Tow Ball Question

[NP99]

A mate of mine asked why you cant recover from a towball when its rated 3500kg and shackles are about the same! I couldn't answer him other than look at youtube for accidents...........more towball than any other.....and forums dont recommend it!

What is the answer?

[threedogs]

Because they kill, they are not designed for recovery , NEVER USE OR BE TEMPTED TO USE THEM
Plenty of rated recovery gear around

[TJsGQ]

Just take the tow ball out n use the pin inside it..!

[macca86]

They are a towing device a snatch recovery is a dynamic load and can shear the ball right off causing it to be a projectile. A shackle is a lifting device and should it fail will do so in a less spectacular way it will stretch and fail in small piece rather than a solid cannon ball

[NP99]

They are a towing device a snatch recovery is a dynamic load and can shear the ball right off causing it to be a projectile. A shackle is a lifting device and should it fail will do so in a less spectacular way it will stretch and fail in small piece rather than a solid cannon ball

Thats the sort of answer I need for him, thanks Macca

[threedogs]

Never ever use it to recovery< full stop
Dont take this the wrong way but is your mate an Idiot
This is a serious issue, PPL die from towball recoveries

[NP99]

Never ever use it to recovery< full stop
Dont take this the wrong way but is your mate an Idiot
This is a serious issue, PPL die from towball recoveries

If I cant push it out kinecticly with my bullbar, it stays stuck!

[Winnie]

Never ever use it to recovery&lt; full stop
Dont take this the wrong way but is your mate an Idiot
This is a serious issue, PPL die from towball recoveries

Bit harsh mate... I know it's an issue only because people aren't informed.

If you're happy and you know it tap a post!

[NP99]

Dont forget if you are new to this game, some things appear logical until they are explained!

[Maxhead]

Never ever use it to recovery< full stop
Dont take this the wrong way but is your mate an Idiot
This is a serious issue, PPL die from towball recoveries

I would rethink what your saying here TD!!!! or get OFF the meds!

[taslucas]

Never ever use it to recovery&lt; full stop
Dont take this the wrong way but is your mate an Idiot
This is a serious issue, PPL die from towball recoveries

Yeah just ease up a bit mate. You're not doing anyone any favours by calling people idiots.

FanTapstic!

[jack]

I'll own up, I wasn't aware of the danger till I joined the forum. Never been involved in a recovery before so never really thought about.

[NP99]

Never ever use it to recovery< full stop
Dont take this the wrong way but is your mate an Idiot
This is a serious issue, PPL die from towball recoveries

I know your idiot comment is not personal. He has a lot of recovery experience in one of these. It was just a question over coffee.

[growler2058]

I know your idiot comment is not personal. He has a lot of recovery experience in one of these. It was just a question over coffee.

Yeah i'd only callhim an idiot if i had 1 of these pointed at him hahahahhahahaha

[threedogs]

This is why every one should attend/join a club and do some proper Driver awareness and recovery course.
I have never looked at a towball and thought wow I'll get my mate out of that bog hole by looping the strap over
the ball. I joined a club. I also question so called experts when out bush on their practises too.Not putting his mate down don't know him
Nearly everyone here has a warning on their post there is page after page on the subject. yet still people ask is it ok. GMB
There are hard and fast rule when recovering a vehicle and towball is never mentioned. My club state this in the first line of introduction to 4x4ing
Think I'm harsh maybe . Tell me again when someone is injured

[NP99]

This is why every one should attend/join a club and do some proper Driver awareness and recovery course.
I have never looked at a towball and thought wow I'll get my mate out of that bog hole by looping the strap over
the ball. I joined a club. I also question so called experts when out bush on their practises too.Not putting his mate down don't know him
Nearly everyone here has a warning on their post there is page after page on the subject. yet still people ask is it ok. GMB
There are hard and fast rule when recovering a vehicle and towball is never mentioned. My club state this in the first line of introduction to 4x4ing
Think I'm harsh maybe . Tell me again when someone is injured

We joined the biggest 4WD club in Australia.........about 100,000 members.

[NissanGQ4.2]

Nearly everyone here has a warning on their post there is page after page on the subject. yet still people ask is it ok.

His mate know's not to recover from the towball the question in the first post is WHY cant you when its rated to tow

[nissannewby]

Never argue with an idiot cos from a distance no one can tell the difference.

