Lessons Learned From Winching

[Mark W]

Ice in the line would probably not be abrasive. The line would not be moving across it and the small size of any "edges" that could be within the line would succumb to the pressure of the line squeezing it as tension was exerted by melting or fracturing away, regardless of outside temps. ice 'crystals" small enough to be inside the strands of the line would be delicate in the extreme. Any crusted ice left inside the lines after tension was applied would create minimal stress.

Ice is rigid and very brittle when you are talking about the volume that could be contained within the rope. Easy to shatter and shed.

Any ice in or on the line will be cracked and shed, crushed and displaced long before you would reach any breaking points.

We have never seen any problem caused by cold/frozen/ice encrusted winch lines.


Fishing boats in the north pacific deal with frozen and ice caked lines all the time.


I have trouble accepting that any sort of temps found in a snowstorm (snow doesn't form in extreme cold) could have any effect on synthetic winch line.


Mark...

 

[Mark W]

Synthetic lines that we use in off road applications are often heavily based from and tested in the marine and commercial fishing industries.

And some of us simply by the line from the local distributor who supplies the fishing fleets.


Mark...

 

[TrekboxX]

I'm no physicist, but isn't darn near everything more "brittle" at lower temps? More prone to cracks/breaks/fractures, whether substantial, measurable, or not? And ice is, in fact, abrasive or at least has "cutting" ability at some level. I am not saying that ice was the proximate cause of this guy's line breaking, but to say it's not possibly a contributing factor is, well, overestimating your understanding of physics.

Sometimes it's ok to say you don't know...

 

[Mark W]

You are right... you should have just said that you don't know.
Would have been a shorter post. And more accurate.

You spend much time working with winch lines or any other gear in sub-zero temps in Concord California?

Have you dealt with ice in its varied forms a lot?

How much actual time do you have using winches under any conditions for that matter?

Notice that I am asking you... I won't just assume that you are clueless yet.

You have no idea what my knowledge or experience is, so perhaps you should be a bit slower with the snarky comments. What exactly are you basing your disagreement with my statements on?


Yep, at some point pretty much everything becomes more brittle as temps drop. But as I said before, that point for synthetic winch lines far below what you will ever see in snow storm. especially any snowstorm in the lower 48 while pulling a car out of a ditch.

I guess I should restate everything i said before, since you don't seem to have paid any attention to it?


A block of ice may have a sharp edge which can cut. That is not abrasion. And not what we were discussing

Crushed and refrozen ice can have a lot of sharp edges to it. So long as it did not get warm enough for those edges to round before they refroze.

An ice crystal may have a multitude of sharp edges that *look* abrasive.

But that block of ice will not fit inside a winch line. Neither will a crushed and refrozen block of ice.

And that ice crystal that *could* fit between the strands will not have the strength to cut or 'abrade' (would not really be abrasions unless the line was moving across it, and since the ice was suggested as being inside the line, that movement would be impossible) the winch line before the pressure exerted by the line crushes and melts it.


Under pressure, ice crystals melt. That is why we can stomp out a runway for a ski-plane in powder snow and why the snow in an avalanche locks up like concrete when it stops sliding.

If you are dragging a caribou carcass down in frozen river with a layer of hoar frost and ice crystals on top of it at 30 miles an hour behind ATV or a snow machine in sub 0 temperatures... there will be enough abrasion to wear the hair off of the contact patches at the hips and shoulders of the animal after a few miles. But not enough to damage the skin underneath.
This is about as extreme as you will see for abrasion from ice crystals.


"cuttng" ability and abrasiveness are not the same. Ice inside a winch line will do neither.

But ya know what... don't listen to me. I can't possibly know what I am talking about after all.

Are you maybe willing to accept that possibly the folks over at Samson who make the stuff might just maybe know what they are talking about? You could have done a quick google and found this before you decided to give me crap. But them you might have learned something first.

www.samsonrope.com/get.php?file=216

(page 5 of the PDF would seem pertinent here).

