Synthetic winch line

ntsqd

Heretic Car Camper
Clark White said:
For a warn M8000, would you suggest the high temp, or would regular synthetic line be just fine? And also, would I need to do anything to the drum since I have been using steel cable for a few years and it has probably put some abrasions on the drum? Thanks!
Highly advise careful removal of all sharp edges. If that results or looks like it will result is substantial thinning of the drum I would suggest getting a replacement.

On my own M8k, which the Border Patrol used to the point of killing the cable & the motor, the drum only required light polishing with a bench mounted belt sander fitted with 100 grit. I used the unsupported section of the belt so that it would conform to the drum shape & not dig in.
 

daverami

Explorer
With a heavy 2005+ Tacoma, would it be better to go with a 3/8" line over a 5/16"? A little extra safety perhaps?
 

crawler#976

Expedition Leader
I debated the same thing and decided to use the 5/16 to gain a few feet of extra length. I realized a M8000 is still only rated to 4 tons regardless of the size of the line, heavier line doesn't change that.
 

flyingwil

Supporting Sponsor - Sierra Expeditions
daverami said:
With a heavy 2005+ Tacoma, would it be better to go with a 3/8" line over a 5/16"? A little extra safety perhaps?

I would stick with the 3/8", it has a 13,700 lb. Breaking Strength which should be plenty... You can always use snatch blocks and line extensions if needed.

The advice given above I agree on. :beer:
 

ntsqd

Heretic Car Camper
What is the average breaking strength of the 5/16" version of the line in question?
From my research I found a 1/4" line that was only just barely stronger (on average) than the stall pull of the M8k. Seriously considered trying it until we did some pull to failure tests on a sample of a slightly less strong version. Would work, but was cutting things a little too close.
 

madizell

Explorer
Don't use 1/4 inch line on anything larger than an ATV, and don't go by the tensile rating of the line, that is if you are using an 8,000 pound winch, don't buy rope with a burst strength of only 8,000. You will break the rope if you do.

In order to use rope, you will have to splice in an eye, or the manufacturer will, which degrades burst strength. If not correctly done, it can cut the strength in half. Assume that you will only have access to 90% of rated strength when brand new and clean with a correctly done splice, and as a rule of thumb, assume you only have access to half of the rated strength of rope in day to day usage. Buy accordingly. I have an 8274-50 rated conservatively at 8,000 pounds, but I have had far more load than that on the winch and rope. I use line rated at around 18,000 pounds, and I consider that a minimum strength for a 5,300 pound vehicle and an 8,000 pound winch. If I remember correctly the line is 8mm or 9mm, which should be equivalent to 3/8 more or less. 5/16ths is okay for light duty foofoo work. Length of rope on the drum is largely not relevant. You will always have too much or too little no matter where you get stuck, so carry extensions and straps. Besides, as mentioned winches work best when fully unloaded, so short drum capacity is not a drawback if you have extensions on board.
 

ntsqd

Heretic Car Camper
In the brand I was looking at the 1/4" lower rated stuff was only-just-barely rated stronger than the winch itself. There is a stronger grade that would have been the purchase had that trigger been pulled. The margin of the lower strength stuff was close enough to make me wonder if it really was strong enough given that it was listed as "Average Breaking Strength", which is why we ran some tests (i.e. what exactly does that mean in real world use?).

The line I tested to failure was impressive. We used an 8274 to pull on it, and anchored the other end to a 1ton mid 70's Chevy CC SRW w/ loaded down service bed, in park with the p-brake stomped on and the RR tire chocked sitting on asphalt. Every failure except those which were knot tests moved (dragged) the truck back. Pretty darned impressive for a 1/4" rope.

In the knot tests we were looking for a method to do quick in the field mid-line repairs. Conclusion was no knot known to us (with ref books prior consulted & best options chosen) will work. All knots failed in the first sharp bend. The rope was best described as looking melted at the parting. A splice is the only option in that particular rope.

