Cruisers Forum
 


Reply
  This discussion is proudly sponsored by:
Please support our sponsors and let them know you heard about their products on Cruisers Forums. Advertise Here
 
Thread Tools Search this Thread Rate Thread Display Modes
Old 24-04-2018, 12:46   #1
Registered User
 
captain465's Avatar

Join Date: Mar 2007
Location: Ft Lauderdale, FL
Boat: 43 ft Selene/Solo
Posts: 688
Rope clutch and Dyneema line

Has any got any real life experience using Dyneema type "synthetic" line through a rope clutch? I am intending on installing 120 VAC electric hoists for my tender, and would like to be able to control the line paying out, if I have a power failure.
The hoists have a brake on them,and the ability to "free spool". If I experienced a power failure, I could lock the rope clutch, and free spool the hoist, then use the clutch to control the paying out in order to launch the tender.
Has anyone tried this? Any comments as to the feasibility?
__________________
Do not go where the path may lead.........
go instead where there is no path........
and leave a trail.
Ralph Waldo Emerson
captain465 is offline   Reply With Quote
Old 24-04-2018, 13:12   #2
Writing Full-Time Since 2014
 
thinwater's Avatar

Join Date: Nov 2008
Location: Deale, MD
Boat: PDQ Altair, 32/34
Posts: 9,559
Re: Rope clutch and Dyneema line

Quote:
Originally Posted by captain465 View Post
Has any got any real life experience using Dyneema type "synthetic" line through a rope clutch? I am intending on installing 120 VAC electric hoists for my tender, and would like to be able to control the line paying out, if I have a power failure.
The hoists have a brake on them,and the ability to "free spool". If I experienced a power failure, I could lock the rope clutch, and free spool the hoist, then use the clutch to control the paying out in order to launch the tender.
Has anyone tried this? Any comments as to the feasibility?
I've always covered the tails, since in my experience naked Dyneema is too skinny and too slippery to hold well. Controlling a line through a clutch is not very good either. Can you get the tail on a winch drum?

And how much help is it to lower the dinghy if you can't recover it? I figure out a way of taking the tails to a winch.
__________________
Gear Testing--Engineering--Sailing
https://sail-delmarva.blogspot.com/
thinwater is offline   Reply With Quote
Old 24-04-2018, 18:15   #3
Registered User
 
captain465's Avatar

Join Date: Mar 2007
Location: Ft Lauderdale, FL
Boat: 43 ft Selene/Solo
Posts: 688
Re: Rope clutch and Dyneema line

Thinwater,
Thanks for your comments, since I have a trawler, with davits to carry the tender on the cabin top, I do not have any winch drums to take the line to.
If i had, I would not be looking to put an electric hoist on the system. (Look at my avatar pic and you will see the davits.)
I am considering the rope clutch for the possibility of launching the tender if a power failure occured, Like a fire in the generator or such. I would not be concerned with retrieving the tender very soon if that was the case.
I am aware of the slipperiness of Dyneema, but am curious as to how you cover the tails?
__________________
Do not go where the path may lead.........
go instead where there is no path........
and leave a trail.
Ralph Waldo Emerson
captain465 is offline   Reply With Quote
Old 24-04-2018, 18:59   #4
Senior Cruiser

Cruisers Forum Supporter

Join Date: Aug 2009
Posts: 4,033
Re: Rope clutch and Dyneema line

the tricky way to get bare dyneema line to work in a clutch is to put an 'internal core' in . . . this is dead easy, just take a piece of any old quite small cord and pull it into/thru the hollow center of the dyneema (using a fid). This is very neat and clean and easy and gives the clutch something to crunch on. While the dyneema is still slippery, and the clutch will probably not hold its full rated load it will still hold quite a bit - we did this on quite highly loaded reef lines. it is the pro racer technique (volvo/vendee).

Thin's suggestion of putting a cover on the dyneema also works, is a bit more work and I think a bit less clean, if well done will hold higher load in the clutch, but the cover can slip - so is also a fine technique if you prefer it.
estarzinger is offline   Reply With Quote
Old 24-04-2018, 19:42   #5
Registered User
 
Eigenvector's Avatar

Join Date: Apr 2016
Location: Mostly Texas
Boat: Lagoon 37 TPI
Posts: 541
Re: Rope clutch and Dyneema line

I think a snubber drum would work for what you're trying to do.
__________________
==========================
Now retired from the Oilfield,
Just Playing a Banjo in a Whorehouse.
Eigenvector is offline   Reply With Quote
Old 18-11-2020, 13:06   #6
Registered User

Join Date: Nov 2020
Location: Annapolis
Boat: Bristol 35.5
Posts: 1
Re: Rope clutch and Dyneema line

[QUOTE=estarzinger;2621333]the tricky way to get bare dyneema line to work in a clutch is to put an 'internal core' in . . . this is dead easy, just take a piece of any old quite small cord and pull it into/thru the hollow center of the dyneema (using a fid). This is very neat and clean and easy and gives the clutch something to crunch on.


Question: does the buried line be stitched to the dyneema line, so it stays in place? and if so on both sides or just front?
Kleim is offline   Reply With Quote
Old 18-11-2020, 14:15   #7
Registered User
 
fxykty's Avatar

Join Date: Apr 2016
Location: Indonesia
Boat: Outremer 55L
Posts: 3,794
Re: Rope clutch and Dyneema line

[QUOTE=Kleim;3277254]
Quote:
Originally Posted by estarzinger View Post
the tricky way to get bare dyneema line to work in a clutch is to put an 'internal core' in . . . this is dead easy, just take a piece of any old quite small cord and pull it into/thru the hollow center of the dyneema (using a fid). This is very neat and clean and easy and gives the clutch something to crunch on.





Question: does the buried line be stitched to the dyneema line, so it stays in place? and if so on both sides or just front?

Yes, stitch along the full length of the buried core or an external cover. In both cases, straight stitches all the way through, then a second set of straight stitches at 90*. Can be done quite easily by hand, but a machine is easier if you have long lengths.

You can see the stitching on these chafe covers for our reefing lines, made from 8mm Acera Amundsen dyneema lines.

Click image for larger version

Name:	IMG_1605736921.853057.jpg
Views:	116
Size:	440.1 KB
ID:	227200

Here are the covers on the reefing lines at the gooseneck end of the boom. The jammers are cams and really chew up the lines, so this has to be considered sacrificial and a regular wear item (a decent clutch like the Antal V-grip would be much easier on the line). Next time I will add a core as well as the cover. The red whippings are at the far ends of each cover and we’re done as burying the ends doesn’t seem to work very well on the reefing lines.

Click image for larger version

Name:	IMG_1605737262.232067.jpg
Views:	109
Size:	422.8 KB
ID:	227201

The only time you can avoid stitching an external cover is if you the original line was covered and you have removed the cover from one end. In that case the loading through the clutch will be to the covered end. The line will perform just as if you hadn’t removed the cover.

This is our running backstay purchase line. It started out as a 12mm dyneema-core with dyneema-cover line. We stripped the cover for the section that goes through the LFR purchase. Note that we had to shop around for a dyneema-core line where the core has its own UV protection - many don’t as that’s the cover’s job.

Click image for larger version

Name:	IMG_1605737530.504101.jpg
Views:	91
Size:	436.2 KB
ID:	227207
fxykty is offline   Reply With Quote
Reply

Tags
clutch, dyneema, rope

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
For Sale or Trade: Lewmar Superlock D2 rope clutch for 3/8"-7/16" rope, $70 chienbizarre Classifieds Archive 0 14-10-2012 16:28

Advertise Here


All times are GMT -7. The time now is 03:04.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2024, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.