Some of it is kinda the same stuff Eventhough mentioned already actually. He can't possibly know what he is talking about either I guess?




Mark...

 

[Southeast Overland]

And some of us simply by the line from the local distributor who supplies the fishing fleets.

Mark...

Yup.



Y'all are blessed with many more marine stores like that on the west coast, and especially the Pacific Northwest. I pay gobs of shipping - and it would be even more if syn line wasn't so light.

 

[Mark W]

When Ratpuke was here the last time she made a group buy for a bunch of the guys in her club back home. At the time one of my guys worked for one of the marine distributors and had access to the synthetics at screaming prices. We all sat around the campfire on the trail one night splicing loops in the ends of winch lines and extensions. A couple of spools worth.

Not as easy to run downtown and buy a 600 foot spool of your favorite weight of you are in Kansas or Calgary or some place like that I guess.


Mark...

 

[cody c]

for cold weather strength of steel cable, I know that the crane operators in alberta are required to derate their lifting capacity by 1% per 1 degree below zero, i.e. 20 below C = 80% capacity.

Synthetic would be different, I couldnt say if its derated, more or less, but I'd guess breaking strength will decrease to some quantity in colder weather.

 

[Southeast Overland]

for cold weather strength of steel cable, I know that the crane operators in alberta are required to derate their lifting capacity by 1% per 1 degree below zero, i.e. 20 below C = 80% capacity.

Synthetic would be different, I couldnt say if its derated, more or less, but I'd guess breaking strength will decrease to some quantity in colder weather.

Please see my previous post, quoted below. Dyneema SK75 gets stronger, not weaker, with cold temperatures. Click on the link in my quoted post below.

Can you provide more info on exactly what happened and what type of synthetic line you were using? The most common line is Dyneema SK75 and in a lab setting it does not get weaker as it gets colder (at temperatures humans will typically see outdoors.) It actually gets a bit stronger.

Check out a document HERE and look on the first page, second column (left column) under Operating Window/Temperature.

"Temperature.
Dyneema® fiber has a melting point between 144ºC and
152ºC. The tenacity and modulus decrease at higher
temperatures but increase at sub-zero temperatures.
There is no brittle point found as low as -150ºC, so the
fiber can be used between this temperature and 70ºC.
Brief exposure to higher temperatures will not cause any
serious loss of properties."

Now there are some potential explanations as to why your line broke below freezing. Had the line been shock loaded or previously damaged?

 

[TrekboxX]

You are right... you should have just said that you don't know.
Would have been a shorter post. And more accurate.

You spend much time working with winch lines or any other gear in sub-zero temps in Concord California?

Have you dealt with ice in its varied forms a lot?

How much actual time do you have using winches under any conditions for that matter?

Notice that I am asking you... I won't just assume that you are clueless yet.

You have no idea what my knowledge or experience is, so perhaps you should be a bit slower with the snarky comments. What exactly are you basing your disagreement with my statements on?


Yep, at some point pretty much everything becomes more brittle as temps drop. But as I said before, that point for synthetic winch lines far below what you will ever see in snow storm. especially any snowstorm in the lower 48 while pulling a car out of a ditch.

I guess I should restate everything i said before, since you don't seem to have paid any attention to it?


A block of ice may have a sharp edge which can cut. That is not abrasion. And not what we were discussing

Crushed and refrozen ice can have a lot of sharp edges to it. So long as it did not get warm enough for those edges to round before they refroze.

An ice crystal may have a multitude of sharp edges that *look* abrasive.

But that block of ice will not fit inside a winch line. Neither will a crushed and refrozen block of ice.

And that ice crystal that *could* fit between the strands will not have the strength to cut or 'abrade' (would not really be abrasions unless the line was moving across it, and since the ice was suggested as being inside the line, that movement would be impossible) the winch line before the pressure exerted by the line crushes and melts it.


