Post by: Symon on June 16, 2017, 08:07:47 AM
http://www.brisbanetimes.com.au/queensland/man-killed-by-snapped-strap-while-trying-to-tow-mate-on-beach-20170615-gws7am.html (http://www.brisbanetimes.com.au/queensland/man-killed-by-snapped-strap-while-trying-to-tow-mate-on-beach-20170615-gws7am.html)
Post by: duggie on June 16, 2017, 08:33:41 AM
Post by: Patr80l on June 16, 2017, 09:02:35 AM
Lesson for novices: a chain is not a snatch strap.
https://www.facebook.com/EmsTheFunnySide/posts/1384171765001456 (https://www.facebook.com/EmsTheFunnySide/posts/1384171765001456)
Post by: GBC on June 16, 2017, 09:16:38 AM
This one did not end well.
Lesson for novices: a chain is not a snatch strap.
https://www.facebook.com/EmsTheFunnySide/posts/1384171765001456 (https://www.facebook.com/EmsTheFunnySide/posts/1384171765001456)
Have a close look. It is a strap loop connection into the back of the ute and it is a strap for the main part. Either they have spliced in a metre section of chain which I cannot imagine would happen (but is possible), or is the section that looks like chain actually the splicing (woven) section of the strap? Overseas they have round kinetic straps that you weave back on themselves to make the connection.
In any event, I am sad for the young bloke. We lost a young bloke in Hervey Bay a few years back who was well known around town.
Post by: MattNQ on June 16, 2017, 10:12:32 AM
Gets me wondering - at our workplace, our riggers and dogmen require training and tickets to move heavy loads around using winches, straps and shackles.
Unfortunately anyone can buy a strap, chain, shackles etc and try to move their 3tonnes of bogged fourby.
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Post by: Bird on June 16, 2017, 10:30:15 AM
Quote from: Patr80l
This one did not end well.not really sure why the OP would post a vid of some dude getting killed.. then again that's faceplant for ya which makes no sense to me either...
Lesson for novices: a chain is not a snatch strap.
https://www.facebook.com/EmsTheFunnySide/posts/1384171765001456 (https://www.facebook.com/EmsTheFunnySide/posts/1384171765001456)
Post by: duggie on June 16, 2017, 10:47:49 AM
not really sure why the OP would post a vid of some dude getting killed.. then again that's faceplant for ya which makes no sense to me either...
I was reading through some of the comments from this , and it was mentioned the the driver of the vehicle walked out unharmed , the vid that we saw was an edited version and evidently there is a longer version of the attempted recovery .
Post by: Troopy_03 on June 16, 2017, 11:08:32 AM
While the chain possibly/probably recoils less than a snatch strap or cable, the weight of the chain hitting something at any speed would do a lot of damage. Connecting a chain to a snatch strap is a bit like tying a sinker to a rubber band and stretching it. A recipe for disaster.
Post by: Rodt on June 16, 2017, 12:02:43 PM
None of this is taught in plant training unfortunately unless the trainer understands the issues as the expectation is always that you don't overstress chains or even don't use them unless absolutely necessary. They also don't like sudden massive stresses also even if well within supposed weight limits
Very sad incident
Post by: Rumpig on June 16, 2017, 04:15:19 PM
https://m.youtube.com/watch?v=oISdDPliZSA
Post by: Bird on June 16, 2017, 04:21:37 PM
Determine Speed of Shackle if Snatch Strap Breaks.
If all the Elastic Energy of the Snatch Strap is transferred to Kinetic Energy in the Shackle then the peak Speed of the Shackle as the Snatch Strap returns to it's 9.0m length can be determined. (Assuming no losses due to friction)
From Energy Conservation,
Elastic Energy in Snatch Strap = Kinetic Energy of Shackle
PEStrap = KEShackle
1/2 k x2 = 1/2 m v2
where k = spring constant
x = distance stretched (meters)
m = mass of shackle (kg)
v = velocity of shackle (m/s)
1/2 (20750N/m) (0.579m)2 = 1/2 (0.68kg) v2
v = 101m/s
or Peak Speed of Shackle v = 364 km/h
Post by: glenm64 on June 16, 2017, 04:27:34 PM
http://www.whyalla4wd.org.au/Shackles.html (http://www.whyalla4wd.org.au/Shackles.html)
Determine Speed of Shackle if Snatch Strap Breaks.
