Log Winch Question

[Billbob]

I'm rebuilding my homemade log winch and decided to add in a lower pulley or snatch block.  I got into a debate with my brother in-law about whether or not both the upper and lower pulleys put the winch capability into a mechanical disadvantage.  He says it does, I say it doesn't.  I was always of the understanding that adding a pulley gives more pulling capacity.  Given my brother in-laws very advanced mathematical skills and my considerably pathetic mathematical skills I didn't press the issue with him.  I told him that I was going for a second opinion.  Which is where you folks come in.  Please educate me here.  Did I waste my time and materials building a lower pulley?
Bill

[Hilltop366]

Other than the slight bit of loss from turning a second pulley I can't see how you would loose any pulling power, the lower pulley on the winch I used was handy to lower the pulling point when driving the tractor it helped keep the front wheels on the ground.



 

If the second pulley was attached to the log and the winch line cable went through the pulley and attached back to the winch it would double your pulling power and reduce the log speed in half.

[Brian_Rhoad]

Lowering the pulley will put less lift on the log causing more friction and a harder pull.

[Rockn H]

A pulley is basic physics and can provide a mechanical advantage.  Block and tackles have been used forever to move heavy objects.   A pulley can also just be used to redirect or "guide"  the cable.
In the image below, you'll notice that the snatch block on the left is attached to the roof and is just used to redirect the cable.  How the pulley is used makes the difference.   The imagine on left, to lift the weight one foot, you'd have to pull in one foot of rope giving you a 1:1 ratio or no mechanical advantage.  The image on the right, to lift the weight one foot, you'd have to pull in two feet of rope giving you a 2:1 mechanical advantage.   


 

[Billbob]

If the second pulley was attached to the log and the winch line cable went through the pulley and attached back to the winch it would double your pulling power and reduce the log speed in half.

  The image on the right, to lift the weight one foot, you'd have to pull in two feet of rope giving you a 2:1 mechanical advantage.   

Lowering the pulley will put less lift on the log causing more friction and a harder pull.

Ok, I get it now.  If I put a snatch block on the log, ran the line from a fixed point (the winch) to the snatch block and back to the fixed point on the tractor then I've doubled my pulling capacity.  But running it over two pulleys to the log creates a friction point or drag at the pulleys thereby reducing pull capacity.  So adding the second pulley didn't give me a pull advantage other than the fact I mounted in directly in line with the lower arms on the tractors 3 point hitch having a 'pull' use the full weight of the tractor in line with the tractor and less stress on the top link.  Correct or do I have it messed up?!

At any rate I put on a 13,500lb capacity electric winch.  Added a second deep cycle marine battery with lots of reserve mounted at the winch.  I think that will be plenty of power.  The old winch was a 8000lb Warn M8274 which I bought 34 years ago second hand.  I had it on three different vehicles and it's been my log winch for the past 14 years.  It lasted that long and I figure it doesn't owe me anything.

[thecfarm]

I won't argue which is better,but this is my Norse winch.



 

They design a pulley on top and than another one lower.

[Billbob]

I won't argue which is better,but this is my Norse winch.
They design a pulley on top and than another one lower.

I only have experience with Farmi winches but Norse is a good make also.  If I had my druthers I would have a PTO winch but I gotta go with what I got.  It's not like I'm doing any serious logging.  Just enough to keep the sawmill fed.

[thecfarm]

And a pocket full of 100 dollars bill.   : We brought ours back in '93. When things was not so stupid high.

[Ford_man]

The lower pulley will give less chance of tipping over the tractor when pulling to the side.  

[thecfarm]

Oh no it won't!!!!
I cut a small tree,maybe 6 inches across,I fell it 90° to the woods road. Forgot why,maybe only way for it to go? I just stopped in the woods road and hooked up to it. It was real small,it will handle it easy.    :  I started to winch it to the tractor,got caught on something,root,rock,so I pulled on the rope harder. By the time I came to one side of the tractor was up in the air pretty high. I know it just about bounced when I let go of the rope. I knew better and I know even better now.

[Dave Shepard]

My Farmi has the upper and lower blocks. Try pulling line out from the top, then run it through the bottom to see how much harder it is. I don't think it is going to make a significant amount of difference. You might notice the difference spooling it out by hand, but that only means a few pounds of force on something capable of generating thousands of pounds of force.

thecfarm, if you had been running the line through the upper block, then you probably would have tipped the tractor over if you managed to tip it up running through the bottom.

[thecfarm]

I have not changed the way it is in the picture since we brought it. It does have a place that I can lower the pulley about 6-8 inches lower, but never have. I always run through the top pulley and then the one below it, that lower ones swivels too.
dummy me,no more 90° pulls.     :  As I said,I knew better. Famous last words.

[Dave Shepard]

I seldom use the lower one, but also seldom pull from the side. I've had my Kubota up on one rear wheel before. I guess that's why they give you the long rope. :D

[shinnlinger]

Bill bob, 
I would like go see a pic of your setup if possible. 
Thanks,

Dave

[Billbob]

dummy me,no more 90° pulls.     :  As I said,I knew better. Famous last words.

That's how I burnt the winch out...doing a 90 degree pull.  I made the mistake of letting some logs lay in the snow overnight and they froze in a bit.  Pulled my 6000lb tractor off the ground on one side.  By the way my wife refers to me as 'Jethro'!