Under pressure, ice crystals melt. That is why we can stomp out a runway for a ski-plane in powder snow and why the snow in an avalanche locks up like concrete when it stops sliding.

If you are dragging a caribou carcass down in frozen river with a layer of hoar frost and ice crystals on top of it at 30 miles an hour behind ATV or a snow machine in sub 0 temperatures... there will be enough abrasion to wear the hair off of the contact patches at the hips and shoulders of the animal after a few miles. But not enough to damage the skin underneath.

This is about as extreme as you will see for abrasion from ice crystals.


"cuttng" ability and abrasiveness are not the same. Ice inside a winch line will do neither.

But ya know what... don't listen to me. I can't possibly know what I am talking about after all.

Are you maybe willing to accept that possibly the folks over at Samson who make the stuff might just maybe know what they are talking about? You could have done a quick google and found this before you decided to give me crap. But them you might have learned something first.

www.samsonrope.com/get.php?file=216

(page 5 of the PDF would seem pertinent here).

Some of it is kinda the same stuff Eventhough mentioned already actually. He can't possibly know what he is talking about either I guess?




Mark...

I could get into it with you, and state my background (not in CA), but I won't. I'll just say this. I guarantee YOU don't know what is happening INSIDE the winch line when the iced fibers get stretched and pulled together with great force. Nobody does. There are only theories based upon outside measurement obtained, the best we (humans) can... A good doctor will admit that "we" don't really know.

"What exactly are you basing your disagreement with my statements on?"
Honestly, just your condescending know-it-all attitude.

 

[MicahMan]

That took a turn for the worst

 

[mr jits]

Fair enough.

I've wondered about the Runva's. Many people swear by them and they look good to boot. Made (or at least assembled) in Canada, correct?

I think they're just brought in as-is from China. I haven't read a complaint yet about them. They're warranty is rock solid from my new experiences and I'd buy from them again.

 

[mr jits]

I could get into it with you, and state my background (not in CA), but I won't. I'll just say this. I guarantee YOU don't know what is happening INSIDE the winch line when the iced fibers get stretched and pulled together with great force. Nobody does. There are only theories based upon outside measurement obtained, the best we (humans) can... A good doctor will admit that "we" don't really know.

"What exactly are you basing your disagreement with my statements on?"
Honestly, just your condescending know-it-all attitude.

If ice were trapped inside the line and subjected to "great force" as you described, the ice would turn to water (simple science, ice turns to water under pressure). Water is a known factor in decreasing the strength of synthetic fibers which could lead to line failure.

 

[TrekboxX]

If ice were trapped inside the line and subjected to "great force" as you described, the ice would turn to water (simple science, ice turns to water under pressure). Water is a known factor in decreasing the strength of synthetic fibers which could lead to line failure.

I think perhaps you meant "isn't a known factor"? The one thing you forget to account for is time. Yes, in some instances ice will turn to water under pressure (not always). Park your rig on a frozen lake in the winter. Will the ice melt under the tires? Is that "great force?" Shoot a bullet of your choice into ice. Are you shooting only liquid? Ram your flesh into ice with any amount of force, if you dare. Will it turn to water before your flesh tears? Give me a break. I really don't care very much, either way, I just get irked when people say "never" or "always", or are braggers or bullies. And yes, I have extensive experience with synthetic lines in situations where the load has a heartbeat.

 

[Southeast Overland]

Water is a known factor in decreasing the strength of synthetic fibers which could lead to line failure.

Are you saying that wetness is a significant factor contributing to a reduction in the strength of Dyneema SK75? I also think you meant to say "isn't a factor."

 

[nuclearlemon]

this is like the brett young vs. jim c thread

 

[mr jits]

1407driver, you're trying to act the expert on a subject that you're obviously not (in regards to pressure and water, ie, ice), so either do some research into incompressability and what I mean by force, or quit commenting like you know what you're saying. Ice under pressure, we're talking tons per square inch here, starts to flow (liquid ice, very cold water). This is why glaciers move downhill even in subzero temperatures and also why you can cut an ice cube with a piano wire and a weight. These kinds of pressures are seen when winching, easily 4 or 5 tons of force being applied to the line itself which is enough to create the liquid ice phenomena I'm talking about. Your examples of a car, a bullet, and my hand are flawed and not even close to the amount of force a winch line is seeing under load.