If all the Elastic Energy of the Snatch Strap is transferred to Kinetic Energy in the Shackle then the peak Speed of the Shackle as the Snatch Strap returns to it's 9.0m length can be determined. (Assuming no losses due to friction)
From Energy Conservation,
Elastic Energy in Snatch Strap = Kinetic Energy of Shackle
PEStrap = KEShackle
1/2 k x2 = 1/2 m v2
where k = spring constant
x = distance stretched (meters)
m = mass of shackle (kg)
v = velocity of shackle (m/s)
1/2 (20750N/m) (0.579m)2 = 1/2 (0.68kg) v2
v = 101m/s
or Peak Speed of Shackle v = 364 km/h
Should have left the link off and impressed us with your mathmatic skills.
I get a headache nowadays with any number over 10.
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Post by: Bird on June 16, 2017, 04:32:28 PM
Should have left the link off and impressed us with your mathmatic skills.
I get a headache nowadays with any number over 10.
These days I'm as bad as the kid at the Chinese last night who couldn't work out in his head the change from a $10 note for $8.40 of noodle box.
Post by: Traveller on June 16, 2017, 04:35:16 PM
I get a headache nowadays with any number over 10.
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x2
Post by: Troopy_03 on June 16, 2017, 04:37:01 PM
These days I'm as bad as the kid at the Chinese last night who couldn't work out in his head the change from a $10 note for $8.40 of noodle box.None, it's called a tip ;D
Post by: Bird on June 16, 2017, 04:51:58 PM
Quote from: Troopy_03
None, it's called a tip ;DWhat Shitted me most was the owners attitude to the kid who was tryin to use the calculator on the counter (I didn't mind) and then the owner said "its his first day"...
I replied 'everyone started somewhere... give the kid a break ya arrogant prick, the joints flat out and hes doin his best and I'm in no rush...'
he didn't like that... probably spat in my noodles.
Post by: BaseCamp on June 16, 2017, 05:35:19 PM
What Shitted me most was.... he probably spat in my noodles.
Talk about lucky then. ... ya dinner had some flavour then? .....
as well as texture -- (being served in its own box)...
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Post by: The punter on June 16, 2017, 05:58:29 PM
Probably a good time to remind people of how to safely use a snatch strap....they aren't designed to be used with big run ups, if you need a big run up to extricate the vehicle, then you either haven't done the right prep work for a safe recovery or are using the wrong recovery item for that recovery. I bogged this vehicle to the axles for this video, you don't see it in the video but the vehicle recovering it stalled when the snatch strap pulled tight, and it was still enough energy in the strap to unbog my Cruiser.
https://m.youtube.com/watch?v=oISdDPliZSA
Great video, should be mandatory viewing on DVD with every strap purchase.
Post by: Rumpig on June 16, 2017, 06:57:37 PM
Great video, should be mandatory viewing on DVD with every strap purchase.:cheers: it was made for a Fraser Island Fishing Expo quite a few years ago, filmed by WIN TV and unfortunately with the event being solely sponsored by Toyota we weren't allowed to show the non Toyota vehicle owned by the guy in the video doing the recovering...it would have been nice to show the recovering vehicle stalling, just to show speed is not required to make a snatch strap work how it's designed to do
Post by: Squalo on June 17, 2017, 08:54:58 AM
Not many details, but a good reminder to be careful.
http://www.brisbanetimes.com.au/queensland/man-killed-by-snapped-strap-while-trying-to-tow-mate-on-beach-20170615-gws7am.html (http://www.brisbanetimes.com.au/queensland/man-killed-by-snapped-strap-while-trying-to-tow-mate-on-beach-20170615-gws7am.html)
Even if the details were spelled out to the media organisation(s) they will still report it in words and terms that they themselves can understand. No, it's not a 'freak towing accident'; that's when a propeller falls off a plane flying overhead and severs the snatch strap during a recovery.
Someone simply (and sadly) didn't follow correct safety procedures. Sounds to me like a shackle might have been attached to a tie-down point on the bogged vehicle... a flying strap alone won't kill a driver especially if it's already disipated most of its kinetic energy by breaking a window.