Not implying anything here but someone's response was a little bit much. Take your time and read the original post.

[Biscuits]

Good on'ya Threedogs, I am in 100% agreement, you would have to be a deadset idiot to recover from the towball, even if you where unaware of the "cannonball" effect if it failed. I am pretty fresh into the 4wd world, and as a deadset green fella when I started 12 months ago, I was pretty aware that it wasn't too secure when I just popped the snatch over the ball... what it it fell off? what if the strap popped over the ball, what if...

Don't be an Idiot... don't recover from a towball...

[taslucas]

Yeah i'd only callhim an idiot if i had 1 of these pointed at him hahahahhahahaha

What, a chipmunk??

FanTapstic!

[NissanGQ4.2]

Good on'ya Threedogs, I am in 100% agreement, you would have to be a deadset idiot to recover from the towball, even if you where unaware of the "cannonball" effect if it failed. I am pretty fresh into the 4wd world, and as a deadset green fella when I started 12 months ago, I was pretty aware that it wasn't too secure when I just popped the snatch over the ball... what it it fell off? what if the strap popped over the ball, what if...

Don't be an Idiot... don't recover from a towball...

Well considering I let a mate hook a snatch over my towball for a recovery back in the days when I was new to the 4x4 scene I guess I'm just a dead set idiot. Still have the dent in my back door from when the snatch broke and went smashing into my door. Yep.......... could of been worse and I am very lucky it wasn't, did I learn from the mistake made yes, will I let let it happen again.....No F!ckin way

Well personally I don't think anyone is an idiot for recovering from the tow ball when not educated, hence the push with "WARNING: Towballs used for recoveries can, and do kill people and damage property." slogan

Dead set idiots are those that know the danger yet still do it

[threedogs]

Or Jeep drivers

[Biscuits]

His mate know's not to recover from the towball the question in the first post is WHY cant you when its rated to tow

The rating is not on the ball itself, it is on the entire towbar, bolts and the way it is bolted to the chassis/car. The ball itself, would probably still be made from mild steel, but maybe just a thicker shaft under the ball.

[NP99]

Or Jeep drivers

Mate, that's so funny with all the comments, he owns a jeep.....

[Maxhead]

The rating is not on the ball itself, it is on the entire towbar, bolts and the way it is bolted to the chassis/car. The ball itself, would probably still be made from mild steel, but maybe just a thicker shaft under the ball.

Hmm, ok.......I think the ball is rated to tow 3.5T
.27336






.........on the move

[threedogs]

Toyota Stamp their towballs 3500 kg what that translates to I dont know .
I would assume it means tow capacity, Still people will want to push the envelope.
"It didn't break last time so lets try again" wrong
Never seen a towball with Nissan logo , but I come from the dark side
I have an old style cast iron towball with a machined coach bolt for display only
That was in the days when you had 2 size towballs if any one remembers

[Clunk]

I also must be an idiot coz I didn't know about the whole tow ball thing either until I joined here just after buying the patrol.......... Not everyone is clued up on the different types of stresses that are involved in different materials in different applications.

It's all about educating people or re-education for some.

Oh and no, I have never done any sort of recovery using a towball.....


Don't stroke it, TAP it!!!!.....

[NP99]

Toyota Stamp their towballs 3500 kg what that translates to I dont know .
I would assume it means tow capacity, Still people will want to push the envelope.
"It didn't break last time so lets try again" wrong
Never seen a towball with Nissan logo , but I come from the dark side
I have an old style cast iron towball with a machined coach bolt for display only
That was in the days when you had 2 size towballs if any one remembers

Yep, and always had the wrong size when I borrowed a trailer!

[threedogs]

Heaps of ppl get confused as most recovery equipment is actually lifting gear
maybe my comment was right , tell him it was mean't as a throw away line.
I get my gear tested for towing via a NATA testing facility. You'll find things
like shackles and snatch blocks perfect if used correctly. There are many different ways to recover
but there is only one safe way, that hopefully should be Auswide is all recovery courses

[Maxhead]

Toyota Stamp their towballs 3500 kg what that translates to I dont know .
I would assume it means tow capacity, Still people will want to push the envelope.
"It didn't break last time so lets try again" wrong
Never seen a towball with Nissan logo , but I come from the dark side
I have an old style cast iron towball with a machined coach bolt for display only
That was in the days when you had 2 size towballs if any one remembers

