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Discussion Starter · #1 ·
More toys is reason enough for a new thread :p

So far the smittybilt is working out nicely. I ended up purchasing the XRC8000 and added the 100' 5/16 syn rope (they had a package deal for a little cheaper, but were waay backordered). After a few simple winch tests over the holiday weekend, I can't emphasize enough how awesome rope is compared to wire :eek:

The smittybilt is pretty good for the money, especially the killer deal 4wheelparts was having during my shopping extravaganza. I believe the motor is 5.5hp which is pretty quick. Once my tcase is back on track, I'll get some video or better uphill tests.

A couple quick lesson's I've learned so far...
  1. Winch strength is strongest as you spool out the line, note you have to leave ~5ft of line always spooled. So a 100ft line quickly becomes 95 or 90 usable
  2. You need slack when setting up your rigging and shackles, this requires a few more feet easily (you're roughly at ~90-85ft usable out of 100)
  3. Having a snatch block setup to double your pull is ideal! Of course, this reduces your useable line to a anchor in half, but greatly increases your pull strength

I'd definetly go with 125ft if I had the chance again. This with the assumtion I'm going to use my snatch block as much as possible
 

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2002 chevy trailblazer_lt
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Discussion Starter · #2 ·
Pics...

New winch line wrapped but not under tension:


Winch line under tension. Notice how much more room there is for 125' :cry:


Notice the double shackles on the rigging. This allows the snatch block to maintain a level position with the line. One shackle produces a drastic angle which your line can slip and jam the block, yuck:






 

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A couple quick lesson's I've learned so far...

- Winch strength is strongest as you spool out the line, note you have to leave ~5ft of line always spooled. So a 100ft line quickly becomes 95 or 90 usable
It's my understanding that the pull rating is based entirely upon how many layers of line are below the pulling line. For instance, if the line is laying on the drum, you have your max capacity. However for each layer below the pulling line, you effectively increase your spool diameter, and thus with the same torque from the winch, you have less leverage due to the increased drum diameter.

This is why a shorter line is nice sometimes, because you don't have to spool your line out 80 ft in order to get your max pull force.
-You need slack when setting up your rigging and shackles, this requires a few more feet easily (you're roughly at ~90-85ft usable out of 100)
This is something I hadn't thought about before, and a good point. Your usable line really is about 10' less than the actual rope length.
-Having a snatch block setup to double your pull is ideal! Of course, this reduces your usable line to a anchor in half, but greatly increases your pull strength

I'd definitely go with 125ft if I had the chance again. This with the assumption I'm going to use my snatch block as much as possible
I really like the idea of a snatch block too. The thing I've read, however, is that people overlook their other equipment, such as the tree strap in this configuration. If you load your winch down to 8000 lbs in a double line pull, your tree strap, D shackle, and pulley needs to be rated to at least 16,000 lbs. Thats 8 tons. I don't know about you, but my biggest shackles (7/8") have a WLL of only 4 3/4 tons (9500 lbs).

So just make sure your hardware is up to spec. You want your 'fuse' to be the winch motor stalling, not a component of the system failing.

(Edit, also remember that this doubles the force on the bumper. Make sure all your attachment bolts are grade 8.)
 

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If anyone is looking for the 'quintessential' winching guide, check out the Spring 2009 edition of the Overland Journal.



It has a 10 page article written by Bruce Elfstrom (with Overland Experts) packed with some great winching information. It helped me. Here's a small excerpt:

OVERLAND JOURNAL said:
Winching Mantra:
The basic operational aspects of a winch

  • Slow down, chill out, then make a plan.
  • Always wear gloves, sturdy boots.
  • Define why you are stuck before you grab gear - never make assumptions.
  • Stabilize the vehicle before you do anything
  • Gather all needed gear in advance (best if its all in one bag).
  • Slow down and methodically implement your plan.
  • Remove all non-essential people from the hazard area.
  • Envision the places where you could get hurt if the rigging fails, and do not go anywhere near them.
  • Never put a rope between your legs.
  • Never let a rope slide through your hands.
  • Always make every effort to arrange a straight-line pull.
  • Pull out most of your rope, but leave 10 wraps.
  • Keep contact tension on the rope, especially metal rope.
  • Stay at least twice the stopping distance of the winch motor away from the fairlead.
  • Set a parachute rig between each anchor point, turn or fulcrum.
  • Use hand signals; no shouting.
  • Arrange a closed-rope system. Avoid open hooks when possible.
  • Never tow with a winch.
  • Never lower a load with a winch.
 

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Discussion Starter · #5 ·
It's my understanding that the pull rating is based entirely upon how many layers of line are below the pulling line. For instance, if the line is laying on the drum, you have your max capacity. However for each layer below the pulling line, you effectively increase your spool diameter, and thus with the same torque from the winch, you have less leverage due to the increased drum diameter.

This is why a shorter line is nice sometimes, because you don't have to spool your line out 80 ft in order to get your max pull force.
Exactly... With a longer line you would most definitely wanna leverage a block setup.

JamesDowning said:
I really like the idea of a snatch block too. The thing I've read, however, is that people overlook their other equipment, such as the tree strap in this configuration. If you load your winch down to 8000 lbs in a double line pull, your tree strap, D shackle, and pulley needs to be rated to at least 16,000 lbs. Thats 8 tons. I don't know about you, but my biggest shackles (7/8") have a WLL of only 4 3/4 tons (9500 lbs).
This area gets a cloudy from so many posts on the 'net. In the configuration I had, the setup was actually a 'traveling block' setup as the winch was hooked through the block and anchored back to my truck. Essentially 4000lbs from the winch to the block and another 4000lbs from the block back to my bumper.

However, should the anchor be moved from my truck to another secure location, the block would then need to be rated for double the load. 8000lbs from my truck/winch. 8000lbs from the other anchor.

It gets even more fun with numerous blocks :crazy: Or blocking yourself in reverse with a winch on the front of your truck :eek:
 

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This area gets a cloudy from so many posts on the 'net. In the configuration I had, the setup was actually a 'traveling block' setup as the winch was hooked through the block and anchored back to my truck. Essentially 4000lbs from the winch to the block and another 4000lbs from the block back to my bumper.

However, should the anchor be moved from my truck to another secure location, the block would then need to be rated for double the load. 8000lbs from my truck/winch. 8000lbs from the other anchor.
If a double line is still only able to produce 8000 lbs of recovery force, whats the advantage of a double line pull? 1/2 the speed?

The winch can put 8000 lbs of force on the winch line. If that same winch line is connected back to the vehicle (and not attached to the drum itself) then if the winch is maxed out, there are two lines each with 8000 lbs of tension attached to the vehicle, producing 16000 lbs total force. That same force must be equaled at the anchor point.

For example, if you were doing a pure traveling block setup such as below:

You could lift a 100 lb block with only 50 lbs of tension in the line (assuming parallel lines). Right, thats real basic and I'm sure we agree there.

There is actually no difference in rope tension between mounting the rope to your vehicle, or to another tree beside you... the recovery difference however comes from how much total tension is acting on the vehicle.

Maybe we are saying the same thing here in different ways. Are you assuming you only require 8000 lbs to recover the vehicle? In that case, yes, the winch load would be half, and you would only have 4000 lbs of tension on the line.

My scenareo involved maxing out the winch at 8000 lbs. If you ever did max out the winch in a double line pull, you would require at least a 16000 lb WLL on all of your pulley hardware (except your tree strap, which could theoretically be almost half that, because the stress is being shared among the two lines).

