Winch snatch block configuration question

[Kwill]

 Got a question on hooking up thee cable from my winch on my logarch. Here is a pic sorry it'd kinda grainy


 
Is this how I want to hook it up to make it pull easier? Winch cable to hook on pulley block. Cable from the anchor point on the corner to the pulley and down to log? Sorry if its confusing

[Magicman]

No, if I am following your drawing that would put twice the pull on your winch.  Run your winch line through the block and then back to the winch or whatever the winch is attached to.  A single line then goes from the block hook to your load/log.

[WV Sawmiller]

   I use a small log arch with my ATV and I use a lot of 1/4" cable and 20,000 lb snatch blocks from TSC or HF. I chain my snatch block to a tree in the direction I want the log to go then hook what you describe as the anchor end to my arch winch. If the log is too heavy for my winch/ATV weight and pulls them toward the log instead of vice versa I anchor the ATV to a tree with the ATV winch or a chain.

   Sometimes I have to move the snatch block anchor point several times to get the log where I can get the winch to it.

    A big advantage of the snatch block is it allows me to use gravity to pull the log downhill with my ATV increasing the pulling weight while keeping it in a safe area. This is especially true if I am using the winch to control the direction of a tree I am felling plus I can stay well away from the range of the falling tree (Always a very good thing).

   Remember - you can use multiple snatch blocks to control direction and in some cases even gain some mechanical advantage.

   I hope this helps.Let me know if you have other questions.

[Kwill]

No, if I am following your drawing that would put twice the pull on your winch.  Run your winch line through the block and then back to the winch or whatever the winch is attached to.  A single line then goes from the block hook to your load/log.

OK thanks. I thought I might have had it wrong.

[Kwill]

   I use a small log arch with my ATV and I use a lot of 1/4" cable and 20,000 lb snatch blocks from TSC or HF. I chain my snatch block to a tree in the direction I want the log to go then hook what you describe as the anchor end to my arch winch. If the log is too heavy for my winch/ATV weight and pulls them toward the log instead of vice versa I anchor the ATV to a tree with the ATV winch or a chain.

   Sometimes I have to move the snatch block anchor point several times to get the log where I can get the winch to it.

    A big advantage of the snatch block is it allows me to use gravity to pull the log downhill with my ATV increasing the pulling weight while keeping it in a safe area. This is especially true if I am using the winch to control the direction of a tree I am felling plus I can stay well away from the range of the falling tree (Always a very good thing).

   Remember - you can use multiple snatch blocks to control direction and in some cases even gain some mechanical advantage.

   I hope this helps.Let me know if you have other questions.

OK thanks for the info.

[Idiocrates]

Snatch block is a simple one block block and tackle system so remember you'll be rolling up twice as much cable as the distance the load will be moved...in other words, to move the load 50' you'll have to wind up 100' of cable. If the length of cable on the winch is insufficient to reach the load you can use a separate cable or chain between the hook on the block and the load.  And remember, You can build a block and tackle out of multiple snatch blocks but it gets pretty cumbersome trying to keep the cable tracking properly in all the blocks.

[Kwill]

Snatch block is a simple one block block and tackle system so remember you'll be rolling up twice as much cable as the distance the load will be moved...in other words, to move the load 50' you'll have to wind up 100' of cable. If the length of cable on the winch is insufficient to reach the load you can use a separate cable or chain between the hook on the block and the load.  And remember, You can build a block and tackle out of multiple snatch blocks but it gets pretty cumbersome trying to keep the cable tracking properly in all the blocks.

yeah im just using it on my log arch to lift the logs off the ground.

[WV Sawmiller]

Kwill,

   Thinking back on it I have used the configuration shown in your drawing only instead of a winch I hooked that snatch block up short to the front of my trailer then when set up I'd slowly drive forward  which forced the log up on to the trailer. Use caution and make sure you are hooked to a very strong/secure point on the trailer and  be sure to stop just before the log reaches the snatch block or you will bend your trailer or tear up your snatch block (Don't ask me how I know that ;D). It is a hard pull but has it's applications. Works best with a helper to stop you at the right time and sometimes to rock the log with a cant hook if the log wants to hang on a root, rock or the lip of the trailer or such. Be sure you are not pulling while your helper is rocking the log as the tension on the cable can be high and you or your helper don't want to be in the area when one breaks.