Each towball must have 3 markings size, max tow capacity and batch number as per the Australian standards and ADR Rule

Tow Couplings – 50mm Ball Type Coupling Body Markings (up to 3500kg ATM)
Clause 12.4 of ADR 62 provides for three marking options for 50mm Coupling Bodies:
Option 1 Australian Standards “AS 4177-2004 Caravan and towing components”
Markings complying with AS 4177-2004 shall be legibly and permanently marked with
the following information (characters must be no less than 5mm in height):
a. ;
b. The mark „50‟ to indicate the size of towball for which it is intended;
c. Maximum rating in kilograms, e.g. 750kg, or 2000kg, or 3500kg;
d. A code to indicate serial number, batch, production date, or similar; and
e(i). The words „DO NOT WELD‟ if the coupling is manufactured from non-weldable
material; or
e(ii). The words 'WELD ONLY' if the coupling body is specifically designed to be
attached by welding only

[threedogs]

Then dont start on the plug, hey
I'll put pic of two piece ball here tomorrow.
Boy how things have changed

[NP99]

Hmm, ok.......I think the ball is rated to tow 3.5T
.27336






.........on the move
Those ark tow balls are going for $7 at super heap this week, bloody mark up from them shits me!

[NP99]

Genuine question deserves a genuine answer - Macca did that and no doubt others have additional "words" to add in a constructive way that will both provide more detail as to why (engineering, sheer weight vs lift vs pull) and strong emphasis on avoiding it at all costs EVEN if you don't understand why.

Getting emotional about it does no one any good ... we're here to learn - not sure if that changed at some stage, but that was my understanding ...

Don't think anyone went out of their way to offend, so let it slide and back to the topic.

DO NOT RECOVER UNDER ANY CIRCUMSTANCE FROM A TOWBALL.

Don't know the science, but I know how to heed the advice of others "older and wiser" than me, and if that doesn't seal it for you - type it into google, grab some popcorn and sit back and watch (and consider everyone of them lucky - as they are the ones who got away with it and thought it funny to post a video - the unlucky ones, of which there's many, are 6 feet under - and some of them were literally innocent bystanders).


Scotty (Bigrig)

Great Southern Camping
www.gscoffroad.com.au

Not to be a smart arse but google gives very little except the sad case in WA. YouTube however is full of the dingbats!

[mudnut]

Yeah, 3D, the old imperial towball was a smidgen smaller than the metric. Showing my middle age now, but my Grandad had a two piece tow ball on his early model cortina.

[MudRunnerTD]

So the Actual Question in the original Post was "Why cant we use a Towball? i need the information so i can Educate my friend" There was no challenge to our campaign, only support in sharing the knowledge gained here.

His friend takes it for granted like 80% of the population that the "Tow" Ball will work when "Towing" someone out with a Snatch strap! No Stupid people there! just Uneducated. The Very Intelligent and Trained and Educated Engineers at HOLDEN even shot a very expensive commercial to prove that the general public really dont get it!

So our forum is doing a World Service by sharing the knowledge as much as we can. If our friends are listening and newbys are seeing it all over our forum then our job is being done well.

His friend would only be an Idiot if once presented with the evidence and education gained from this thread and others threads on this forum he denied the logic and continued to use a Towball. At that point Punch him in the NECK!

As said in other posts, the Tow ball is rated to Pull a Load of up to 3.5ton as per the towing capacity of vehicle. It is not designed to be exposed to Sheer force created by a Kinetic Snatch strap and is in no way rated for this application.

Take the whole Tongue out and use the pin or buy a purpose made and rated recovery device.

Happy days, Stay Safe. Educate the Masses.

[growler2058]

Genuine question deserves a genuine answer - Macca did that and no doubt others have additional "words" to add in a constructive way that will both provide more detail as to why (engineering, sheer weight vs lift vs pull) and strong emphasis on avoiding it at all costs EVEN if you don't understand why.

Getting emotional about it does no one any good ... we're here to learn - not sure if that changed at some stage, but that was my understanding ...

Don't think anyone went out of their way to offend, so let it slide and back to the topic.

DO NOT RECOVER UNDER ANY CIRCUMSTANCE FROM A TOWBALL.