Oy... too many words again. :duh:
 

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Discussion Starter · #7 · (Edited)
If a double line is still only able to produce 8000 lbs of recovery force, whats the advantage of a double line pull? 1/2 the speed?
Half the force necessary on the winch but for twice the duration/distance of the pull. The truck and anchor are moving as one. Winch pulls in 1ft of line, but only moves the truck .5ft (since the line is halved). Of course, more line unwrapped allows more power available for the winch, too!

Your diagram is correct, except the force being pulled is from the 'load', not some other source. That makes all the difference, which I think we're on the same page.

My scenareo involved maxing out the winch at 8000 lbs. If you ever did max out the winch in a double line pull, you would require at least a 16000 lb WLL on all of your pulley hardware (except your tree strap, which could theoretically be almost half that, because the stress is being shared among the two lines).
That would follow the same line of thinking. But I can't imagine that much load on one of our trucks??? It's not practical, imo.
 

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There has to be more to this than D-rings and their 9500 lb rating, or why would Warn, ARB, etc. kits come with those types of D-rings but also include a snatch block that is rated at 29,000 lbs?

http://www.ok4wd.com/index.php/catalog/product/arb_3_4_clevis/

And in their winching tips show a diagram like James put up which is:
- tree strap
- 1 D-ring
- snatch block
- double pull winch line

If the 9500 lb rating (vs the 29,000 lb rating) was a problem I don't think they would recommend a double line pull like that. Of course, you could always double up the D-ring to be safe.


I think maybe this could be an answer:

http://www.ok4wd.com/index.php/catalog/product/oro_x_ring/

This is a stainless D-ring. The page says working strength 8000 lbs. breaking strength 40,000 lbs.

I would think the standard D-rings could be similar (or even higher).

AG
 

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Something I didn't think about was that D rings are very conservatively rated. I believe the WLL is 1/6 of the designed breaking strength. So even if your load doubles the working load limit of the shackle, you still have a safety factor of 3.

I believe 'WLL' is used more for overhead lifting which has much more stringent ratings than horizontal recovery because of the risk to life. The safety factor of 6 is probably some OSHA requirement.
 

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...and another one joints the winch club.

I went with the Superwinch LP8500. I also got the Curt receiver mount to go with it as a package deal at Carlisle.
:woot:

Now it's time to shop around for some synthetic line. Anyone have opinions as to what sort of line-end I should use. I've seen a few options out there...

Safety thimble:


Crushproof thimble:


Standard thimble:


Self locking:


Spring clippie (per Bill Burke):


Hammerlock or not? Any benefit/ downside?


Any opinions out there?
 

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All the great math lessons aside, the actual force developed by the winch will only equal the weight being winched, up to the capacity of the winch (or the rope, parts, etc.) to pull it. Just because the numbers work out to 16K pounds doesn't mean that much is being exerted. If the vehicle rolls at 2K pounds, that is the force.

Now, get it wedged in a rock garden or sucked mid-door deep in the miry much, and you can generate those sorts of weights rather quickly, but most winch pulls won't exceed 1.5 times the weight of the entire vehicle, in the case of a TrailVoy, somewhere around the 6-7 K pounds range.

Here is another great resource for winching:

http://www.pirate4x4.com/tech/billavista/Recovery/index.html
 

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This is a pretty good little thread going for the newb's... One thing I've noticed during the many times I've unfortunately had to use a winch. (I try not to use them for fun like some of y'all!!:weird::D)


Having 100Ft of line isn't always the best. Keep in mind the insane amount of power draw your putting on your rig while winching. Then think about all the excess line you have to spool back. I've seen electrical systems start smokin, and alternator's die when you really don't want them too!... I prefer a small amount of line, from 25-50FT which keeps it more manageable and keeps the winch performing closer where they rate them, and keep various sized straps to make up for the short winch lead.... (most winches are only rated with one rap on the drum, every wrap after that decreases the pulling capacity!!)
 

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Sez the guy who is hardly EVER more than 20 feet away from the nearest tree. :undecided :rotfl:

Yet 25-50 feet would still be enough since you would be using a pull-pal out there in the land of no trees and you cold place it as close as the oregon trees.
 

