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KaiserBill
03-24-2015, 07:21 PM
http://www.allwheeldriveequip.com/images/trucks/975e2e2c-d0c9-462a-b231-830e939c44ca.jpg


The question of winches I think it a very important one. How much winch is enough? Is there such thing as too much winching power? Personally, in the words of Jeremy Clarkson "More Power" is always my rebel yell when it comes to winches!!!! So, let's use a few help rudimentary formulas easily found on the DP Winch Manual for any one of their winches.
http://www.team-twg.com/documents/dp-winch/service-operating-manuals/winch-application-manual.pdf

You'll find on page 12 of the manual referenced in the link you'll find a useful formula: (weight of vehicle * surface drag) + (Gradient Resistance Value * Weight of Vehicle) = Effort Required to recover said vehicle.

So, they have a list of surface type drag coefficients and for example let's use Clay (Clinging) .50 , let's say our vehicle weighs 5,000lbs and our slope of incline is a 100% grade or 45 degree angle. So they calculate the resistance to the gradient at being 1/60th times every degree above 0 degrees. So that leaves us with a .7500015 or .75 gradient resistance coefficient factor. So now we have (5000*.50)+(5000*.75)= 6250 ft-lbs of force required to recover this object from a thick clinging clay up a 100% grade. Which isn't a bad estimate.

In reality you would also want to factor in the the surface area of the vehicle that is contact with the mud. It is very possible that your vehicle is submerged up to the frame in deep mud. Which of course would require more force to extract the vehicle than if it is merely the tires stuck in mud. This is especially true if the vehicle itself has become disabled.


Another factor that is often over looked is the angle of the pull itself. Once you start to pull on the vehicle from an angle that is greater than 20 degrees from horizontal-- such as when the vehicle is stuck at the bottom of a hill and you need to get a steep incline and the anchor point is at the top. If you have 60% grade or 30 degree angle you can loose up to 65% of your single line pulling force. That is because you actually pulling the vehicle up and then forwards. So, that is an important thing to remember when you are out winching your vehicle... the anchor point should be less than 20 degrees higher or lower than the center line of your vehicle.

So, what are your options in these scenarios? Well option is a snatch block(s). Depending on your winches capabilities: 10,000lbs, 12,000lbs, 18,000lbs or greater line pull will determine if your vehicle requires 1, 2, or more Snatch Blocks to self recover from sticky situations. Now, a snatch block doesn't affect the winch lines breaking strength or the winches shear pin. A snatch block or series of blocks will only increase your mechanical advantage. The goal is to maintain a specific line load while increasing the applied force to the object being pulled out. Also the more snatch blocks you use the more cable you pay out and greater the load and be distributed across the wire ropes length. So, if you have one block and you have an 2 x 10,000lbs per length of the line so you support now a pulling force of 20,000lbs. Now, you can use very complex systems with multiple pulley snatch blocks that will allow you take a extremely heavy object reduce the line load to an acceptable amount across the entire length of the line being used. One of the down sides with this system is that if you have 200ft of wire rope (or synthetic) on your drum-- if you use 1 snatch block you're down to 100 feet maximum distance, 2 your down to only 50 feet of useable distance, and 4 will move you down to being only 25 feet away from the anchor or recovery vehicle! But with four blocks you can basically increase your pulling power by a factor of four. So, snatch blocks have their usable limits if you need to make an extremely long recovery.

http://www.4-wheeling-in-western-australia.com/images/winching-DLP-SR3x-Tree.jpg

So, then a bigger winch is the answer? Well, I would say, yes. It is always best to put the biggest winch on your vehicle possible for off road applications or extreme recovery operations. So, if you have a Jeep that weights in at 5,000Lbs or 7,000lbs I would get a winch with a single line pull of at least 2.5 times the gross vehicle weight. This will give you the maximum pulling effort in the most extreme single scenario. Then I would get a snatch block rated for 2 times what ever my winch is rated for. So if I have a 12,000lb winch single pull capability I would want at least one snatch block with rating of 24,000lbs (probably for safety purposes I would go up to 30,000lbs and me I would get 2) and this will keep you safe when you do single, double or triple line pulls.

