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-   -   Rolling Hitch Nylon Rode Snubber ? (https://www.cruisersforum.com/forums/f118/rolling-hitch-nylon-rode-snubber-2380.html)

alaskadog 27-09-2005 06:12

Rolling Hitch Nylon Rode Snubber ?
 
This should be a simple question to some of you old salts. I want to use a rolling hitch to tie a snubber line of 5/8" nylon to a 5/8" nylon anchor rode. Prime reason is to save the main rode from chaffing where it passes through the chock before cleating. I have two anchor rodes. My primary anchor has 130 ft. of chain and 125 feet of nylon and the other anchor has 40 feet of chain on 200 feet of nylon. In shallow anchoring conditions I will use a regular nylon snubber with a chain hook because I will not have paid out the nylon rode. But in deeper water situations or if I am using my secondary anchor I will be cleating off my nylon. Since I just recently learned to tie a fairly decent rolling hitch and have yet to apply it to "real world" situations, I have two concerns. Will the rolling hitch slip and if not will it draw so tight that I have trouble releasing it? Under practice conditions it seems not to slip and to be fairly easy to untie. But I am not able to put as much pressure on it as my 14,000 lb. boat in 25 or 30 knots of wind. Thanks to all.

Vasco 27-09-2005 07:41

Joe,

The rolling hitch will always come free once you take the strain off it. We used to use it as stoppers on mooring lines on large vessels when taking the lines off the drum and onto the bitts. The hitch should be against the lay of the nylon line. To prevent chafe on my boat I put a 2 foot piece of 1" clear vinyl hose on the nylon line before the eyes were spliced. This works well .

GordMay 27-09-2005 08:50

The Rolling Hitch is like a Clove Hitch with an extra turn. When tension is applied to the snubber line , the hitch will lock onto the anchor rode. When tension is released, the hitch can be slid along the rode, adjusting the length. The hitch does not jam, and can be easily untied. These hitches are uni-directional, in that tension must be applied only to the end with the extra turn.

I use, what I believe is, a better variation - the Prusik Knot, or Triple-Sliding Hitch. I usually use three turns in each direction, but more turns = more security. This knot must be tied with a rope of diameter less than the main rope, as the effectiveness of the knot is reduced the closer the two ropes are in size. The Prusik knot is symmetrical, so is effective regardless of the direction of pull.

I understand that the Prusik has been superceded in recent years by its more advanced cousins, such as the Klemheist knot (only effective in one direction of pull).

Anyway, you’re on the right track ...
Gord

Rick 01-10-2005 12:41

Alaskadog
 
I agree with Gord and have a lot of experience using Prusik hitches with good results. Here's what you might try:

Get rid of the chain hook, you can't keep it well attached and STILL get it off easily (fast). Chain hooks also have very poor zinc coverings and you will notice that they rust fast. Use a Prusik hitch on the chain, it also works well in that application.

Use a snubber as small as 3/8" on your boat to convince yourself just how "strong" the nylon really is under conditions getting to nasty when you will probably need to go to a 1/2" snubber, and rarely to 9/16". The smaller the snubber the greater the stretch that you will "enjoy" and the less strain on your hardware.

If you are on all chain and in shallow water use a snubber that will just be attached above the bottom and it will not get too dirty. I realize that in some extreme tide changes and shallow anchoring you will have the snubber on the bottom, oh well.

Learn how to attach and unattach the Prusik with one hand. Learn how to use a long boat hook to tap the single loop of the Prusik that passes over all of the winds to loosen it and push the whole hitch further out on a rode under strain that you don't want to change the length of. You do this when you are already riding on one snubber and want to attach another which will automatically take up strain should the smaller existing one break.

I also use a Prusik to attach a lanyard attached to an aft lower shroud to the main halyard when after dropping the main. You need to be able to do it with one hand to keep the other hand for yourself. This way you never have to spend unnecessary time and physical extension removing the halyard from the headboard to keep the halyard from slapping against the mast.

alaskadog 01-10-2005 14:09

Rick and Gord: I knew there must be a better way of doing things. Guess I will just have to learn the Prusik hitch and its applications. I like the idea of getting rid of the chain hook and using a properly tied knot to do the trick. But, think I will keep the hook till I get the new knot mastered. I also like the logic of using the smaller diameter snubber instead of one the same diameter as the rode. Makes sense to me. Thanks to you both for the advice and Vasco, I appreciate your input as well.

