What the heck is sailing rope made of?

jzmtl · **on:** August 13, 2009, 04:56:29 AM

So I was walking along the beach and found some thick rope, an inch in diameter perhaps. It was washed ashore so I assume it's sailing rope of some sort.

I wanted to see how would my pocket knife do on it so I went ahead and started slicing. Sure enough it went through rope like butter. But here's the shocker, when I looked at the blade in the evening, the edge is folded! The blade is 13c26 (440Cish?) sharpened at 40°, not the hottest but no slouch either. The rope is definitely not steel braided, could it be sand trapped in it? Still I don't think sand could do that, when I run my thumb toward the edge I can clearly feel the folded over metal, What gives?

Oh the rope felt natural, not synthetic.

ringzero · **Reply #1 on:** August 13, 2009, 07:01:14 AM

Quote from: jzmtl on August 13, 2009, 04:56:29 AM

So I was walking along the beach and found some thick rope, an inch in diameter perhaps. It was washed ashore so I assume it's sailing rope of some sort.

I wanted to see how would my pocket knife do on it so I went ahead and started slicing. Sure enough it went through rope like butter. But here's the shocker, when I looked at the blade in the evening, the edge is folded! The blade is 13c26 (440Cish?) sharpened at 40°, not the hottest but no slouch either. The rope is definitely not steel braided, could it be sand trapped in it? Still I don't think sand could do that, when I run my thumb toward the edge I can clearly feel the folded over metal, What gives?

Oh the rope felt natural, not synthetic.

Popular synthetics are nylon, polypropylene, and polyethylene.

Nylon is stronger, but polypro is more abrasion and UV resistant.

Polyethylene offers the advantage of being lower density, so it floats which can be handy for boaters.

Natural fiber rope isn't used much anymore, AFAIK. Natural fibers are sisal, hemp, and manila.

IIRC, polypro and hemp are the hardest to cut.

.

nuphoria · **Reply #2 on:** August 13, 2009, 11:51:40 AM

Is it made of sailors?

Gareth · **Reply #3 on:** August 13, 2009, 01:18:16 PM

Could it be that it's saturated with salt? It's only a guess but it seems to me that salt crystals could be pretty tough on a knife's edge.

jzmtl · **Reply #4 on:** August 13, 2009, 05:14:33 PM

Quote from: Gareth on August 13, 2009, 01:18:16 PM

Could it be that it's saturated with salt? It's only a guess but it seems to me that salt crystals could be pretty tough on a knife's edge.

It's possible. The rope was lying a couple of feet away from the sea water and tide could've saturated it over and over. Could salt really do that? It was as bad or worse than the time I cut into a staple.

ringzero · **Reply #5 on:** August 13, 2009, 10:38:01 PM

Quote from: jzmtl on August 13, 2009, 05:14:33 PM

Quote from: Gareth on August 13, 2009, 01:18:16 PM
Could it be that it's saturated with salt? It's only a guess but it seems to me that salt crystals could be pretty tough on a knife's edge.

It's possible. The rope was lying a couple of feet away from the sea water and tide could've saturated it over and over. Could salt really do that? It was as bad or worse than the time I cut into a staple.

The guy to ask here on MTO would be Dunc, who appears to have at least slight familiarity with the ropes used on boats at sea. ;>

I'm wondering if you might have a blade that got a bad heat treat. Rapid dulling could be expected, but actually rolling the edge cutting rope seems out of line to me.

However, I don't have much experience cutting rope that has been soaked in salt water and then dried out - Dunc would be the guy to ask.

.

jzmtl · **Reply #6 on:** August 14, 2009, 12:49:43 AM

Quote from: ringzero on August 13, 2009, 10:38:01 PM

However, I don't have much experience cutting rope that has been soaked in salt water and then dried out - Dunc would be the guy to ask.

.

Speaking of him, haven't seen him around lately.

Paging dunc, your presence is appreciated.

Benner · **Reply #7 on:** August 14, 2009, 12:50:25 AM

He is currently moving house.

Black Rose · **Reply #8 on:** August 14, 2009, 05:47:59 AM

Quote from: Benner on August 14, 2009, 12:50:25 AM

He is currently moving house.

Wow, he's a strong guy

Benner · **Reply #9 on:** August 14, 2009, 06:08:21 PM

Quote from: Black Rose on August 14, 2009, 05:47:59 AM

Quote from: Benner on August 14, 2009, 12:50:25 AM
He is currently moving house.
Wow, he's a strong guy

Sea Monster · **Reply #10 on:** August 16, 2009, 01:51:50 PM

What isn't sailing rope made of.

As mentioned before, natural fibres are not real popular these days.
Nylon or "Silver" ropes are the most common in a 3-strand. (which, generally, isn't actually sailing rope, for sailing you'd use a braid)

It could be part of an anchor or mooring line, or maybe someone's crab pot. In addition to sand or salt, it would likely be encrusted with barnacles and sealife.

In any case, I'd have a closer look at your blade, I've cut through various ropes with Leatherman and Vic blades, and never had any issues (I've used my OHT to hack away, axe-like, at cunjevoi & curious coral-like growths with no ill effects)

jzmtl · **Reply #11 on:** August 16, 2009, 07:38:38 PM

It looked pretty weathered so probably has been there for a long time. The edge definitely rolled, too bad there is no way for me to test the hardness and see if it's off.

Smitty44 · **Reply #12 on:** August 18, 2009, 08:39:27 PM

Could be the knife edge,and not the rope at all,if it was'nt sharped all the way,by taking of the rolled edge off,if the rolled edge is straight up and down you think that you have a razor sharp knife,until you cut something a little bit harder than paper.

jzmtl · **Reply #13 on:** August 18, 2009, 08:54:24 PM

Shouldn't be, I check my knife edge with optiloupe after sharpening. The steel is bos treated so I imagine he knows what he's doing, so I still think it's something in the rope.

Dunc · **Reply #14 on:** September 26, 2009, 04:34:41 PM

Sorry for the delay guys . Yes it could well be dried salt in the rope .But remember rope can be very hard and abrasive .I only use serrated blades on rope with Vic serrations probably being one of the best .
Do you still have some of the rope ?

Dunc