[Billbob]

Bill bob, 
I would like go see a pic of your setup if possible. 
Thanks,
Dave

Dave, give me a couple more days and I'll get some pictures for you.  It's laying in pieces on the barn floor.  I have a couple of more things to fabricate then put it back together.

Bill

[thecfarm]

Billbob,make a skid plate for it so the plate will dig in when you are winching.

[Billbob]

Billbob,make a skid plate for it so the plate will dig in when you are winching.

I was going to, then I wasn't going to.  Now I'm going to.  I had the problem on a couple of heavy pulls with the tractor being pulled.  I knew I needed the skid plate.  Just being lazy and impatient I guess.  But I know it's the thing to do.  My afternoon in the shed just got longer. Thanks for lighting a fire under my butt!  : :laugh:

[thecfarm]

One more thing you might want to do. On my guard,you can see the chains hooked on it,than there is a box about 6 inch square and high that the end of the chains go in. I hook the chains on the top of the guard than about 4 feet down is the box and 4 feet of chains is in the box. This way I can make sure I have all my chains,if I check, : after I get done winching or unhooking.



 

[Billbob]

One more thing you might want to do. On my guard,you can see the chains hooked on it,than there is a box about 6 inch square and high that the end of the chains go in. I hook the chains on the top of the guard than about 4 feet down is the box and 4 feet of chains is in the box. This way I can make sure I have all my chains,if I check, : after I get done winching or unhooking.


 

I have the exact same thing on mine. A couple of weeks ago I had to add another 6 inches to the box.  Wasn't deep enough to hold all the chain.  I was backing up the tractor in the woods, didn't notice that a chain end had fallen out of the box and the tractor tire rolled over it.  Tore the chain holder right off the side of the winch!  >:(

[Stephen Alford]

   Hey Bill while your gluing steel add a piece of receiver stock so you can mount a vise. Huge come ahead when you work alone.   


 

[Billbob]

   Hey Bill while your gluing steel add a piece of receiver stock so you can mount a vise. Huge come ahead when you work alone.   


 

Well Holy Snappin' Turtles, Margaret!!  :laugh: I would never have thought of that.  That would be great for holding the chainsaw when sharpening the chain.  I have the receiver stock so I'll put one on tomorrow.  By the time I'm done the winch will weigh more than the tractor!

[Billbob]

Finally got the log winch rebuild completed and used it today to yard about 25 logs.  Worked great.  Lots more power than the old winch.  I added a 13,500lb winch (that has a lifetime warranty!), an auxiliary deep cycle marine battery, peavey holder, lower snatch block, and a skid plate which came in real handy today on a very heavy pull. (thanks for the suggestion TheCFarm!)  And a 2" receiver block for future addition of a removable vise (thanks for the suggestion Stephen Alford!) I even got ahold of a pair of old pallet forks.  So I made a quick detach mounting bracket for the tractor FEL.  I'm 1/2 way through a fabrication on a hydraulic thumb for the pallet forks.



  

  

 

Winch connectors to the tractor battery.  2 gauge welding wire for the battery connections. 

 

Quick detach pallet forks.  Hydraulic thumb in the near future.

 

[thecfarm]

Looks good. I myself would not like the saw on the winch. The big ones stay low if you have to back up,the small ones will ride up.I built a new back for mine,chain holders and all. Looked good. I think 2 weeks later I had a 6 inch tree on and had to back up for some reason. I bent the brand new back. Man was I mad at myself.Still am every time I look at it.  I took billm idea and mounted it on one of the loader arms,right as I get off the tractor. And that way too,I know where my saw is. I also made up some 4 foot chains too. Much easier on the small stuff than an 8 foot chain.I also kept a couple pieces of old cable. Somewheres around 50 feet each. One end has a short piece of chain to hook onto a chocker and I have 5 chokers on that. I run 6 chokers on my winch. Sometimes I use all 6,but most times I don't. Does come in handy to have 6. If I don't use them all,the ones I don't use are not in the way.

[Billbob]

Looks good. I myself would not like the saw on the winch. The big ones stay low if you have to back up,the small ones will ride up.I built a new back for mine,chain holders and all. Looked good. I think 2 weeks later I had a 6 inch tree on and had to back up for some reason. I bent the brand new back. Man was I mad at myself.Still am every time I look at it.  I took billm idea and mounted it on one of the loader arms,right as I get off the tractor. And that way too,I know where my saw is. I also made up some 4 foot chains too. Much easier on the small stuff than an 8 foot chain.I also kept a couple pieces of old cable. Somewheres around 50 feet each. One end has a short piece of chain to hook onto a chocker and I have 5 chokers on that. I run 6 chokers on my winch. Sometimes I use all 6,but most times I don't. Does come in handy to have 6. If I don't use them all,the ones I don't use are not in the way.

The saw is mounted so that when the winch is at full height it doesn't hit anything.  I've been using the log winch for 14 years and never had a problem.  That being said when you're dealing with machinery anything can happen.  I have a bunch of chains and cables as well.  Always comes in handy!  I only haul one log at a time.  Since it's an electric winch I don't want to overtax it.  If it was a PTO winch then it would be a whole different ball game.