Don't know the science, but I know how to heed the advice of others "older and wiser" than me, and if that doesn't seal it for you - type it into google, grab some popcorn and sit back and watch (and consider everyone of them lucky - as they are the ones who got away with it and thought it funny to post a video - the unlucky ones, of which there's many, are 6 feet under - and some of them were literally innocent bystanders).


Scotty (Bigrig)

Great Southern Camping
www.gscoffroad.com.au

WoW WHAT a REPLY U sHOULD BE A MODERATOR

[twisty]

Got this info here (http://www.nissanpatrol.com.au/forums/showthread.php?6678-Nissan-Patrol-Magazine-November-Issue) (page 6). Condensed

My 4x4 usually weighs close to 3000kg (6600lb) on a trip. To move or pull a vehicle on a firm flat bitumen surface requires a force of about 10% of the loaded weight of the vehicle. Gravel or grass increases this to about 33%. The limit of a towballs capcity WITHOUT a snatch strap.

1lb equals 0.454kgs, or 1kg equals 2.2lbs.

Bogged
Bogged to the Base of the Wheel Rim, needs a pull of about 100% of the load.
Bogged to the wheel Hub, requires a pull of 200% of the load.
Bogged to the Belly or the Chassis, 300%.

Slope
• 15degree Slope = add +25% of the weight
• 30degree Slope = add +50%
• 45degree Slope = add +75%
For a Decline, or Downhill, change the "plus" to a "minus".

Example
I'm bogged to the Hubs on a 30 degree slope. (3000+50%)x2=9000kg (19800lb). Way beyond a towballs capacity

Share as you see fit.

[NP99]

Got this info here (http://www.nissanpatrol.com.au/forums/showthread.php?6678-Nissan-Patrol-Magazine-November-Issue) (page 6). Condensed

My 4x4 usually weighs close to 3000kg (6600lb) on a trip. To move or pull a vehicle on a firm flat bitumen surface requires a force of about 10% of the loaded weight of the vehicle. Gravel or grass increases this to about 33%. The limit of a towballs capcity WITHOUT a snatch strap.

1lb equals 0.454kgs, or 1kg equals 2.2lbs.

Bogged
Bogged to the Base of the Wheel Rim, needs a pull of about 100% of the load.
Bogged to the wheel Hub, requires a pull of 200% of the load.
Bogged to the Belly or the Chassis, 300%.

Slope
• 15degree Slope = add +25% of the weight
• 30degree Slope = add +50%
• 45degree Slope = add +75%
For a Decline, or Downhill, change the "plus" to a "minus".

Example
I'm bogged to the Hubs on a 30 degree slope. (3000+50%)x2=9000kg (19800lb). Way beyond a towballs capacity

Share as you see fit.

And a few drivers too!

[douglarv]

Toyota Stamp their towballs 3500 kg what that translates to I dont know .
I would assume it means tow capacity, Still people will want to push the envelope.
"It didn't break last time so lets try again" wrong
Never seen a towball with Nissan logo , but I come from the dark side
I have an old style cast iron towball with a machined coach bolt for display only
That was in the days when you had 2 size towballs if any one remembers

Do you not still have different sizes of tow balls? We just swapped one out of the receiver that was too big (2 inch vs. 1 1/2 inch) for the trailer hitch.

[cgm]

... why you cant recover from a towball when its rated 3500kg and shackles are about the same! ...

Having a valid answer for this or similar questions really bugged me for a long time. I reckon it is a fair question and even though you know you shouldn't, what are some "common sense" answers that let you go away feeling comfortable about why you shouldn't?

For me it started when being told at a club training day that I could not pull off the mount points on my ARB bar on my Rodeo. They looked like that's what they were made for!! The follow on was that it wasn't up for discussion or explanation, just that they're not made for it and that's it. Let me not go off topic, but just say that's where the similar thoughts started and it really bugged me that no one wanted to give me some reasonable technical or at least common sense technical level answer.

Coming back to the topic of the towball I think much of the issue is directly related to the quote on Growler's signature: "WARNING: TOWBALLS USED WITH SNATCHSTRAPS DO KILL!!"

I'm not saying the snatchstrap is the only problem with towball recoveries, but I think it is where the major issues start and most of the examples will be. I'm not a great fan of snatch straps simply because they can be so easily misused.