Given my results I personally won't hesitate to buy the stronger 1/4" rope should I decide to actually mount that winch on Patch, the wonder yota. I will NOT advise or suggest that anyone else to do the same. Were the winch intended for the Sub then the 1/4" is not an option.
 

crawler#976

Expedition Leader
ntsqd said:
What is the average breaking strength of the 5/16" version of the line in question?
From my research I found a 1/4" line that was only just barely stronger (on average) than the stall pull of the M8k. Seriously considered trying it until we did some pull to failure tests on a sample of a slightly less strong version. Would work, but was cutting things a little too close.

Per Winchline.com the 1/4 is rated to 5400, the 5/16" @ 13,500, the 3/8" @ 19,600.
 

madizell

Explorer
My opinions regarding synthetic line, and they are merely opinions and not scientific results, are based on real world use of plasma and kevlar ropes on tough trails and in desert racing where winching is emphasized. I have fortunately never broken a rope in actual use in the field, but have broken one in my back yard winching stumps. Personally I would not use synthetic line of a strength less than comparable steel cable intended for the winch in question, and even that is under-rated as far as I am concerned.

Bursting strength of synthetic line is tested on special equipment using unspliced line in perfect condition, not subjected to a bending moment, and not previously stretched or placed under any kind of a load. If, under such circumstances, a line is rated at 13K pounds, you will likely never see it do any better out in the field, attached to a winch, impregnated with dust and sand particles, and bent around a hawse or roller fairlead in 110 degree weather.

The conditions which degrade line performance are largely not under our control. We can do our best to keep the rope clean and out of the sun, and away from sources of heat and abrasion, but the environment in which I find myself when off road simply isn't well blessed in these attributes.

Unlike fishing for trout with ultralite gear, recovering a vehicle when off road is not exactly a sporting proposition. You may be able to place light line under significant strain on your driveway and get away with it, but toss the rope into a gritty mud puddle, let it bake in the sun until dry, drag it around the driveway for a few minutes, then repeat the test. This is pretty much the environment our winch lines live in, which is why I suggest a significant margin for error.
 

p1michaud

Expedition Leader
Winch lines.

flyingwil said:
I would stick with the 3/8", it has a 13,700 lb. Breaking Strength which should be plenty... You can always use snatch blocks and line extensions if needed.

Excellent advice concerning snatch blocks and extension lines.

daverami said:
With a heavy 2005+ Tacoma, would it be better to go with a 3/8" line over a 5/16"? A little extra safety perhaps?

For the price difference, get the 3/8" in 80' and you won't regret it. As wil mentionned above, you should purchase a quality snatch block and extension line or strap to go along with your recovery kit.

Out of curriosity, have you had your Tacoma on the scales fully loaded? If you are concerned about the line weight, I'd also make sure to look at vehicle weight and winch capacity. For example. My tacoma fully loaded is hovering around 5250 lbs. So in a real good stuck (up to your frame rails in mud for example) you could be faced with pulling in excess of 3 times the weight of the vehicle. That puts me at 15 750 lbs or very close to the 16 000 lb capacity of the M8000 winch using a snatch block, under ideal rigging conditions and no losses due to friction or from the electrical system supporting the winch operation. Just a bit of food for thought.

Cheers :beer:,
P
 

michaelgroves

Explorer
Consider buying a stronger extension line than your main winchline too. Then you have the option of using it on the "far" side of the snatch-block, where the pull is doubled.

Also keep in mind that at stall, an electric winch can generate far greater momentary loads than its rated capacity. Unfortunately, the excess is too random to predict (an electric motor theoretically has infinite torque at the moment of stall). But on some industrial electric winches, the stall pull is as estimated as 2 - 3 times higher than the rated pull!

