Snatch Blocks - Which one? (1 Viewer)

[weigellj]

Looking at buying a snatch block due to the fact I am stuck with a Warn 8000LB winch on the front of my FJ-80 LC and it struggles.

Of course there are several out there.

I am leaning towards the ARB 9000 vs the design of a ARB 7000 or similar snatch blocks on the market:

Snatch Blocks | Products | ARB 4x4 Accessories

Any advise on to which one would be better, or are both designs equal? Any gripe about either?

 

[-Spike-]

What are those, cooling vents?

Winch Accessories - Greg Smith Equipment Sales, Inc is where I'd buy. Specifically Atlas Pulley Block - Greg Smith Equipment Sales, Inc or Atlas Heavy Duty Pulley Block - Greg Smith Equipment Sales, Inc

 

[greentruck]

Looks like Greg Smith has some good prices on stuff. I'll bookmark that for later reference.

Here's something from my bookmarks:
Material Handling-Lifting, Hoisting, Pulling

I bought some of the BLOC 1240s from Allen. They are identical to Warn snatch blocks, although Allen calls them yarding blocks.

 

[Josie'sLandCruiser]

Hi All:

The ARB 7000 works fine, and is much cheaper than the 9000 comp model.

Check out Four Wheel Parts; chances are you will get the lowest price from them.

I dunno about those parts sold on that Greg Smith website; the low prices suggest low-end imported parts.

Regards,

Alan

 

[Layonnn]

Hi All:

The ARB 7000 works fine, and is much cheaper than the 9000 comp model.

Check out Four Wheel Parts; chances are you will get the lowest price from them.

I dunno about those parts sold on that Greg Smith website; the low prices suggest low-end imported parts.

Regards,

Alan

x2

The heavy duty model is rated for a 17K lbs winch, so that means that it should at bare minimum be rated for a 34K lbs load since using a snatch/pulley effectively doubles your pulling capacity. Not to mention the size of a shackle you are going to need for that much load.

I would want a much bigger, heavier duty shackle than that for a 17K lbs winch.

 

[e9999]

warn has some pricey heavy duty blocks (the round red affairs) but I found identical ones (at least outside) with no big names on at much lower cost on the web. YMMV.
I have the 24K Warn one. But disturbingly, IIRC the rating stamped on the block itself is less than what Warn says it is. When asked about that they mumbled something like they tested it and it didn't fail... mmm....

Fair amount of confusion (and misleading figures?) out there on hardware like that.

 

[greentruck]

The Allen Machine BLOC 1240 is the same as the Warn 15640. It's stamped 4.5 tons, but that is WLL. As Warn's description indicates, it seems plenty adequate for use with a 12k winch. Different numbers from different ratings, same capacity.

The big one was just too big to bring a pair along and overkill anyway IMO.

 

[e9999]

The Allen Machine BLOC 1240 is the same as the Warn 15640. It's stamped 4.5 tons, but that is WLL. As Warn's description indicates, it seems plenty adequate for use with a 12k winch. Different numbers from different ratings, same capacity.

The big one was just too big to bring a pair along and overkill anyway IMO.

the point is that it is very dubious IMO to advertise a piece of machinery that is rated at, say, 4.5 tons WLL, as being a 12 tons-suitable contraption in ads. Sure it may go 12 tons without breaking but WLL means just that, that it's intended to work at 4.5 tons, not 12.
I would expect ad inflation like that from HF etc but not from a major reputable company. And in fact, the Allen company does list it as a 4.5 tons on their site, not 12, unlike Warn which does not mention the 4.5 anywhere that I've seen.

 

[greentruck]

Think of the discrepancy this way. It likes measuring distance by miles or by kilometers. You travel a certain distance, but you still end up with two different measurements of how far.

12k is done one way and is the way winch makers rate capacity. 4.5 ton WLL is a different way to measure rigging capacity. Either way you cut it, you should be OK when using the block with a 12 k winch.

 

[Dell]

ARB 9K

 

[opie74]

WLL is derived by a safety margin. Most of the steel materials used in winch products carry a 4:1 safety margin. Some carry a 5:1, but the majority are 4:1. Take the hooks most everyone is using, whether they be Yoke, Gunnebo or Excel... The ones I use are Yoke...



They carry a WLL of 7,100 pounds. However, almost everyone I see that advertises them posts their tensile strength. These have a 4:1 safety margin. So if we are going to go off WLL alone, the 3/8 sling hook that the majority of people use on their winches is not suitable to be used with even 5/16 line. WLL are a major factor in overhead lifting where the danger of death from failure is more common and likely.

Most items that have a WLL are tested repeatedly at 1.5 times their advertised WLL. Dont get caught up in the WLL of an item. If it has a posted WLL, that is not its ultimate capacity and most of the time is better for at least 3 times its WLL. No one is going to post a WLL that is anywhere near its tensile strength.

I realize this is getting into the fine line of safety and reality.... But if you want your recovery gear to to have a WLL of the tensile strength of the line you are using, you are going to need to upsize quite a bit. For instance, in order to have a hook with a WLL of around 18,000 pounds, youll need a 5/8", grade 80 hook. You can step up to grade 100 or 120 and stay with a smaller size, but youre getting into big bucks and not as much availabilty in the smaller sizes.

EDIT: some of this post is my opinon. The numbers are fact.

 

[greentruck]

Opie,
Thanks for the detail on how WLL is a different rating than the way winch ratings are stated. Like you say, the differences are a matter of definition, not a numbers game. And it's a matter of understanding the application of ratings, too.