With an 8000kg snatch strap (the lighter rating size) it is difficult to tell how much force will actually be applied between the two vehicles. If the pulling truck is in low first and driven off slowly but constantly with the other truck lightly stuck and only 1-2 metres of slack, then the force won't be too much. But in real life the guy who is stuck is up to his bonnet in mud, has a heap of gear in the car (equal to lots of weight) and the bar of his car is nudged up against a hard edge coming out of the bog hole. In no time at all to have any chance of getting him out with a snatch strap it can escalate to a dangerous place. How much force is being put on now? These are the "youtube" ones where you see them run at top speed with 4 or 5 metres + of slack. All that energy goes into the stretched strap and it has to go somewhere. You can easily imagine now that the 8000kg strap is still going to stand up to much more than the 3500kg tow ball. You can also easily start to imagine that the force could be in excess of the 3500kg rating of the towball. Something has to give, hopefully the stuck vehicle, but otherwise it is going to be the next weakest link, which is probably the towball (or a poor recovery point).

This all ties in perfectly when you look at the forces required based on twisty's post, for the extra forces, etc.

To me this is a common sense starting point that lets me start to understand "why" we shouldn't do it.

There are some great background points in this ARB article (things like forces involved, not being able to control the use of a product, etc.):

http://www.arb.com.au/getting-started/ask-arb/recovery/Recovery_points.php
(I think this article was originally in the ARB Spring 2011 Newsletter as well, which is where I originally noticed it)

Coming back to the original question about the towball vs the shackle (quote from the article):


"Thankfully, there are standards for the shackles we all use to attach straps, however their rating system is based on lifting gear standards, and the safety factors in lifting gear mean that the rating is one fifth of the failure point."

So, going from this the common 4.75T (4750kg) shackle we usually see and use is not meant to break (as a safety factor) until it has 5 x 4.75 = 23.75T.

Do you think you'd have the same 5 x factor on the 3.5T towball? I really doubt it. Do you think you'd have the same 5 x factor on the 8000kg snatch strap? I'm sure it isn't. (there was a 4wd action article where they tested various brand staps until they broke, but I can't find it just now to see what rough factor it was - would love it if anyone had a reference to that?)

So, at least for me, that gives me a comfortable, "common sense" answer as to why not the towball when we use shackles in many situations with recoveries.

Final comment: Any solid object used in a recovery can easily end up being a deadly "missile" - including shackles. Minimize their use, never join straps with them and always hook to a solid rated recovery point (rated points is a whole other topic, but I'll leave that to TD and other experts). You can use a good shackle on a good strap and hook it to a tie down point which will break and easily still kill someone with no towball involved.

Sorry for the long answer, but hope some of this makes sense to answer the actual question.

[NP99]

Having a valid answer for this or similar questions really bugged me for a long time. I reckon it is a fair question and even though you know you shouldn't, what are some "common sense" answers that let you go away feeling comfortable about why you shouldn't?

For me it started when being told at a club training day that I could not pull off the mount points on my ARB bar on my Rodeo. They looked like that's what they were made for!! The follow on was that it wasn't up for discussion or explanation, just that they're not made for it and that's it. Let me not go off topic, but just say that's where the similar thoughts started and it really bugged me that no one wanted to give me some reasonable technical or at least common sense technical level answer.

Coming back to the topic of the towball I think much of the issue is directly related to the quote on Growler's signature: "WARNING: TOWBALLS USED WITH SNATCHSTRAPS DO KILL!!"

I'm not saying the snatchstrap is the only problem with towball recoveries, but I think it is where the major issues start and most of the examples will be. I'm not a great fan of snatch straps simply because they can be so easily misused.

With an 8000kg snatch strap (the lighter rating size) it is difficult to tell how much force will actually be applied between the two vehicles. If the pulling truck is in low first and driven off slowly but constantly with the other truck lightly stuck and only 1-2 metres of slack, then the force won't be too much. But in real life the guy who is stuck is up to his bonnet in mud, has a heap of gear in the car (equal to lots of weight) and the bar of his car is nudged up against a hard edge coming out of the bog hole. In no time at all to have any chance of getting him out with a snatch strap it can escalate to a dangerous place. How much force is being put on now? These are the "youtube" ones where you see them run at top speed with 4 or 5 metres + of slack. All that energy goes into the stretched strap and it has to go somewhere. You can easily imagine now that the 8000kg strap is still going to stand up to much more than the 3500kg tow ball. You can also easily start to imagine that the force could be in excess of the 3500kg rating of the towball. Something has to give, hopefully the stuck vehicle, but otherwise it is going to be the next weakest link, which is probably the towball (or a poor recovery point).

