Recovery Formula...

Are some posts you made missing?

Edit: i must've missed it...

 

several..to include a link or two to another tacoma related forum lol..

 

Hmmmm youd think if they were to take it off theyd let you know why?????? anyone out there got any answers?

 

Only if the slope is 90* would the "Grade Resistance" be the full weight of the vehicle.

 

oh damn that sucks

 

Updated the Pics in the original post hope you guys like em

 

Good stuff "monkeyproof" well thought out. It sounds like some military experience in that diatribe. Couple things: Mire Factor also takes into account the soil conditions - wet, dry, adhesion factors (how thick/thin/wet/dry) compacted clay vs. wet gravel etc. You did lay it out there well. Just need to add in a few more "factors" to complete the equation.

Some winch companies rate their winch at stall point others rate at clean line pull. All winches are rated from the bare drum adding the first layer. You are correct about subsequent layers diminishing the rated pull. Usually the power zone of most winches is the first and second layer. You are also correct in labeling the layers - first is drum side, and fourth/fifth is exterior exposed. Remind your readers that they need to rig the fall with the amount of rope that will get the initial load at the bare drum to start. (we are speaking about Recreational winching and light industrial winching here) In Heavy winching and military winching the equipment may be much higher WLL and Proof Load Tested.

Pulley Blocks DO NOT double the winch capacity - they REDUCE the work effort for said winch.

You are correct in stating that ROLLING resistance is the most common instance for recreational winching except for up-righting vehicles and a Mire Factor above 1.0.

Good job.

see you around, if I do I owe you a pair of Superwinch gloves!!!

Bill Burke

 

when you add a Pulley yes it does double the winch capacity (in a way) i feel i should explain this in another way...

I you have a 10000 lb load to recover and you hook up a pulley you reduce that load by half so i guess it can be misleading by saying that but it is true. This is in many manuals and the military has been using it for a long long time.

if you have a winch that can pull 10000 lbs and you use a pulley, that same winch can now pull a 20000 lb load but it will only be working as if it was pulling 10000 lbs.
The winch doesnt magically gain more power! I hope this is understood by the readers. i just took it for granted that it is understood that the work effort was reduced.

If you add a pulley your winch can pull twice as much even though as far as the winch is concerned it only feels like it is pulling 10000 lbs even though the load is weighing in at 20000. I dont think that the average joe is really concerned with the specifics of these things but you are right...

The winch doesnt magically double its power, the load is reduced allowing the winch to pull twice the amount it originally could have. it has always been referred to as doubling the power of the "pulling unit" though so that is how i purveyed it. Rememeber a "pulling unit" could have been a mule or horse back in the day but the use of pulleys allowed them to pull twice the load they normally could have. (more depending on the amount of pulleys).

A winch will never pull harder than the max load it was rated at. it is impossible. but you can make a really large load SEEM like less to the winch through the use of pulleys

I have to say thanks to Mr. Burke for point that out though because there was probably plenty of people out there thinking they had a winch that was pulling at a rate of 20000lbs, however we know that would be quite a lot of amp draw to get that power and have the winch actually pulling with that much force

This brings me to another topic that we were talking about in the winch questions thread. I may just add this along with an explanation of the doubling or tripling of winch power as a note at the bottom of the post.

You can double the power of the winch or "reduce the work effort" (depending on how you want to look at it) to help out on the power draw. If your winch can handle the load with a one point rigging but it is no trouble to add a block then why not? You will be making the winch pull with less effort and in doing so your winch will require less amp draw which will in turn be easier on your battery life should you not have a very effective power source setup. jsut another tip to throw out there.

Thanks again Bill

 

The original Post has been edited in the section that talks about mire and at the end I added some more stuff that should be very useful to some.

 

Here is the easiest way to explain the pulley. Its just like 4Lo. You pull twice as much weight at half the speed.

I think the formulas are way too conservative, especially the mired formula. Overcoming rocks and ledges? Sure. Mud? Not so much. I have never winched out of snow... does it compact into ice and not allow travel more than mud? Mud moves pretty easy. I had a 35" Swamper over one tire in mud with a CJ7 and it was winched out with no pully and a 8000 lb winch.

 

8000lbs was probqably all it took...was the whole vehicle mired or just a protion of it. what type of mud was it...some mud does NOT move very easy. The situation will always dictate. the formula works, but of course if your mire material is thinner than it is thick than it may not take as much force to recover. This Formula think is not MY invention or anything. it is taken out of technical manuals and field manuals that the military has been using for years or should i say decades so im not going to reinvent the wheel, just going to pass on a little knowledge. would it really be that much more effort to put a pulley in if you think it MIGHT be necessary? but it is a PITA when you have to reconfigure your gear because your set up didn't quite cut it

 

so since i have a smaller 5500lb winch it would technicaly be maxed out on the first roll of wire on a 90o grade.

 

yeah you would really be pushing the limits if your truck is around 5000lbs. if i were you i would use a pulley every time i recovered...no matter what. And use a second for those really bad pulls. you'll burn that winch out in no time if you work it like that for its life and your power supply will be taking a beating for the life of the winch as well. no worries though, just pack a couple pulleys and shackles around.

 

Nice job!

 

Good solid info but if I get stuck, I'm pulling out winch rope and a strap,not a calculator! 6000lb 4Runner/XRC8 100ft synthetic.

 

you dont need a calculator...its not that difficult if youve used it a few times. it just seems that way when it has to be explained. once you know your vehicle's weight you can pretty much do it on the fly. I personally have a 9500lb warn winch so for me one pulley does just about anything i want and keeps the effort from my winch at a minimum not everyone has that luxery though and may need to know some more accurate numbers. nice ride by the way

 

Not sure if it was stated but you shouldn't exceed the winch lines capability.

 

Sub

 

where is the winching pics thread?