One thing that has helped me with sizing such things up is having broken a lot of things when I was young. Gave me a certain appreciation for the practical way to size things up so to not break them -- once I got smarter
I suppose I can take an optimistic view of this sort of education since I still have all my body parts intact. But it is good to pay attention to these things, as e9999 reminds us.

 

[opie74]

Green, thanks. Many of the numbers used by companies that offer recovery related products are tensile. Very few advertise the WLL and I believe its because when you hook your winch or recovery line to something and use it, you, the end user, dont know exactly what load you are placing on the line. Unless youve got a load cell somewhere in the mix.

If we were to apply a saftey margin to our winch lines of 4:1 like the hooks, in order to get a line with a WLL of 18,000 pounds we would need 13/16 Amsteel Blue. 13/16 carries a mimimum strength of 73,800 and would cost about $1300 for a 100' line. Or you could go with a 3:1 which would be 3/4 Amsteel Blue with a minimum strength of 54,000, that would run right around $900. Ive figured those prices based on the formula I use for the winch lines I have offered on my site.

 

[e9999]

yup, if you take my M12000 for example, it is (obviously) rated at 12,000 lbs by Warn. Presumably one would expect that it would be capable of exerting a force of 12000 lbs on an object. Well, IIRC, the type of 3/8" line that it came with is standard rated at about 12,000 lbs breaking strength (*NOT* WLL). Which would imply that if you use the winch at its max rated capacity you are right on the edge of breaking your line. Not a comforting thought... Unless of course the 12,000 lbs winch cap is a pipe dream... Or their 3/8" line is a superduper one outside of normal ratings.
Clearly, many of these companies play loose with words in advertisement, counting on people's lack of knowledge to get away with it. Of course, nothing new there...
But throw in the fact that most people out there (and some here ) still don't understand that if you use a block, you can now exert 24000 lbs on what your block is attached to, and things can start to add up in a bad way quick...

Be safe out there!


(Interestingly, I saw that Warn has recently added a little twist in their description of my block. Something about a 12,000 lbs winch but with a 7/16" line IIRC. Getting a bit more careful are they...?)

Clarification: I think Warn is a great company btw, with excellent customer service. It's actually because of my extremely high opinion of them that I was taken aback by their playing a bit loose with some of these numbers. Still, perhaps the best out there and I'll buy again from them.

 

[Southeast Overland]

What Opie said - he beat me to it. WLL and tensile strength are two different beasts. Think of the difference between hanging from something (it breaks you die) vs pulling on something (it breaks no more pulling).

WLL is derived by a safety margin. Most of the steel materials used in winch products carry a 4:1 safety margin. Some carry a 5:1, but the majority are 4:1. Take the hooks most everyone is using, whether they be Yoke, Gunnebo or Excel... The ones I use are Yoke...

They carry a WLL of 7,100 pounds. However, almost everyone I see that advertises them posts their tensile strength. These have a 4:1 safety margin. So if we are going to go off WLL alone, the 3/8 sling hook that the majority of people use on their winches is not suitable to be used with even 5/16 line. WLL are a major factor in overhead lifting where the danger of death from failure is more common and likely.

Most items that have a WLL are tested repeatedly at 1.5 times their advertised WLL. Dont get caught up in the WLL of an item. If it has a posted WLL, that is not its ultimate capacity and most of the time is better for at least 3 times its WLL. No one is going to post a WLL that is anywhere near its tensile strength.

I realize this is getting into the fine line of safety and reality.... But if you want your recovery gear to to have a WLL of the tensile strength of the line you are using, you are going to need to upsize quite a bit. For instance, in order to have a hook with a WLL of around 18,000 pounds, youll need a 5/8", grade 80 hook. You can step up to grade 100 or 120 and stay with a smaller size, but youre getting into big bucks and not as much availabilty in the smaller sizes.

EDIT: some of this post is my opinon. The numbers are fact.

 

[opie74]

yup, if you take my M12000 for example, it is (obviously) rated at 12,000 lbs by Warn. Presumably one would expect that it would be capable of exerting a force of 12000 lbs on an object. Well, IIRC, the type of 3/8" line that it came with is standard rated at about 12,000 lbs breaking strength (*NOT* WLL). Which would imply that if you use the winch at its max rated capacity you are right on the edge of breaking your line. Not a comforting thought... Unless of course the 12,000 lbs winch cap is a pipe dream... Or their 3/8" line is a superduper one outside of normal ratings.
Clearly, many of these companies play loose with words in advertisement, counting on people's lack of knowledge to get away with it. Of course, nothing new there...
But throw in the fact that most people out there (and some here ) still don't understand that if you use a block, you can now exert 24000 lbs on what your block is attached to, and things can start to add up in a bad way quick...

Be safe out there!

Thats probably because you are only getting close to the 12,000 pounds pull on the first wrap of the drum. Each additional wrap on the drum decreases the maximum effective pull that can be generated by the winch.

That is weird they would put a line on the winch that has a breaking strength the same as the rating of the winch.

When you use a snatch block and run the line back to your rig, you are effectively splitting the load in half. Each leg of your line will carry half the weight of your rig, or split the ultimate load in half. Thats why you effectively double the pulling capacity.

For example, I just tested one of my products, and its single line average strength is 23,900. Tested in the configuration I built, it failed at 34,100. This is because its a loop, and the load was split in half and carried by 2 legs rather than 1.

 

[ForealBoreal]

I bought a fancy superwinch one. I like it a lot.
I am getting a warn one on my next truck (its coming with it)

I really like the ARB comp one but I am skeptical about a plastic roller.