On the water and winchline comment the kinetic ropes, and climbing ropes I've bought recently have come with a warning citing that I should expect a reduction in load capacity when wet. My assumption was this would also apply to the synthetic winch line and of this I look to be wrong.

 

[nuclearlemon]

On the water and winchline comment, all of the winch line, kinetic ropes, and climbing rope I've bought recently has come with a warning citing that I should expect a reduction in load capacity when wet. My assumption was that the manufacturers knew why they were making such a warning, but I may be mistaken.

what brand line are you buying? kinetic ropes and climbing lines don't matter for this conversation, just winch line.

 

[mr jits]

what brand line are you buying? kinetic ropes and climbing lines don't matter for this conversation, just winch line.

No, you're correct, I mistook the warning labels from other equipment and heaped them all together.

 

[Southeast Overland]

On the water and winchline comment the kinetic ropes, and climbing ropes I've bought recently have come with a warning citing that I should expect a reduction in load capacity when wet. My assumption was this would also apply to the synthetic winch line and of this I look to be wrong.

Dyneema SK75 (probably the most popular synthetic fiber used in off-road winch lines) absorbs very little water and is resistant to water and moisture. It is heavily used in the marine industry (commercial fishing, sailing, rigging, etc) where things stay wet.

Go to this LINK and check out the table on page three in the bottom left.

Table: Water and chemicals.
Dyneema®
Water take-up when soaked None
Boiling water shrinkage < 1%
Resistance to (salt) water Excellent
Resistance to acids Excellent
Resistance to alkali Excellent
Resistance to most chemicals Excellent

 

[TrekboxX]

1407driver, you're trying to act the expert on a subject that you're obviously not (in regards to pressure and water, ie, ice), so either do some research into incompressability and what I mean by force, or quit commenting like you know what you're saying. Ice under pressure, we're talking tons per square inch here, starts to flow (liquid ice, very cold water). This is why glaciers move downhill even in subzero temperatures and also why you can cut an ice cube with a piano wire and a weight. These kinds of pressures are seen when winching, easily 4 or 5 tons of force being applied to the line itself which is enough to create the liquid ice phenomena I'm talking about. Your examples of a car, a bullet, and my hand are flawed and not even close to the amount of force a winch line is seeing under load.

On the water and winchline comment the kinetic ropes, and climbing ropes I've bought recently have come with a warning citing that I should expect a reduction in load capacity when wet. My assumption was this would also apply to the synthetic winch line and of this I look to be wrong.

I wouldn't call myself an expert, at all, but I was trying to prove a point in terms most would understand. The concept that time is necessary to allow the "liquid ice" to "flow". All of my examples, and yours, demonstrate this. Or your glacier would flow as a river (swift). Synthetic line (and we don't know if we're talking about dyneema, technora, whatever) has the ability to store a decent relative amount of ice/water. Look at how it separates and expands when you clean (and inspect it, for live loads (people)). I can understand that dyneema may be "stronger" at 0 degrees F vs 59 degrees, but does "stronger" mean only tensile strength? Are we to believe that a winchline soaked in water and then frozen will have no reduced capability whatsoever? Show me the scientifically valid study that states that this is the case and I will believe you. Until then it's all theory and rambling. Don't forget, this started when someone was trying to be helpful to others by saying that his winchline snapped when frozen. Didn't say how, why, what kind of line, what temps, anything. But then he's berated by internet experts who are trying to disprove the validity of his statement. I don't know, I wasn't there.

And by the way, thanks for the heads up. I'll try not to winch with a frozen line if I can help it. Until I read that study...