Condolences to family and friends of all involved :(
Post by: prodigyrf on June 17, 2017, 12:41:28 PM
(I used to worry the life out of my teachers not sticking to the curriculum too)
Post by: Bird on June 17, 2017, 02:01:31 PM
So what does it say about winches with big heavy hooks on them and the strap around the tree breaks? Sounds to me like they should only have a strap loop on the end of them?you don't use a winch blanket?
Post by: shanegtr on June 17, 2017, 06:35:05 PM
Post by: Squalo on June 17, 2017, 10:50:30 PM
So what does it say about winches with big heavy hooks on them and the strap around the tree breaks? Sounds to me like they should only have a strap loop on the end of them?
(I used to worry the life out of my teachers not sticking to the curriculum too)
As Bird said, that's what winch blankets are for, but rope is not nearly as dangerous as steel winch cables. I've personally sat in a vehicle hanging on a rope when the winch has stalled, bonnet raised and ducked behind the dash to be sure, as the rope was cut with a hacksaw (and you can bet the mate cutting it was nervous but he cut it at the hook so it was only going to go away from him) - and the rope simply drops to the ground, no recoil.
Latest on this says "Initial investigations suggest a tow point on the bull bar of the car being towed broke, causing the towing strap to fly through the back window of Mr Poulsen's car and hit him."
http://www.brisbanetimes.com.au/queensland/tributes-for-man-who-died-trying-to-help-a-mate-on-central-queensland-beach-20170616-gwt1so.html (http://www.brisbanetimes.com.au/queensland/tributes-for-man-who-died-trying-to-help-a-mate-on-central-queensland-beach-20170616-gwt1so.html)
You see tow points welded or bolted to bullbars, I always wonder about them. Recovery point bolted to the chassis, independent of the bullbar, is the only thing I trust.
Post by: prodigyrf on June 17, 2017, 11:26:20 PM
Latest on this says "Initial investigations suggest a tow point on the bull bar of the car being towed broke, causing the towing strap to fly through the back window of Mr Poulsen's car and hit him."You'd reckon it had to be a single cab ute and something heavy attached to that strap but what about the seat headrest or did he have one hand on the wheel and head cocked around in the middle looking out the back window and all the planets had aligned. That's like the 15yr old lass at my son's old school walking the dog and tripped over the lead and hit her head on the corner of the kerb and gone.
That's the sort of stuff that made Ripleys before the internet age - https://en.wikipedia.org/wiki/Ripley%27s_Believe_It_or_Not%21
Post by: oldmate on June 18, 2017, 01:55:56 PM
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Post by: Bird on June 19, 2017, 11:08:33 AM
Quote from: oldmate
I just don't understand why you don't use dampeners on anything. Winch or snatch. Doesn't matter one should be used. And I know there is some old blokes on here that will give me the old " I've been dragging trucks out of bogs for years and never needed one". Wake up people. This type of Shit happens and happens quick. If it doesn't seem right, don't so it. People die!!
x williontybillionovich
Post by: Troopy_03 on June 19, 2017, 01:00:21 PM
I just don't understand why you don't use dampeners on anything. Winch or snatch. Doesn't matter one should be used. And I know there is some old blokes on here that will give me the old " I've been dragging trucks out of bogs for years and never needed one". Wake up people. This type of Shit happens and happens quick. If it doesn't seem right, don't so it. People die!!
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And plenty of young blokes who just seem to think it wouldn't/couldn't happen to them.
Post by: oldmate on June 19, 2017, 02:22:46 PM
And plenty of young blokes who just seem to think it wouldn't/couldn't happen to them.
yeah dead right mate. it only take .0875478 of a sec and its all over.
ps, do not quote me on the time, i didnt google it first, just guessed
Post by: Squalo on June 21, 2017, 08:46:39 AM
ps, do not quote me on the time, i didnt google it first, just guessed
Straight out of Bird's Book Of Guesstimating :)
Here's one of the biggest problems with these avoidable tragedies. The media has to purposely be vague about exactly what went wrong, because fatalities require official investigations, but the results of those aren't available for some time - at which point everyone except family has forgotten about it.
So no-one in the greater public learns anything, and it happens again, and again.
Post by: Beachman on June 21, 2017, 11:58:55 AM
If it doesn't seem right, don't so it. People die!!