GordMay 01-10-2005 16:11

There’s lots of additional good information, opinion, & debate at “ Heavy weather anchoring” from the Sailing Forum:
https://www.cruisersforum.com/showthr...=&threadid=533

Euro Cruiser 02-10-2005 02:57

Joe, given your W Caribbean cruising plans, I too would suggest you at least bury in a locker that chain hook. Altho' I don't like it's asymetrical loading on the chain, my big gripe with these is that they fall off the rode under certain conditions. If the wind chop picks up, at the least this will force you to march to the foredeck (from your sleeping berth; I think I can guarantee this! <g>) to reapply it.

I don't mean to be overly traditional nor a knot expert, but I've used rolling hitches now for many years, on line and chain, and I've been very satisfied with it. Since you state you already have mastered that knot, I'd encourage you to use it routinely. A good arrangement is to have several snubbers (for your intended waters, perhaps 20-25' in length) of at least one size smaller than your main rode (e.g. 1/2" if using 5/8" nylon for your primary rode).

Here's a short sea story to show how you might use it in practice. We were in the middle of a crowded anchorage by the town dock in St. Georges, Bermuda. A French boat (metal, of course...) was anchored off our port bow. A thunderstorm rolled in, the wind backed, and the French boat - now in front of us -was worried about their rode length being adequate and so started veering chain, after which they motioned to us that we were too close. (I just love self-inflicted anchoring drills...). Rather than fuss , I just went forward, released the snubber line from its cleat, and veered more chain. Snubber slipped over the side, still attached to the chain, and I applied another snubber. Very easy to work with, no rusting hardware, 1st snubber retrieved when rode shortened.

Jack

alaskadog 02-10-2005 06:03

Jack, Thanks for contributing. I sure am glad that I keep returning to threads that interest me, even those where I have no input; but especially those that I start. And using the rolling hitch on chain, tho it takes a bit longer to apply than just clipping on the hook, seems to be the smart thing to do. That was an excellent anecdote. For sure, if you had tossed a chain hook you would have likely lossed the snubber, hook & all. As it was you were able to quickly pay out more rode.

Matt Hager 05-10-2005 10:20

Is this the knot you are refering to https://www.iland.net/~jbritton/prusik.htm

Matt Hager

Rick 05-10-2005 11:03

That's the hitch!
 
Note that you can pull from either line from either direction.

GordMay 05-10-2005 12:48

Yes, that’s the ‘basic’ Prusik, or what construction riggers used to call a “Double Sliding Hitch”.
I’ve always used - and highly recommend - the “Triple Sliding Hitch”, which the site references as “adding a third turn”.

From the site:
The friction can be increased by adding a third turn.
Dress and set the knot. It is important to keep this knot neat while tightening.


See also the Prusik Knot described under Basic Roped Rescue Knots:
https://www.rescueresponse.com/html/n...technique.html
and
Transferring a Load from Belayer to Anchor via a Prusik Sling
https://www.rescuedynamics.ca/article...nterTieOff.pdf

and my favorite 'knot' site:
“Animated Knots by Grog”
Knot-Tying for Boating, Climbing, Fishing, Scouting, and Arborists
https://www.animatedknots.com/index.php

Rick 09-10-2005 18:36

Gord's correct!
 
I sometimes add a third turn, as he describes, to work on rod rigging, which is so smooth and hitches need a lot of friction to hold.

Therapy 06-04-2009 18:24

I am researching a way to use a bridle system on a cat and I just don't understand how a prussic hitch will work. I just don't get it. The knot is done with a loop of line right? It has to be passed completly through itself two or three times, right? Then you have a little bit of loop or a long double bridle line as far as I can tell.

Can someone hold my hand and walk me through this please?

Randy 06-04-2009 19:45

I just googled the Prusik hitch and came across this site: Animated Knots by Grog I think its great for clarifying a number of knots.

thinwater 06-04-2009 19:57

Close... and a tip.
 
Quote:

Originally Posted by Therapy (Post 272062)
I am researching a way to use a bridle system on a cat and I just don't understand how a prussic hitch will work. I just don't get it. The knot is done with a loop of line right? It has to be passed completly through itself two or three times, right? Then you have a little bit of loop or a long double bridle line as far as I can tell.

Can someone hold my hand and walk me through this please?

Generally you only loop through 2x, but 3x is good. One time generates a ring bend, the way you chain rubber bands together. Just go one more.

Note that the loop is smaller in diameter than the other line; this is CRITICAL. Same size will slip. The loop also must be made of soft ling or webbing.

The loops are easily purchased pre-sewn from nylon or hi-tech stuff and are much easier to work with than tied line. (Mammut Dyneema Contact Sling at REI.com)


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