Learning to Splice

[dbeck]

TO not nick the needles...I use some black tape layers taped to the face of pliers...give bueno grip and no nicks

 

[rborist1]

:Eye:

 

[NickfromWI]

What did you make the split tail out of?

 

[rborist1]

:Eye:

 

[Lumberjack]

Hey nick or other knowledgeable persons:

I came across a .pdf doc. on samsons page.

It stated the abs of a spliced arbormaster rope (blue black yellow streak) was 6,480. Where did all the strength go? Thats a 20% decrease in strength of the rope? I never thought that it would be that much. Is this just the way it is on a splice on 16 strand or what?

 

[dbeck]

From what I understand, a spliced rope can retain up to 90% of the original strength. When you tie a knot in that line you can cut the strength by as much as 50%. This is where spliced eyes in climb lines(for ex) are appealing to some...others would rather use the proven knots. Use whichever you want, just make sure you do it correctly!

 

[NickfromWI]

Originally posted by dbeck
Use whichever you want, just make sure you do it correctly!

Good point!

When regarding my climbing line, I prefer splices for their cleanliness. Less bulk and clutter on my saddle.

It is quite doable to obtain 100% rope strength with a splice. That is why they are so good.

In some ropes, a comprimise has to be made between strength and usability. A stronger splice in the 16strand ropes might be bulkier or longer. It really is unneeded. Many friction hitches won't grab on that tight part of rope at the throat/bury of the splice. If it is the case that a longer taper will give you a stronger splice in this rope, you might end up with a 100% splice, but 18" of rope that you in a sense cannot use. Your hitch won't grab it.

I like the 16 strand splice.

love
nick

 

[John Paul Sanborn]

Originally posted by NickfromWI

It is quite doable to obtain 100% rope strength with a splice. That is why they are so good.

Is that not because the rope specifications are made with the splice, not because the splice does not diminish the tensil of the rope?

 

[NickfromWI]

John, from what I've seen, it varies. Some manufacturers report the spliced rope. Some report it after pulling around a pin of a certain size.

Sometimes the companies will put an asterisk by the strength and if you look down they'll tell you how it was obtained. I like when they do that!

love
nick

 

[Kneejerk Bombas]

The best splices come from the manufactuer. Aftermarket splices are ok, but are second best.

 

[NickfromWI]

Best in what sense, Mike?

The only splice failure I've (due to splicers negligence) that I've heard of was a factory splice.

love
nick

 

[Kneejerk Bombas]

If you can tell me why a splice reduces the strength of a rope at all, Nick, I'll tell you why the manufacturer can make better splices.

(Hint:strand tension)

 

[NickfromWI]

Originally posted by Mike Maas
If you can tell me why a splice reduces the strength of a rope at all, Nick, I'll tell you why the manufacturer can make better splices.

(Hint:strand tension)

Mike, in your mind, how is strength loss from splicing related to the quality of factory splices versus aftermarket?

A rope is at it's strongest in a straight line. Unfortanately, you cannot connect it to anything like that...rendering it useless. An many (but not all) splices, the rope is doubles over then stuck inside itself.....it's buried. As tension is placed on the eye of the splice, the outside cover strands tighten down and grab ahold of the buried strands. This holds them in place. This is your splice (in some ropes...like the 16 strand).

Now, if you were to bury say, 7 inches, then cut it off right there, you'd feel a noticable lump or dropoff inside the rope. This is where your useful hint comes into play. As you begin to pull on the rope, tension is put on the strands. In your splice, that sharp dropoff can act much like a knot in the sense that there is more tension placed at the outside of the curve of the knot. Here, more tension is put on the parts of the strands right at the tip of the bump. It sortof causes a shearing affect at that point. A big portion of the load is put at the strands at the high surface of the "bump" in the rope.

This is why a smooth taper is crucial to proper splicing. In a smooth taper there is no bump. There is no one spot that is taking a lot of the load. The load can be evenly spread throughout all of the strands. In most ropes, a smooth taper will result in higher breaking strengths.

So the issue of "better splices" in this sense is not in who is doing them, but rather how they are doing it.

So Mike, why do the manufacturers make better splices. I take pride in what I do. I also have no time constraint. Where someone who is pushed for time might be tempted to just cut off the last inch or two in a quick taper, I will take all the time in the world to spread that taper out as much as is reasonable.