So true. A couple of years ago I did a day trip to Bribie and for the people who know Bribie when the lagoons were flowing they become shallow at low tide, so this young goose decides to drive into the lagoon to do circle work.
What he didn’t count on was the sand base was thin and then ankle deep mud below. So like expected he went down to the chassis.
It didn’t take long to get a large crowd watching/filming his mate with 3 x snatch strap joined with a shackles and then using each other’s towballs with his mate going as fast as he could trying to pull him out. Some of the crowd (including kids) were standing way too close for comfort.
A couple of guys from the crowd went over and gave them some advice on how dangerous what they were doing, but they basically laughed at them. This is when myself and another couple of Dad’s walked our families away as didn’t want to be around (especially with kids) if it went bad.
Luckily nothing happened, but it was a recipe for disaster.
Post by: The punter on June 21, 2017, 12:10:46 PM
Post by: Pete79 on June 21, 2017, 01:12:08 PM
And all they had to do was the magazine thing to join the straps and use the hitch pin - safety factor increased tenfold for zero cost and 5 minsAhh, it's finally become clear.
For years I've been trying to figure why the hell they keep producing all of those rubbish 4wd magazines.
And there it is... They only exist to join snatch straps together.
But then that raises another question, how many recoveries are people doing that they need annual subscriptions for those things?
Surely a driver training course would be a better investment?
Post by: The punter on June 21, 2017, 02:16:14 PM
Ahh, it's finally become clear.
For years I've been trying to figure why the hell they keep producing all of those rubbish 4wd magazines.
And there it is... They only exist to join snatch straps together.
But then that raises another question, how many recoveries are people doing that they need annual subscriptions for those things?
Surely a driver training course would be a better investment?
You mean those books full of ads people pay for? 8)
Post by: austastar on June 21, 2017, 02:59:56 PM
With no mag, you can afford more stuff.
Ironic - somewhat.
Cheers
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Post by: briann532 on June 21, 2017, 03:21:20 PM
yeah dead right mate. it only take .0875478 of a sec and its all over.
ps, do not quote me on the time, i didnt google it first, just guessed
It's ok mate, I'm 113% sure that you're dead accurate............
Post by: oldmate on June 21, 2017, 03:43:17 PM
And all they had to do was the magazine thing to join the straps and use the hitch pin - safety factor increased tenfold for zero cost and 5 minsTrue true. You would be surprised at the amount of 4wd owners who don't know how too join straps. 2015 cape trip. Nolans brook. I had to teach a group of 4 cars lol decked out with all the kit how to do it. They had NFI
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Post by: NewieCamper on June 22, 2017, 03:31:02 PM
Straight out of Bird's Book Of Guesstimating :)But it wouldn't be to hard to add a line in the story to say: Investigations are ongoing into the exact cause, but don't forget to use a dampener folks it can prevent a shackle becoming a missile in case something breaks.
Here's one of the biggest problems with these avoidable tragedies. The media has to purposely be vague about exactly what went wrong, because fatalities require official investigations, but the results of those aren't available for some time - at which point everyone except family has forgotten about it.
So no-one in the greater public learns anything, and it happens again, and again.
Post by: prodigyrf on June 22, 2017, 05:04:08 PM
Post by: DrewXT on June 22, 2017, 07:13:16 PM
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Post by: austastar on June 22, 2017, 07:40:09 PM
And how many legally own firearms I wonder to myself!
Darwin failed that one - this time.
Cheers
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Post by: prodigyrf on June 23, 2017, 01:20:25 AM
Post by: muzza01 on June 23, 2017, 05:18:35 AM
True true. You would be surprised at the amount of 4wd owners who don't know how too join straps. 2015 cape trip. Nolans brook. I had to teach a group of 4 cars lol decked out with all the kit how to do it. They had NFI
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You would be surprised how many people have no idea how to actually engage 4wd on their vehicle, lock the hubs in if fitted or even jack up their car and change a wheel.
Stupid people are everywhere these days
Post by: Fathom on June 23, 2017, 07:37:00 AM
I was just talking to a work colleague the other day who was adamant his factory tie down points were acceptable for recoveries. The salesman told him.. his mechanic told him. So I must be wrong..
He kept asking when he can come to the Glasshouse 4wding with us.. I kept telling him he can't.