Now, what sort of power option? Well, I'm a fan of either hydraulic or Engine Driven via PTO (usually on the transmission or transfer case) systems but some run off an engine PTO i.e. Unimogs my self. They offer usually the highest power outputs and have the benefit of not depending on the battery (or batteries to operate). The downside is you need to have the engine operating to work the winch. Or you need to have a secondary power source to run the winches i.e. auxiliary engines. However, that being said you usually get the greatest pulling power with a winch that is either run from an engine PTO or Hydraulic motor driven. These units are usually for very large vehicles or for very difficult recovery operations where maximum single line pull strength is required over the greatest possible distances.

The electric units are great. They tend to top out at 24,000lbs usually (and that is usually only for a 24volt system). The more common 12volt system usually operate at 18,000lbs max. Which usually more than enough to move a truck that weights 4-7,000lbs GVW off road with a single line pull under most circumstances. Under that the 9,000lbs-12,000lbs units I usually consider being for moderate off-road applications. They are for people who aren't going to find out what is is like drive in 30+ inches of mud. Usually one of these units will give the average off-road enthusiast the greatest value and utility from the winch. And the installation of an electric winch is far simpler in a Jeep than a hydraulic or pto powered type unit would be.


As for myself-- I'm putting a DP Winch I won at auction (government) recently that is rated at 25,000lbs low mount for the front of a 5-ton FMVV truck. It is a nice winch. I will need to alter my truck to use a hydraulic system but I got it for like $1800 plus tax with 300ft of wire rope on it. So, I couldn't pass it up. It will be great on "The Duke" with the new CAT3116 in it. I just need to set it up to operate with a hydraulic pump and system. Other then that it will give me about nearly 2 times the maximum single line pulling force of my vehicle when fully loaded and with a series of snatch blocks-- I'm going with 4-- it will be able to pull 100,000lbs almost so... You know I think I have it covered. I really cannot fit a larger unit on the truck in the front without doing major modifications. However, I'm happy with this unit.


It is a pretty meaty winch weighing in at 625lbs plus wire rope and mounting brackets. When completely mounted it should weigh in at about 850lbs with hydraulic reservoir and so on. But it will really increase my off-road capabilities.

JeepLab
03-24-2015, 07:24 PM
key with winches is minimum weight with enough pulling power to get your rig out of whatever you get it into. A pound heavier, and you are doing yourself a disservice.

KaiserBill
03-24-2015, 08:46 PM
key with winches is minimum weight with enough pulling power to get your rig out of whatever you get it into. A pound heavier, and you are doing yourself a disservice.

I disagree with minimum weight. I find that the real factor is calculating your weight of the vehicle fully loaded with the winch on the front and then get a winch that will fit the 1.5 to 3.0 times this weight factor for a single line pull. Because once you have that set up using a snatch block (or blocks) will only give greater potential for winching power under adverse conditions.

One of the last things you want is a winch made of light weight materials that fails while your truck is being recovered. Light weight components often fail you when you need them most. So, if you are 10-20lbs heavier than the lightweight option-- I would take the heavy model with beefier components and forget the 10-20lbs extra in weight. But that is just me.

You also have to remember I'm using 5/8 inch diameter wire rope with a length of 300+ feet. Most other winches for trucks or SUV's that weigh in less than 300lbs have only 90-120feet of wire or synthetic rope on them. Which makes doing a triple or five line pull almost impossible. I like to know that if I want to do a 4 block five line pull I can if I want to.

KaiserBill
03-25-2015, 11:19 AM
I'll have to video the vehicle doing a triple line pull in mud once I get it all set up.

Snarf77
03-26-2015, 08:47 AM
Knowing how to correctly use your winch is about 10 times more effective than having a bigger winch. Triple line pull would be excessive for most of us driving jeeps as we don't need that much pull. My 8000 Engo should be fine for all but the worst situations, where I'd have to be a bit more creative.

KaiserBill
03-26-2015, 09:37 AM
Knowing how to correctly use your winch is about 10 times more effective than having a bigger winch. Triple line pull would be excessive for most of us driving jeeps as we don't need that much pull. My 8000 Engo should be fine for all but the worst situations, where I'd have to be a bit more creative.