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...you would be using a pull-pal...
Perhaps. :undecided But the Pullpal takes 6-10 feet of cable to do its job and dive down for traction, at least the time I used it in deep sand. When Teebes and I were on Wheeler Ridge on decomposed granite, it took him almost an hour of trying different spots 50-80 feet away to find one that bit. But I can see the immense benefit of having a short section on the spool, with a couple of 75 foot extensions in the recovery bag for rigging. :undecided
 

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Interesting... I'm planning to swap out for synthetic line as soon as possible. It sounds like it may be better to get 50' for the spool, and then purchase a 100' extension to go with it.

However... in the rare event of having to rig a pull that is longer than 50' (as my club had to do during a trail clean-up day) you would have to stop every 50' and re-rig. That could become tricky if the load is on a slope and needs to be held while re-rigging the winch.
 

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This is a pretty good little thread going for the newb's... One thing I've noticed during the many times I've unfortunately had to use a winch. (I try not to use them for fun like some of y'all!!:weird::D)


Having 100Ft of line isn't always the best. Keep in mind the insane amount of power draw your putting on your rig while winching. Then think about all the excess line you have to spool back. I've seen electrical systems start smokin, and alternator's die when you really don't want them too!... I prefer a small amount of line, from 25-50FT which keeps it more manageable and keeps the winch performing closer where they rate them, and keep various sized straps to make up for the short winch lead.... (most winches are only rated with one rap on the drum, every wrap after that decreases the pulling capacity!!)
It's been a long long time since my four wheeling days but I seem to remember that the advantage of a Nylon or synthetic line over aircraft cable or God forbid chain was that as the nylon was reeled in it would stretch storing force much as the plates in the earth until enough energy was stored in the line to over come the force holding the stuck vehicle much like an earthquake. Then as the stuck vehicle started to move. the line would begin to shrink back. Hence the name "Snatch Strap" or "Snatch line". Your not really pulling a stuck vehicle out but literally snatching them out. Of course this all depends on evaluating the situation and Knowwhat course of action to take. Sometime a short distance or sometimes a longer distance. But whatever you do DON'T sit in your vehicle while winching a stuck vehicle. Use the remote cable and get behind your vehilce or a tree if possible. A parting line can cause serious injury or even death.
My :m2: from an old timer four wheeler.
 

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Yep. That was the good old days, and recovery straps are still like that. And steel winch cables are still like that.

But the new synthetic winch lines are miracle products, that don't store energy, won't fray in a way that will slice your hand up, and if they break, the cables just falls safely to the ground. The item you're winching might do bad things, but the cable won't snap back or take off a head.

For more reading:

http://128.83.80.200/taco/cable.html
http://oramagazine.com/pastIssues/0411-issue/041106t-winch-rope.html
 

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Sounds like Hal is referring to winching in series with a snatch strap... which isn't recommended these days for two reasons. A, they store energy and have massive recoil in the event of a failure. B, they tend to cause uncontrollable recoveries... as you said, they store energy until the vehicle is through/over the obstacle and then it keeps on pulling the vehicle, which can lead to an extremely lurchy recovery.

As Bill said, today a material known as Amsteel (or Amsteel blue) has been developed from a nautical application to fit the specific needs of static vehicle recoveries.
 

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Yep. That was the good old days, and recovery straps are still like that. And steel winch cables are still like that.

But the new synthetic winch lines are miracle products, that don't store energy, won't fray in a way that will slice your hand up, and if they break, the cables just falls safely to the ground. The item you're winching might do bad things, but the cable won't snap back or take off a head.

For more reading:

http://128.83.80.200/taco/cable.html
http://oramagazine.com/pastIssues/0411-issue/041106t-winch-rope.html
Wow they even have electric start vehicles now too! LOL
:thx Good and enlightening articles. Isn't technology Great.
 
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