After this convo happening about 590 times I ended up giving him a real spray..
Which I normally try not to do.
I try.. to tell people that stuff once.. if they don't listen. Not my problem. I'm not 4wding with them. It's their and their family's problem.
Then I looked back over all the years I have owned a 4B.
Which is since I was about 19 or 20.
Up to about 15 Years ago I was recovering off the tow ball. Didn't know any better.
No 4wd club to tell me, no forums, was more into street cars so didn't buy mags.
Didn't go to 4wd accessory shops. Etc.
Even when I was first told, I was dumbstruck that a thinner bit of metal (rated shackle) would be stronger/safer than a thicker tow ball)
I knew jack squat about steel/application force etc.
I have seen videos 10ish years ago of 'Magazine/TV 4wd gurus'. Hooking a snatch to the front of a winch hook promoting it as a safe recovery method. (Winch rope on drum- just using it as a connection point.
Not too many years ago, with the rise of the dual cab utes. And IFS. The major 4wd accessory shops took a bit to catch up and didn't have an answer for front recovery points. I have heard salespeople there saying just use a bridle strap and you'll be right..
Once whenever anyone was stuck I would stop and recover them. Now I want to know, do they have rated recovery points/ their own gear/ their tyre pressures. etc.
And when I don't help. They probably think I'm an Ahole. While I'm thinking .. if you don't pay.. (for the right gear) don't play.
I guess. What I'm saying is it's even now still hard to get info for some people.
We all learn. Someone had to tell us.
Hopefully we find better ways to educated Joe Average.
Post by: Merts on June 23, 2017, 08:20:37 AM
Post by: Ben.Archer on June 23, 2017, 08:24:24 AM
Post by: oldmate on June 23, 2017, 09:42:03 AM
It's worth noting that factory tow points and factory tie down points are completely different things. Some tow points (such as the ones on my MQ Triton) are suitable for recoveries. Tie down points certainly are not.
Yes, the ones on my disco front and rear are transport tie down points but also rated for recoveries.
So they are bolted to your chassis with HT bolts and stamped with load rating?
Post by: Fathom on June 23, 2017, 10:01:44 AM
It's worth noting that factory tow points and factory tie down points are completely different things. Some tow points (such as the ones on my MQ Triton) are suitable for recoveries. Tie down points certainly are not.
Yes, the ones on my disco front and rear are transport tie down points but also rated for recoveries.
Agree they are separate things however
They are not rated recovery points.
Tie down points are tie down points. Transit.
Tow points are good for a flat tow say on bitumen . or winching onto a tow truck.
They are not suitable for snatch recoveries.
Or the force of a vehicle stuck in mud, suction etc.
(Edit to try and help... ) for instance I can push my 2t 4wd on road. Even up a slight incline. Five blokes can't move me stuck deep in sand or mud.
Much different force required.
Nature may not allow a straight line pull etc..
As Oldmate said
Not rated at all- there won't be a rating stamp on them.
Incidentally I have seen a Disco's front tow point fly through (yes I mean through) an aluminium bullbar and land still attached to the snatch strap past the recovery vehicle.
I wouldn't have considered it an overly excessive snatch.
Again. Not my problem if you disagree. Just letting you know.
(Edit) For a couple of hundred bucks. Even if you think I'm only half right.. why take the chance with your life and your family and friends.
Post by: Beachman on June 23, 2017, 11:29:56 AM
Majority of my 4WDing is with friends, so odds are they would be recovering me if ever needed. My take is for $200 it reduces my chances of having a tough conversation with a friend’s family.
Post by: Bird on June 23, 2017, 12:28:51 PM
One of the first modifications I did to my 2nd cruiser was change the tie down points (Which everyone said were fine) to rated points with HT bolts.
That brings on another point.. there were issues a while ago with some 3rd party companies that were fitting bullbars etc without HT bolts.. worth checking.
Post by: rags on June 23, 2017, 08:07:58 PM
Post by: prodigyrf on June 23, 2017, 10:16:51 PM
Then I looked back over all the years I have owned a 4B.
Which is since I was about 19 or 20.
We all learn. Someone had to tell us.