No matter what the size of the winch is, you have to use it correctly. Or, you die!!!! Literally actually in many cases as a piece of high velocity wire rope or synthetic cord attempts to take your head off or remove other vital organs and appendages from your person. With that disclaimer out of the way. The reality is that many cases you just don't have the required anchoring point near enough to your Jeep (truck) to allow you to do a double or triple line pull if you purchase a smaller less capable winch. Now, of course these types of scenarios are usually only encountered by the ultra hardcore off-roaders. But, you know it could happen to any one. You can drive into an area with bog type terrain sink the vehicle to the frame and have your anchor point too far away for a successful double line pull. Or you could be stuck at the bottom of an incline and need to use a high degree of angle on the winch. This will as I described above reduce your pulling effort as well. So, you have many occasions where having double or even triple the size you think you need might actually be necessary for a successful single line recovery. And if a single line pull is your only hope of getting out-- you need to have a serious winch.

Remember, usually only use a winch when you are alone in the woods or trail.... So, it is always better to have a system that can reach as far as possible with as much effort as possible than to be stuck in an area with a winch too small and too weak to really get you unstuck.

https://www.youtube.com/watch?v=rEC7HhaAuLM

I've seen trails turn to this sort of condition when I drive over them. Also many a Jeep I've seen stuck in areas like this. You can easily find area with deep mud that you didn't account on. This is you are like me and prefer areas that are more expedition then prepared.

Snarf77
03-26-2015, 10:16 AM
At Rausch Creek off-road park there are plenty of 4-5 foot deep mud/swamp/pit/bog areas that will swallow 44s. While it is a prepared area - you're not allowed to jeep alone. Entry requires a group of at least 2 vehicles for the same reasons you point out (not obvious to everyone). Again - there aren't many east coast areas where you can legally roam free across land where you'd encounter a stuck like the one in your video.

That being said - if you wheel alone, you prepare differently and take fewer risks. The mog in that video could/should have gone around that hole if it were alone. No winch required.

KaiserBill
03-26-2015, 10:28 AM
At Rausch Creek off-road park there are plenty of 4-5 foot deep mud/swamp/pit/bog areas that will swallow 44s. While it is a prepared area - you're not allowed to jeep alone. Entry requires a group of at least 2 vehicles for the same reasons you point out (not obvious to everyone). Again - there aren't many east coast areas where you can legally roam free across land where you'd encounter a stuck like the one in your video.

That being said - if you wheel alone, you prepare differently and take fewer risks. The mog in that video could/should have gone around that hole if it were alone. No winch required.

The Mog actually if you notice didn't need to be pulled or winched out. It made it through the mud pit under its own power. The tow strap had almost no tension on it. My guess is the first truck went through the obstacle then the anchor truck came through it and that is why you saw some tension on it-- as he moved the first truck up to anchor the second vehicle.


Too many cry babies get out and winch it. I'm a big fan of the expedition mode. And hence my desire to go to Alaska.

That being said my point with the Unimog was that you often will find serious mud pits. And often you have few places to anchor itself.

KaiserBill
03-26-2015, 09:34 PM
http://i.ytimg.com/vi/qSl4FkUGh8I/maxresdefault.jpg

Who says your winch is not a multipurpose tool???

KaiserBill
03-26-2015, 10:13 PM
https://www.scribd.com/doc/256696186/Military-Fm20-22-Vehicle-Recovery-Operations

This is a really good manual for self recovery...

Gunner
04-04-2015, 01:05 PM
And don't forget that winches are usually rated on the first wrap of cable on the drum. The more wraps on the drum when you start winching the lower the rated pulling force. Good post.

KaiserBill
04-05-2015, 05:08 AM
And don't forget that winches are usually rated on the first wrap of cable on the drum. The more wraps on the drum when you start winching the lower the rated pulling force. Good post.

That is true. I've never liked the way most winch charts say One wrap- is that one wrap of cable off or on? Intuitively, I always think that is with one wrap off the drum and have to correct myself that it means that maximum pulling is done with one wrap on the drum.

This is another reason to always have a snatch block or two with you. You might need to use them to change your pulling force so you can secure yourself far enough away from the vehicle to use a single line pull of maximum strength. However, with most electric winches for these vehicles you never have much more than 120ft of wire or synthetic rope on the drum.

KaiserBill
04-05-2015, 05:23 AM
The Video of the same photo--
https://www.youtube.com/watch?v=qSl4FkUGh8I

The stump is not exactly that big-- but the winch is probably only 8-9k lbs in pulling force.

KaiserBill
04-05-2015, 05:40 AM
The guy has a nice triple line pull set up. However, he forgot to put damper on the wire rope to keep it from snapping and destroying property and people.

https://www.youtube.com/watch?v=eycJ616L6DU