This all ties in perfectly when you look at the forces required based on twisty's post, for the extra forces, etc.

To me this is a common sense starting point that lets me start to understand "why" we shouldn't do it.

There are some great background points in this ARB article (things like forces involved, not being able to control the use of a product, etc.):

http://www.arb.com.au/getting-started/ask-arb/recovery/Recovery_points.php
(I think this article was originally in the ARB Spring 2011 Newsletter as well, which is where I originally noticed it)

Coming back to the original question about the towball vs the shackle (quote from the article):


"Thankfully, there are standards for the shackles we all use to attach straps, however their rating system is based on lifting gear standards, and the safety factors in lifting gear mean that the rating is one fifth of the failure point."

So, going from this the common 4.75T (4750kg) shackle we usually see and use is not meant to break (as a safety factor) until it has 5 x 4.75 = 23.75T.

Do you think you'd have the same 5 x factor on the 3.5T towball? I really doubt it. Do you think you'd have the same 5 x factor on the 8000kg snatch strap? I'm sure it isn't. (there was a 4wd action article where they tested various brand staps until they broke, but I can't find it just now to see what rough factor it was - would love it if anyone had a reference to that?)

So, at least for me, that gives me a comfortable, "common sense" answer as to why not the towball when we use shackles in many situations with recoveries.

Final comment: Any solid object used in a recovery can easily end up being a deadly "missile" - including shackles. Minimize their use, never join straps with them and always hook to a solid rated recovery point (rated points is a whole other topic, but I'll leave that to TD and other experts). You can use a good shackle on a good strap and hook it to a tie down point which will break and easily still kill someone with no towball involved.

Sorry for the long answer, but hope some of this makes sense to answer the actual question.

I appreciate your reply mate, thank you. Sometimes when you get a response of because it is so, or like you mentioned there will be no debate on this, you start to doubt the validity of a statement.

[rottodiver]

Shackles have a safety factor of 6... Eg a 4.25 shackle will fail at 25.5 T
This is the reason shackles are for lifting and pulling!!!!!!
Scotty

[lhurley]

Got this info here (http://www.nissanpatrol.com.au/forums/showthread.php?6678-Nissan-Patrol-Magazine-November-Issue) (page 6). Condensed

My 4x4 usually weighs close to 3000kg (6600lb) on a trip. To move or pull a vehicle on a firm flat bitumen surface requires a force of about 10% of the loaded weight of the vehicle. Gravel or grass increases this to about 33%. The limit of a towballs capcity WITHOUT a snatch strap.

1lb equals 0.454kgs, or 1kg equals 2.2lbs.

Bogged
Bogged to the Base of the Wheel Rim, needs a pull of about 100% of the load.
Bogged to the wheel Hub, requires a pull of 200% of the load.
Bogged to the Belly or the Chassis, 300%.

Slope
• 15degree Slope = add +25% of the weight
• 30degree Slope = add +50%
• 45degree Slope = add +75%
For a Decline, or Downhill, change the "plus" to a "minus".

Example
I'm bogged to the Hubs on a 30 degree slope. (3000+50%)x2=9000kg (19800lb). Way beyond a towballs capacity

Share as you see fit.

Great info, rather interesting too.

Reading this got me thinking, Using twisty's example, the force required to move the car was 9000kg, now this isnt an uncommon situation to be in.

How can a 12000lb winch move the car? 12000lb is only 5448kg. Is there something Im missing that makes the winch be able to pull TWICE its capacity?

[macca86]

Winch blocks double and triple line pulls

[healy]

Got this info here (http://www.nissanpatrol.com.au/forums/showthread.php?6678-Nissan-Patrol-Magazine-November-Issue) (page 6). Condensed

My 4x4 usually weighs close to 3000kg (6600lb) on a trip. To move or pull a vehicle on a firm flat bitumen surface requires a force of about 10% of the loaded weight of the vehicle. Gravel or grass increases this to about 33%. The limit of a towballs capcity WITHOUT a snatch strap.

1lb equals 0.454kgs, or 1kg equals 2.2lbs.

Bogged
Bogged to the Base of the Wheel Rim, needs a pull of about 100% of the load.
Bogged to the wheel Hub, requires a pull of 200% of the load.
Bogged to the Belly or the Chassis, 300%.

