This is somewhat a continuation of my thread from last winter (here). I am building up my arsenal of equipment and have a question on the winch lines.

The winch I got is a Talon 18.0SR. It has 90ft of 1/2" line. The road we were on last winter, specifically the area we were digging out a pickup, was pretty wide where the trail is. When I used my hand winch I tied as many straps and chains together as I could otherwise we would be pulling the truck sideways - and we just wanted to get it bacbk in its tracks which were right behind it, not to the side. So that was one problem, but the hand winch and block was not nearly enough to extract it. It took shovels and a lot of pushing instead.

So on the subject of getting the right angle on the winch line to get the vehicle to go the right way - what thoughts do you have? In my case last winter - if I was to get a straighter pull I would have to add a lot of line. I don't know even if 90ft (really, less than that because there needs to be a few wraps on the spool) would be enough. Yeah, there are trees around, but none close in the right spot to get a relatively straight pull.

There are two schools of thought I see in this case. 1. Run an extremely long line to an anchor that is in the right spot. 2. Use cross lines between 2 anchors that will position the point the winch line attaches to at a more appropriate angle.

Route 1 would require a pretty long extension. Route 2 would require 2 lines as the joint between would be needed to attach the winch line to (as opposed to one line and the winch line hooked somewhere = no way to secure the hook from moving around like it would be locked in loops on 2 lines).

I have 3 sets of tree straps, shackles, and blocks coming also. Something I considered with the 3 sets is if I had a long extension line and had a situation that required lowering a vehicle (brake power as opposed to pulling power) I could use the second vehicle as the anchor/brake (rolling) as opposed to letting line out on the winch. An extension plus the winch line may give enough "running line" to make it through a run of blocks and still allow for a controlled descent.

 

If you do something like this make sure the "cross" line is WAY longer than it needs to be to reach between the two anchors. You need the resulting cable setup to look more like a "Y" than a "T". Otherwise the tension in the cross cable will be A LOT higher than the tension in the main winch line. Without geting into the math details, if the angle between the two secondary lines is greater than 120 degrees the secondary cable tension will be higher than the main cable tension (even though it's being shared by both secondary cables). And as that angle approaches 180 (as it get's close to a "T") the tension in the secondary cable approaches infinite.

 

Yep. I know what you mean. I remember calculating vector forces in physics class. The idea is to make a "triangle" where the third point is where the winch attaches to. By having 2 sides of the triangle not fixed (adjustable - add/remove as needed) the point the winch line attaches to can be adjusted for a sufficient angle of pull.

 

I run 150 feet of cable on my wheeling rig, and frequently use most of it, I carry another 60 feet worth of strap as well.
I find that most of the time only a small tug is required and even with a poorly angled pull you are mobile again before it starts to pull the truck sideways.

 

I'd sooner rig it like this



Rope runs from vehicle, through ****** block (which is anchored to line coming from point B) and to point A.

 

Thanks for the diagram, rovernut. That is certainly another idea to throw in the bag of tricks.

I think the big challenge is how to make use of what anchor points there are. The rigging will have to be matched to the situation, and no two situations will be alike.

I am pretty confident, though, that the stock winch line is pretty short and limited for what I may run in to. I have some straps and a g70 3/8 chain that may give me about 50-60ft if I had to try that, but Id rather plan ahead and make up some proper extensions for the winch line.

 

This is a MUCH better idea. Using a ****** block and running the winch line through it to one of the anchor points limits the tension in that "leg" to what the winch can pull (kind of obvious, since it's the same cable). The tension in the other "leg" (running from the ****** block to point B in Rovernut's sketch) can have more tension than the winch line, but the most it can have is double the winch line tension, and that would only be if you ran the winch line straight back to the vehicle.

My point here is that it isn't always obvious how the force vectors that we talked about earlier work, and with a fixed point connection at point C it's possibly to get way more force than you might expect in the secondary cables. Using a ****** block there really helps limit the worst-case scenario and makes it a lot more obvious what the resulting forces will be.

Still be careful though, because the tension in that B-to-C leg can be higher than the winch line tension if the angles aren't so good (with the angles shown in the sketch the tension in the B-to-C leg would be less than the tension in the winch line, but if the winch line ran through the ****** block to point B, then the secondary cable from A to C would have more tension than the winch line)

 

So in the case of the diagram - what do you do if you are 150-200ft from anchor B? Attach the winch extenstion through the block with the winch line attached to the extension? Or forego the block and run a couple lines to both anchors with the extension off the ends (where the block is in the diagram)?

 

Either one can work. But using a ****** block, even if it means you have to hook an extension to your winch line, will allow the force vectors to balance themselves out the best way possible. As I said above, the benefits to this are that it limits the tension in one of the legs to the winch's capacity, and that it limits the tension in the other leg to only twice the winch capacity while making it a little more obvious what the vectors are actually adding up to. You can rig it safely wit ha fixed point, but you can also rig something that could have much more tension in the legs than the winch is pulling (if you get the vectors lined up badly).