[WV Sawmiller]

   Attached below is a very rough drawing showing the 3 applications of snatch block (SB) use to load logs I discussed above.

   1st drawing shows using one SB to direct the pull of a log using a log arch, tractor, ATV, etc.

   2nd drawing shows use of 2 snatch blocks for multiple direction changes using a log arch, ATV, tractor, etc.

   3rd drawing shows how to use a snatch block to load logs on to the end of  a trailer. In this case the truck attached to the trailer pulls the log into the trailer. Requires use of a tailgate or loading ramps to slide the log from the ground up into the trailer.

   Not shown is how to use a cable and snatch block to parbuckle a log over the side of a truck or trailer. Requires use of an anchor point opposite the logs on the other side of the truck or trailer and another piece of equipment to pull the log up an incline (usually 2-3 logs or pipes or such)

   Hope this helps clarify what I said earlier.

[Kbeitz]

 

 

[WV Sawmiller]

Kbeitz,

   Yes but that is a block and tackle arrangement with multiple grooves to wrap rope/cable around multiple times and they do let a little person pick up a very heavy load.

   The snatch blocks I am referring to are single groove and I use them primarily to direct the log in a specific direction. In some cases when using multiple snatch blocks I may gain some small mechanical advantage but that is not my primary goal.

   BTW - thank for the diagram. I recently replaced the rope on my deer pulley and am going to go make sure I wound them right.

[Kwill]

OK I got my winch today. Going to try a couple different configurations and see which works best

[Kbeitz]

Another way to go is with a two speed hand winch.

[WV Sawmiller]

Kwill,

   BTW - are you using the snatch block with a cable to direct the log or with the winch as a pulley to lift the log? On my log arch I use Fairlead rollers. I use a UTV winch after finding my ATV winch was too small as was the 2500 lb hand winch.

    The pulley will reduce the friction and increase lift but you have to have the arch point directly at the log or it will twist and bind. The FL rollers accommodate such issues better.


 
   My arch will likely be way different than yours but you can see the FL roller placement. My arc is light enough to pull up pretty steep hills with my ATV. Once I hook the arch to the log or cable hooked to the log and start taking the slack out the arch will slide over till it is straight on line with the log. Or sometimes it will start to tilt over on one wheel and I give it slack and slide it by hand till we have a straight pull.

[Dalrymple]

OK I got my winch today. Going to try a couple different configurations and see which works best

Kwill, on my arch, and many similar, the winch is mounted up front and the cable runs horizontally back to a block and down underneath the log and back up to anchor on the arch on the opposite side from the block.  This configuration pretty much allows lifting twice the capacity of the winch.



Some example illustrations for using snatch blocks for self recovery and/or moving objects...

Basic single line pull.  Let's say the winch is capable of putting 10,000 pounds of pull on a single line.  In this example, we can apply 10,000 to the winch (or vehicle) and 10,000 to the object.  Whichever moves easiest, moves.


Basic double line pull.  Same winch capacity.  In this example we can put 20,000 on the object and 20,000 on the vehicle.  Again, whichever one is easiest to move, moves.  An important point though, the winch still only sees 10,000, while the tow hook or other anchor point on the vehicle sees the other 10,000 and the vehicle as a whole sees 20,000.


This is a triple line to move an object such as a large log.  The winch and vehicle in this example only see 10,000, the tree beside the vehicle shoulders 20,000, while the one out front sees 30,000 and likely moves.


To keep it all straight in your mind, simply count the winch lines.  The winch can put 10,000 ( or 8,000 or whatever its capacity is) on a single line.  This is all the load the winch should ever see.  The snatch block shares the load from each of the winch lines coming to it, so when the winch puts 10,000 on its single line, the snatch block transfers it around the sheave and sees 10,000 on each of the two lines.  The snatch block and its rigging must be strong enough for double the winch single line capacity.

Triple lines? Or more?  Count the lines, multiply by winch capacity, be careful what you anchor to and how.  I've run 6 lines to a single black locust about 24" in diameter, hooking 20' up in the tree, using multiple surrounding trees for anchors.  With only a single line from my F150 and 9,000 winch I didn't even have to tie the truck down to uproot the tree.  Takes extra cable and some time to rig, but it works.

[Magicman]

Edit:  My apologies, I failed to read/understand where your load was in the third example.   :-[

[Kwill]

My winch is mounted at the front of the arch. I'm hoping to get it all hooked up tomorrow so I can try it out.