Listen, learn...tow points! Who needs rated tow points? All you need is lots of input and enthusiasm at that age- https://www.youtube.com/watch?v=HJA3J--g_yI (https://www.youtube.com/watch?v=HJA3J--g_yI)
plus plenty of beer to lubricate proceedings naturally :cheers:
You probably have to get a missus, kids and a mortgage to do the wiser old fart homework scene- https://www.youtube.com/watch?v=oT6R6yTg6R0 (https://www.youtube.com/watch?v=oT6R6yTg6R0)
although the close shaves and dramas as a young bloke sorts out the gene pool :angel:
Post by: Cruiser 105Tvan on June 24, 2017, 12:58:36 AM
Post by: Merts on June 24, 2017, 10:14:33 PM
Post by: prodigyrf on June 24, 2017, 11:44:39 PM
Post by: oldmate on June 25, 2017, 08:10:38 AM
Whether a tow point has a rating stamped on it, or if it's bolted to the chassis (or welded to it) doesn't determine whether its structurally suitable for a snatch recovery. I'm extremely confident my snatch strap will fail well before the tow points do.
How do you know what it's rated for? Big difference between something being bolted and welded. Bit clearly you are one of the blokes I mentioned earlier.
Hope you are right. I wouldnt recover you.
Call me an asshole but the safety and lives of others and myself is more than saving your car from the drink.
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Post by: Pete79 on June 25, 2017, 08:37:47 AM
All this stamped 'rated' stuff means absolutely zero.
You can buy a hook with a number stamped on it and bolt it to any chassis with M12 high tensile bolts and it means nothing as far as ratings go.
As a boilermaker I can grab a 50 ton lifting lug and weld to to a steel plate with a 3 run fillet weld and stamp it with my numbers, but it means nothing if that plate is 1.5mm thick and only tack welded to the rest of the load.
As far as I know there are no 'rated' recovery points fitted on any vehicles, plenty of meaningless numbers stamped on things though....
Post by: Merts on June 25, 2017, 08:46:09 AM
How do you know what it's rated for? Big difference between something being bolted and welded. Bit clearly you are one of the blokes I mentioned earlier.
Hope you are right. I wouldnt recover you.
Call me an asshole but the safety and lives of others and myself is more than saving your car from the drink.
I'm a civil engineer as a matter of fact, so I may have more knowledge on the strength of steel components and fastening systems than you assume I do.
My point was that a recovery/tow point does not have to be bolted on, or to have been destruction tested in order to be suitable for using in a snatch recovery. You are correct that welding and bolting are different, but your apparent belief that one is superior to the other is simply wrong. Both methods are used in construction and either can provide the required strength.
I agree which your point, that in the absence of testing, I can't be sure of the exact failure capacity of the factory tow points. What I have done however is measured those points and compared them to after market rated points. I'm confident, particularly if an equalising bridle is used, they are adequate for a snatch recovery. I would always use a dampener (or two) on the strap btw.
Also, what Pete just said....
Post by: Chris. on June 25, 2017, 08:59:24 AM
Here's a MMAL video of them testing the snatching from the OEM recovery points: https://www.youtube.com/watch?v=wPXixsvjDjY&index=2&list=WL (https://www.youtube.com/watch?v=wPXixsvjDjY&index=2&list=WL)
Post by: rags on June 25, 2017, 09:15:10 AM
Can anyone point to any vehicles with factory fitted "rated" recovery points?
All this stamped 'rated' stuff means absolutely zero.
And just because a snatch strap comes in packaging that claims to be rated to xxx kg and xxx technical standard can mean nothing. Manufacturers can and will copy anything to claim that the product is safe with little quarantine over those claims. In fact it was not long ago that 2 of Australia's largest three letter named companies were forced into a product recall.
In a previous job I witnessed camper trailer importers having hitches fitted that were in fact fraudulent copies, proporting to be brand x, but in fact untested copies.
I have fitted to my ARB bullbar some recovery points that are bolted to existing captured threaded nuts which must be engineered because Toyota kindly provided them. The fitted recovery points are bright yellow so I assume that they are safe!! and that a kind fellow 4wheeller will help pull me out using my unknown to them rated snatch strap!!
I think the key to any recovery is safety by fitting a least 1 but preferably 2 dampeners on recovery rope/straps.