I am not arguing that factory splices are better or worse than aftermarket. I don't think you can make a broad statement that will apply to all situations. What it comes down to is the individual person making the splice.

love
nick

 

[Kneejerk Bombas]

As the rope is made, and is nearing the end of a length, the machine that makes the rope is controlled by a computer and starts to loosen the tension on the strands for a distance of future bury. It starts out slightly lose and progesses to just loose enough to accept the bury.
Now, when the bury is made strand tension is very close to the strand tension in the rest of the rope. When strand tension is the same throughout the diameter of the rope, it is stronger. The strength loss in the taper is no longer there, in fact, it's strength is greater!
You may be able to milk Nick, but you ain't no computer.
If you want any more help on splicing theory, just let me know. Hahahaha...

 

[NickfromWI]

Good point, mike. Unfortunately, this is a technique used by very few manufacturers and for very few types of rope.

Most of the spliced ropes you see being sold at Sherrill, Fresco, Sierra Moreno, Aerial Equipment, etc were made by machines that had ONE setting.

In what ropes that you know of do they do that, Mike? Why is it done? In the ropes I know of, the adjustment of rope tension is not done to make a stronger splice...it's done to allow a splice in a rope that is considered unspliceable. It makes it easier for the factory riggers to crank these splices out.

Super strong splices (just about 0% strength loss) are created in ropes where no adjustment to strand tension was made. Are all these manufacturers and splicers in the wrong? I don't think so

I maintain that factory splices are not better. Better splices are better.

love
nick

 

[Kneejerk Bombas]

Fair enough Nick, just so we both agree factory splices are better.

 

[NickfromWI]

Oh, Mikey. You make me laugh.

I have to go do laundry now.

love
nick

 

[TheTreeSpyder]

The technique MM refers to i think is for 'unspliceable' tight arbo 12 strand (other 12 strands can be spliced without brummel, but their directions don't aplly to us as i understand).

Splicing can make you a better knotter IMLHO, in that the techniques of polishing 100% efficiency from line, is just superlative line handling, hints of which could applicate to any knot/hitch(?)

Starting on the simplest, that as knot tyers any tree person should know i think; simple, strong lessons can be learned....

Brion Toss's (also where the 'sweating in' comes from) excellent VHS tape, at a good Sherrill price of $32 (co$t of 2 16 strand splices) if your into this stuff, #16232. One gleaming point of the ol'master to 3 strand, showing a consideration of all knotting i beleive is his 'ribboning' theory.

In the 3 strand, the big ribboning secret (contrary to popular belief according to the recognized worldwide authority on knotting, splicing, rigging and boating lore) is to take the round strands and ribbon out/ flatten before weaving thru to make splice, not to leave round. This one simple action, maybe an unnoticeable differance almost in watching 2 people do the same thing, mechancically does 2 things: by being flatter as it weaved through line a lacing ribbon disturbs the line shape less; thereby maintaining strength. Also a flat ribbon of strands lacing thru, gives more surface contact area ; like closing book on finger or file card; so is more secure. 2 optimized, important properties from 1 simple lil'rope prep crafted!

Anytime you can maintain natural line shape; including running flat/straight as house spliceing tech /authority Nick lends; you maintain peak strength. Any bending or curving causing leveraging against the line's strength. Any knot/hitch/splice (permanenet super knot) that has more mated, loaded surface contact has more security. Strength and security are 2 different categories of consideration in any lacing, rigging, knotting, splicing etc. Also splices and the crown knot for 3 strand, allow the load to be carried evenly on the strands of the rope.

3 strand makes good short stuff, more durable than braid in olde split tails and lanyards. Also, different and to me positive charachteristics mixed with braids in friction hitching. the contact footprint is different, and may allow heat dissipation with it's 'flutes' compared ot a totaly covering sock of a braid i think. i run a 3 strand lanyard mostly, with the Rocky-Recomended NE Sta-Set white-8mm 4400# Double Braid as adjuster tied straight to D, stanidng end of lanyard thru to have D also as tender. Better for 3 strand prussiks and tails on braids though IMLHO. i beleive some Sherrill and ArborMaster refrences to same. So plenty of uses for 3 strand, no need to waist projects. i think easier with marked line favoring NE HYvee 3 strand. The other 3 strands ya might see i'd steer away from the stiffer polyolefin(SP.?) stiffer fibers, that are kinda easier to splice, but don't lay down as well for the ribboning IMLHO. Also those fibers don't take heat as well, and are weaker 'hamburger helper' IMLHO.

 

[murphy4trees]

anyone see the splicing article in TCI mag pg 50, 3/04... a few good points, but also missed some pretty basic stuff and due to its tone might as well be called "not splicing" instead of rope splicing.