Jump to content

Mainsheet barney/swivel with gross tune + fine tune + backstay


Recommended Posts

I'm planning to convert my main sheet setup so it's mounted on a centered swivel aft of the traveller, rather than moving with the traveller. This seems pretty straightforward, but I also have two other goals:

  1. Preserve the fine tune
  2. Consolidate my split backstay control lines into a single control line

The obvious solution is to get a Harken "duocam" swivel base (HK-216), which supports replacing the top cleat with a double cleat (HK-412) giving me 3 cleats total. I figure with this setup I can have my main sheet fine and gross tune cleated to the top arm, and the backstay cleated to the bottom arm. Not a huge fan of the metal fairlead on the double cleat, but I figure I could also make an adapter plate and use two side-by-side single cleats with nicer fairleads.

What gives me pause is that I've seen other boats like the J105 and J88 where the gross tune and fine tune go to two different swivels on either side of the traveller. Not sure if they do this to avoid friction in the system, trimming ergonomics, load bearing or something else.

I've sketched my current setup and what I'm leaning towards as version 2. Any comments or pointers?

Mainsheet rigging 1.0.png

Mainsheet rigging 2.0.png

Link to post
Share on other sites

looks like version 1 is a 4:1  coarse tune, don't think the 5:1 setup for V.2 will work since the fine tune will need to be eased to let the boom out otherwise the blocks will bottom out against the block on the boom and then everything will stop right there. staying with 4:1 coarse tune on v2 would work however since the fine tune "stays" at the traveler blocks

 

A split backstay control near the ends of the traveler is pretty common boats like J24s and Melges 24s as well as things like J29s. I am guessing the split setup will not work for your boat? 

Link to post
Share on other sites

Hmm, I think you're right that V1 is 4:1 / 16:1.

And now I see the flaw in V2...as the gross tune is eased, the fine tune is also being effected and the two inner fine tune blocks would quickly collide. I can't think of a way to make this work with a single swivel.

Link to post
Share on other sites
2 hours ago, Rushman said:

In version 2 is the fine tune actually 4:1?  Looks like 3:1 to me but perhaps I need another coffee

I count 4; through the block on the swivel up to boom (1), down to bottom block (2), up to top block (3), down to dead-end (4). But as ctutmark pointed out, it doesn't work because the fine tune moves with the gross tune rather than being anchored outside of it.

Taking another look at it I think I might have a version that would work...

Mainsheet rigging 2.1.png

Link to post
Share on other sites
50 minutes ago, atnan said:

I count 4; through the block on the swivel up to boom (1), down to bottom block (2), up to top block (3), down to dead-end (4). But as ctutmark pointed out, it doesn't work because the fine tune moves with the gross tune rather than being anchored outside of it.

Taking another look at it I think I might have a version that would work...

Mainsheet rigging 2.1.png

The tail of the fine tune between the cleat and the boom block doesn’t count towards purchase, it is just a redirection on the tail. Happy to be educated but that is how I was taught back when Adam was a boy

Ver 2.1… If you play the traveller a lot be careful the leech doesn’t over tighten, unless you have a curved traveller

Link to post
Share on other sites
15 hours ago, atnan said:

I count 4; through the block on the swivel up to boom (1), down to bottom block (2), up to top block (3), down to dead-end (4). But as ctutmark pointed out, it doesn't work because the fine tune moves with the gross tune rather than being anchored outside of it.

Taking another look at it I think I might have a version that would work...

Mainsheet rigging 2.1.png

That looks pretty similar to the setup on my new toy, with the exception of the back stay. 

68634968-38D1-403E-97EF-F837AC8F8E96.png

Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...