One more point: breaking a synthetic winch rope is expensive and inconvenient. But if you're using the winch properly, it's not hugely dangerous. On the other hand, if other parts of your rigging give way (shackles, anchors, harnesses, towing eyes, winch mounts, etc.), that's when things can turn nasty. So keep that in mind when you are deciding what equipment to buy, and regardless of the capacity of the winch, make sure the rest of the rigging is stronger than the rope.
 

asteffes

Explorer
Those of you concerned with heating up the line may want to look at the Superwinch EP9.0, which has the brake mechanism outboard of the line drum. This prevents the brake from transferring heat into the drum and thus the line.

I mounted one of these in my '06 Taco's ARB bumper, with the solenoid pack mounted underhood (required for this truck and bumper.) It is heavier than most winches, but you get 9000 pound capacity and total safety for your synthetic line.
 

bigreen505

Expedition Leader
My knowledge and experience with winching could fill and thimble and leave room for cream, but I do have some practical knowledge with synthetic ropes. So, with that in mind ...

michaelgroves said:
It's just a guess, but I would think that a rope bent at 60 degrees around a fairlead will lose between 25 and 50% of its strength.

I'm not sure I would agree with that. You are not really compromising line strength until you force it into an arc that is tighter than its natural radius (the tightest bend you can make a line take without any tension applied). This is why knots are bad. That said, I suppose I could see that bending it around a hawse fairlead could reduce rope strength (mostly because of sliding force), but no way on rollers.

daverami said:
With a heavy 2005+ Tacoma, would it be better to go with a 3/8" line over a 5/16"? A little extra safety perhaps?

You can never exceed the pull strength of your winch, with the unlikely exception of shock loading. What that means is if you have an 8,000 lb. winch, you will never exceed 8,000 lb. of force on the line. If you rig a bunch of blocks your pulling power could greatly exceed your rated winch capacity, but the actual load on the line will not. While synthetic lines are designed to work at high percentages of their max working load, moving out of the theoretical environment of a Web forum and into reality, you introduce the two most detrimental ingredients to a rope: grit and UV.

Synthetic lines, particularly any sort of Dyneema (Amsteel Blue, et al) achieve their high working loads by self-lubricating the individual fibers allowing them to slide over each other without friction as the rope constricts under load. Add some grit and the fibers cut instead of sliding. You also will lose a bit of strength (figure 10 percent for safety) fore each splice.

So you should work in a little cushion, but you don't need to go crazy. 5/16" Amsteel Blue (Dyneema SK-75) has a tensile strength of 13,700 lb., 3/8" has a tensile strength of 19,600 lb.

So where does theory meet reality? In theory 1/4 Amsteel blue (tensile strength 8,600 lb.) should be sufficient for an 8,000 lb. winch. Experience here on the forum suggest it isn't. I would enter that having a line with a breaking strength double your winch is overkill, but 1.5x seems reasonable. Just keep it off sharp rocks.
 

madizell

Explorer
bigreen505 said:
Just keep it off sharp rocks.

...and out of the sun, and out of the wind, and away from heat, and off the front of your vehicle until needed, and clean it carefully after every run, and replace it every season...

Since these are impractical notions, line degradation is far faster than one might expect, at which point x2 line strength over winch capacity is not overkill, but a working world safety margin that allows you to get some useful live out of the line before you need to replace it, and allows enough margin that you won't need to worry constantly every time you need to use the winch. Under-rate the line and you will be replacing it every other season.

For that matter, if you really don't want to use line stronger than 13,500, why change to synthetic if you are already equipped with steel? You have to wear gloves anyway. Steel cable can last longer than your car will. It is resistant to abrasion, and if treated with as much care as you need to give to synthetic, will outlast the winch. And, if you already have steel cable, keeping it costs nothing. Synthetic runs $2 to $3 a foot.
 

hochung

Adventurer
michaelgroves said:
Of course if you get a proper hydraulic or mechanical winch, instead of one of the electric toys, then it's not an issue at all... :wings:

can you please elaborate on this? what makes the mechanical or hydraulic winches different?
 

Forum statistics

Threads
190,104
Messages
2,923,982
Members
233,414
Latest member
dhuss
Top