Splice strength

[Marin]

Given two nylon lines of equal diameter, say 1/2", one braided and one three-strand twisted, if each one has a stainless thimble spliced into one end, does anyone know which type of line will have the stronger splice?

Or will both splices be sufficiently strong that the lines themselves will fail before the splices do?

 

[FF]

The lines will fail AT the splice , either way , as thats the weak point.

I prefer to use an anchor hitch , or a bowlin with two turns around the anchor shackel.

The reason is its not much weaker than a great splice , and it can simply be cut off to change anchor rodes.

I carry 3 bow anchors , 60 CQR , 60 Danforth and 60 Bruce.

I also use either of two nylon rodes 5/8 for most O'nite and 7/8 for heavier weather.

There is also a choice of 200ft of 3/8 Hi Test , for coral and non storm use.

To be able to switch to the "best" choice for the anchorage takes flexibality , over "ultimate"strength.

An unattended mooring would get a splice ,

FF

 

[Keith]

FF, you're really weakening that line's breakig strength by putting a knot in it. Here's an excerpt from one site: http://www.boatus.com/boattech/casey/SpliceRope.htm
"Anchor lines also require an eye splice, in this case around a metal thimble so the line can be shackled to the chain lead on the anchor. The thimble protects the line from chafe. When the "business end" of an anchor line begins to show the effects of rubbing on the bow chocks and across the bottom, you can extend its life by reversing it end-for-end--yet another reason for knowing how to make an eye splice. A knot is a poor substitute for a proper splice. A bowline, for example, reduces the breaking strength of a line by about 40% while a splice retains 95% of the rope's strength."

Here's another site with a lot of testing of knot strength, but not splices:
http://www.caves.org/section/vertical/nh/50/knotrope.html
I've never seen a test on a thimble splice: three strand vs. braided. However, I know I can splice the three strand very well. Despite my best efforts and various gadgets includin Brian Toss' splicing wand, I've never been able to make an eye splice in braided rope. Either splice will fail before the rope does, but good ones should retain maybe 95% of the line's original strength if done well, according to Casey above.

Here's a good photo description of making an eye splice in braided rope. It's a little different than the classic instructions, might have to give this one a try. http://www.thecoastalpassage.com/eye_splice.html

 

[Dark Side]

That last site, the one showing the braid over braid splice, is an instruction that is ususally reserved for dacron lines -- which are not recommended for mooring lines.* There*IS an eight strand braid in nylon that is highly thought of by some and there is a method of splicing that type of line -- but I never learned to do it.* The three strand nylon splices very easily and there is an excellent rope to chain splice that I've used for years with good success.* Have you looked into this approach?

DS