Snatch Blocks for Deuce winch

[Akicita]

I just received the snatch blocks I had ordered online - and they are too small. Looks like I have the standard winch cable on my M35A2 (looks like 1/2 inch), and the blocks I just unpacked are for 3/8 cables.

Before I order more of the wrong size, should I order 1/2 inch or even a bit larger? I searched the manuals but didn't find any reference to the cable size. I want 10,000 lbs pulling capacity at a minimum.

I have used the winch on my truck many times but have no hands-on experience with snatch blocks yet. I need to pull over a dead maple tree and drag it a bit closer to the road (about 100 feet straight pull).

Any and all comments are welcome. I'm new to "snatch blocking".

 

[porkysplace]

These are the TM's you want to study.

[h=1]Recovery and Battle Damage[/h]
[h=1]Towing & Rigging, Misc. TM's...[/h]

 

[BEASTMASTER]

pick up a couple 10 -15 ton blocks and that 'll take care of you ..........

 

[cattlerepairman]

You need pulley grooves and pulley diameters that will fit the 1/2 inch wire rope that you have. Too small and the bending radius is too sharp and the grooves can crush the wire rope. Ideally, you get a snatch block or "sheave" that is for 1/2 inch cable/wire rope. 5/8 will work but I would not go any larger. Unneccessarily heavy and does not guide the smaller cable as well.

It is important to understand how the forces are applied when using snatch blocks. When using a single snatch block that you attach to the load you are pulling and the cable runs from the winch through the snatch block and back to the anchor point (which could be your truck or a tree etc.), then you have the pulling power of your winch (5 tons/ 10,000 lbs) on each leg of the cable. You have 2x the pulling force of your winch at the snatch block and at the chain that attaches the snatch block to your load. Select chain , shackles etc. accordingly! They will need to be rated for a safe working load of 10 t / 20,000 lbs at least.

 

[Akicita]

Excellent resources! Just what I need.
Thank you, Porkysplace.

 

[Akicita]

Yes, gotcha, Cattlerepairman.
Thanks for your replay.

 

[zebedee]

I think I have one of what you speak! Will do you a good deal!! PM if you want to "hook"-up.

 

[fasttruck]

Ratio cable to sheave is 12:1. If you have 1/2" cable you need at least a 6" sheave. A WW truck is issued 1 block, utility chain, a hammer, and punch above what a WOW truck gets. The hammer and punch are to drive out broken shear pins. If I was going someplace where I might get stuck I would bring more than 1 block. A block can do 3 things, although only 1 at a time develop mechanical advantage, change the direction of the pull or be a trolley.

 

[rustystud]

Ratio cable to sheave is 12:1. If you have 1/2" cable you need at least a 6" sheave. A WW truck is issued 1 block, utility chain, a hammer, and punch above what a WOW truck gets. The hammer and punch are to drive out broken shear pins. If I was going someplace where I might get stuck I would bring more than 1 block. A block can do 3 things, although only 1 at a time develop mechanical advantage, change the direction of the pull or be a trolley.[/QUOTE]

Actually it can do two things at once. It can add mechanical advantage and change the direction of pull if you anchor it away from the pulling winch. Not trying to be an a$$ , just saying.

 

[jasonjc]

Here's a video that will show you the power of using block and tackle.

https://www.youtube.com/watch?v=vM24klVyxFk

 

[rustystud]

Here's a video that will show you the power of using block and tackle.

https://www.youtube.com/watch?v=vM24klVyxFk

This is a great video showing the power of pulley multiplication to move objects. Just like our ancestors did back in the day .

 

[zebedee]

Too much going on in that vid - would like to see a diag to understand the 45:1 ratio. The last line would have to go one heck of a long way to multiply for that ratio!

 

[fasttruck]

Reference is made to post 9: in order to get mechanical advantage a block has to move. If you count the capstan of the winch as a block and you establish a stranding block somewhere else and do not come back to the truck and you are not trying to winch the truck out of a hole then you have only changed the direction of the pull. Attached pic illustrates changing the direction of the pull and develolping mechanical advantage at the same time but it uses two blocks. Objective was to pull van out of a line of vehicles. Truck with winch is off camera to the right. Cable goes through first block attached to anchor point green truck. Second block is attached to load and brought back to anchor point, the running block which moves when the cable is taken up. Pic shows rig almost closed up or soon to be chock-a-block. Just saying.Second pic shows change of direction: object is to move car on left to the front of the truck with the winch. Change of direction block is in foreground second block, the winch capstan is also stationary so rig winches work away from truck not towards it.

 

[rustystud]

Reference is made to post 9: in order to get mechanical advantage a block has to move. If you count the capstan of the winch as a block and you establish a stranding block somewhere else and do not come back to the truck and you are not trying to winch the truck out of a hole then you have only changed the direction of the pull. Attached pic illustrates changing the direction of the pull and develolping mechanical advantage at the same time but it uses two blocks. Objective was to pull van out of a line of vehicles. Truck with winch is off camera to the right. Cable goes through first block attached to anchor point green truck. Second block is attached to load and brought back to anchor point, the running block which moves when the cable is taken up. Pic shows rig almost closed up or soon to be chock-a-block. Just saying.View attachment 757716View attachment 757717Second pic shows change of direction: object is to move car on left to the front of the truck with the winch. Change of direction block is in foreground second block, the winch capstan is also stationary so rig winches work away from truck not towards it.

Sounds good to me.