

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
I, myself, personally intend to continue being outspoken and opinionated, intolerant of all fanatics, fools and ignoramuses, deeply suspicious of all those who have "found the answer" and on my bad days, downright rude.
Reply With Quote Share with Facebook
Reply


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

 
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


Similar Threads
Thread Thread Starter Forum Replies Last Post
Main sheet travaler nolasailor General Discussion (sailing related) 15 05-22-2011 07:30 AM
O"day 28 main sheet FourSeasMilford O'Day 2 09-11-2009 09:13 PM
How loose is your main sheet while raising the main? legarots General Discussion (sailing related) 33 06-24-2009 04:26 AM
moving the main sheet freddyray Gear & Maintenance 3 05-15-2009 09:02 AM
BV and Main Sheet Block DrB Gear & Maintenance 7 08-27-2007 11:52 AM


All times are GMT -4. The time now is 12:40 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.