Running backs -- continuous line or two part?

[memelet]

I was planning in using something t900 (partially stripped) or amsteel (partially covered) as a single line to my winches . I also want to setup the shock cord retractors described in a earlier post.

But today one of the riggers at the yard where I'm doing my work admonished me against using a single line. He said I should amsteel with thimble connected to the tail. His reasoning was that if the uncovered line gets damaged on that part would need to be replaced.

Sounds reasonable and I would no problems doing that, but I'm concerned that the thimble will interfere with the retractor block at the end of the shock cord.

First is it so important to use two parts?

And second, if I did use two parts, I'm assuming that the retrator block would need to below the amsteel on the second covered part. But in my mind (I'll probably draw this out and do the geometry) the block will want to roll over the thimble with this setup.

Can someone set me straight? Thanks!

[Brion Toss]

Hello,
What your rigger is suggesting will work, but I'm not entranced with the logic, and there are problems specific to a two-part configuration.
So where to start... well, first the possibility of damage. If you have a one-piece runner, and part of it gets damaged, you can always turn it into a two-part runner; starting with two just means two extra splices, plus that problematic thimble, and a runner that is more awkward to handle. And what is going to damage these things? HM covers are very tough, and can be replaced or mended if need be, with no damage to the structural part. You might want to leave the cover on any parts that might see chafe. Cheap insurance.
We leave the cover on all the way, usually, until it enters the single-braid tail down near the block. Then we strip the cover off, leaving an HM tail long enough to get onto the winch before the load comes on. The rest of the single braid is hollow. Single braid is fat, comfy, and easy to handle.
Fair leads,
Brion Toss

[memelet]

Thanks Brion!

Originally Posted by Brion Toss

We leave the cover on all the way, usually, until it enters the single-braid tail down near the block. Then we strip the cover off, leaving an HM tail long enough to get onto the winch before the load comes on. The rest of the single braid is hollow. Single braid is fat, comfy, and easy to handle.

I lost you here. Do mean that at this point the HM line ends and is spliced to a different single-braid? Or that you remove the cover at that point and tuck into the HM single braid?

In other words: A continues HM covered line, that remains covered thru the winch load, at which point the cover is stripped off leaving the just inside/single-braid as the tail (to eliminate bulk)?

cheers

[Brian Duff]

Other way around - HM line from mast aloft down through winch under load, with COVER ONLY tail long enough to allow retracting - the core is the HM line, the cover is just polyester.

Do single part, unless the boat actually needs purchase or spreading of load on deck dicates adding purchase, then use a straight runner from the mast through a block to the windward genoa winch. simple and effective.

[memelet]

I hate to do this, but I'm still unclear. I'll reiterate my understanding again and hope someone sees fit to set me straight.

- I have a covered HM line (say warpspeed).
- The covered line is spliced to the t-bar fitting
- The covered line runs from the mast thru the winch wraps
- After the winch the inner part (the HM part) is removed and tail (the cover) is left for retracting

Hey, I just noticed: yacht sales in Tortola! Couldn't take winter in Annapolis huh? ;-)

[Brion Toss]

Hi again,
Sorry not to have been clear. The cover is stripped just below the point where the HM enters the single braid. Then it is uncovered HM as far as needed, to be around the winch when the load comes on, then hollow single braid after that. So the single braid forms a sleeve around the HM, and takes over the job of protecting the core of the HM, plus giving you a nice fat line to handle.
Fair leads,
Brion Toss

[Brian Duff]

yup! shoving those stupid heat pads in my gloves and shoes aloft on windy Feb days was enough for me. I remembered clearly sitting on my boat in the Caribbean years ago, thinking how great it would be to have my own rig shop up on the bay. Well, that was fun but......

this is better