Slope
• 15degree Slope = add +25% of the weight
• 30degree Slope = add +50%
• 45degree Slope = add +75%
For a Decline, or Downhill, change the "plus" to a "minus".

Example
I'm bogged to the Hubs on a 30 degree slope. (3000+50%)x2=9000kg (19800lb). Way beyond a towballs capacity

Share as you see fit.
I'm gonna disagree with this what about a winch? How does that pull the car in some of those situations. The only time I use a towball is for the trailer other than that it won't be on the car ok same question asked

[lhurley]

Winch blocks double and triple line pulls

Ok yes, i didnt think of that. Is a double line pull a common thing?? or are more people inclined to just line it up and go a single line?

[NP99]

Ok yes, i didnt think of that. Is a double line pull a common thing?? or are more people inclined to just line it up and go a single line?

Depends how much you need to pull.

[MudRunnerTD]

Got this info here (http://www.nissanpatrol.com.au/forums/showthread.php?6678-Nissan-Patrol-Magazine-November-Issue) (page 6). Condensed

My 4x4 usually weighs close to 3000kg (6600lb) on a trip. To move or pull a vehicle on a firm flat bitumen surface requires a force of about 10% of the loaded weight of the vehicle. Gravel or grass increases this to about 33%. The limit of a towballs capcity WITHOUT a snatch strap.

1lb equals 0.454kgs, or 1kg equals 2.2lbs.

Bogged
Bogged to the Base of the Wheel Rim, needs a pull of about 100% of the load.
Bogged to the wheel Hub, requires a pull of 200% of the load.
Bogged to the Belly or the Chassis, 300%.

Slope
• 15degree Slope = add +25% of the weight
• 30degree Slope = add +50%
• 45degree Slope = add +75%
For a Decline, or Downhill, change the "plus" to a "minus".

Example
I'm bogged to the Hubs on a 30 degree slope. (3000+50%)x2=9000kg (19800lb). Way beyond a towballs capacity

Share as you see fit.


So the above Info was actually used by AB in the November Mag of the forum but he found it in this thread i produced in the early days on this forum

Recovery-The-Fundamentals (http://www.nissanpatrol.com.au/forums/showthread.php?1984-Recovery-The-Fundamentals)

Having a good read of the first few posts are a timely reminder and a good education for our group and pertinent to this thread.



Great info, rather interesting too.

Reading this got me thinking, Using twisty's example, the force required to move the car was 9000kg, now this isnt an uncommon situation to be in.

How can a 12000lb winch move the car? 12000lb is only 5448kg. Is there something Im missing that makes the winch be able to pull TWICE its capacity?


Given that it was an extract have a look at that thread and scroll down to the section regarding the Snatch Block. In fact start from the top and it will all become clear and make sense. The Power of the Snatch Block!!



Winch blocks double and triple line pulls

^^^What He Said^^^



I'm gonna disagree with this what about a winch? How does that pull the car in some of those situations.


Healy have a read mate. Recovery-The-Fundamentals (http://www.nissanpatrol.com.au/forums/showthread.php?1984-Recovery-The-Fundamentals)



Ok yes, i didnt think of that. Is a double line pull a common thing?? or are more people inclined to just line it up and go a single line?

I use them all the time. dont wait until your winch stalls and you burn the motor out! if in doubt use a snatch block.


Depends how much you need to pull.

^^^What he said^^^ ;)

[lorrieandjas]

Guys - the thing to remember here is it is all about physics - but more importantly about safety! On some recoveries we are talking about massive amounts of force in the equation. Without going into details - if you have a piece of your recovery platform let go at say 12,000kg, the resultant movement of any projectile in the recovery is about 40 metres per second dependent on mass (using a lot of assumptions here!). Think about it - that tow ball or unrated recovery point is going to punch you in the neck pretty quick! It doesn't ever, ever, ever need to get to that.

One thing I will comment on that has been said by MR and others but seems lost in the double line or triple line pull excitement - remember that while the snatch block reduces effort on the winch - the forces on the anchor points are still the sum of the recovery effort. So you better hope you have a good recovery point and that those trees are well anchored in by their roots! Wise advice given to me - if in doubt - don't do it! But if you know what you are doing a tough recovery is thing of beauty!

Jas