Post by: KingBilly on June 25, 2017, 09:25:59 AM
KB
Post by: oldmate on June 25, 2017, 10:04:14 AM
I'm a civil engineer as a matter of fact, so I may have more knowledge on the strength of steel components and fastening systems than you assume I do.Yep. Cool. Engineer. I'll stop now.
My point was that a recovery/tow point does not have to be bolted on, or to have been destruction tested in order to be suitable for using in a snatch recovery. You are correct that welding and bolting are different, but your apparent belief that one is superior to the other is simply wrong. Both methods are used in construction and either can provide the required strength.
I agree which your point, that in the absence of testing, I can't be sure of the exact failure capacity of the factory tow points. What I have done however is measured those points and compared them to after market rated points. I'm confident, particularly if an equalising bridle is used, they are adequate for a snatch recovery. I would always use a dampener (or two) on the strap btw.
Also, what Pete just said....
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Post by: achjimmy on June 25, 2017, 10:09:09 AM
Can anyone point to any vehicles with factory fitted "rated" recovery points?
All this stamped 'rated' stuff means absolutely zero.
You can buy a hook with a number stamped on it and bolt it to any chassis with M12 high tensile bolts and it means nothing as far as ratings go.
Y
As a boilermaker I can grab a 50 ton lifting lug and weld to to a steel plate with a 3 run fillet weld and stamp it with my numbers, but it means nothing if that plate is 1.5mm thick and only tack welded to the rest of the load.
As far as I know there are no 'rated' recovery points fitted on any vehicles, plenty of meaningless numbers stamped on things though....
I'm a civil engineer as a matter of fact, so I may have more knowledge on the strength of steel components and fastening systems than you assume I do.
My point was that a recovery/tow point does not have to be bolted on, or to have been destruction tested in order to be suitable for using in a snatch recovery. You are correct that welding and bolting are different, but your apparent belief that one is superior to the other is simply wrong. Both methods are used in construction and either can provide the required strength.
I agree which your point, that in the absence of testing, I can't be sure of the exact failure capacity of the factory tow points. What I have done however is measured those points and compared them to after market rated points. I'm confident, particularly if an equalising bridle is used, they are adequate for a snatch recovery. I would always use a dampener (or two) on the strap btw.
Also, what Pete just said....
Yep both excellent posts.
Having come from avaiation engineering. Iam always amused at the "rated " aftermarket recovery points offered. Rated by who? Shackles yep purchased from a reliable source and straps again from a respected source but the rest is just a lottery imo.
Post by: achjimmy on June 25, 2017, 10:22:35 AM
Then I looked back over all the years I have owned a 4B.
Which is since I was about 19 or 20.
Up to about 15 Years ago I was recovering off the tow ball. Didn't know any better.
Think we have all been here at some time. Personally I have always held a aversion to snatching. I just always hated the concept, gentle tow or winch has been my perffered option but I understand why it works.
But it begs the question are tow balls crap today? Any learned metal tradesman or engineer can tell you that if a ball is made of quality steel and given its 3/4" / 19mm at its wasted point it has the ability to take an enormous load? More than a hitch pin !
I look at the humble tow ball today and the cut thread as opposed to rolled thread and the sharp finish to the shank as opposed to a large radius (all stress raises) and think what a POS surprised we don't hear about towing issues with modern heavy vans.?
I am not for one minute advocating that anybody start using towballs for recovery btw
Post by: Merts on June 25, 2017, 10:27:19 AM
Yep. Cool. Engineer. I'll stop now.
Good. I think we'd all appreciate that. :D
Post by: DrewXT on June 25, 2017, 10:41:10 AM
They were pulled until the point where we wanted them to be WLL rated, and to total destruction. At total destruction, they were still attached to the chassis rail.
Total destruction for one side was over 20 tonne, the other was over 18. We have rated (in a pair) to 6,000kg WLL, based on engineering assessment of the design, materials used, and method of assembly (jig assembly and welding) and attachment to the vehicle.
What our design, engineering assessment and testing can never take into account is if they are used for single side pull, shackles that are not WLL rated, or the nut doing the tow part of the recovery, even though we have a 3x safety factor.
It's worth noting that most "recovery points" are bench tested whilst bolted to a solid mass of steel, so in our opinion this would not have been a valid test, as everyone bolts a recovery point to a chassis!!
We are confident we've done everything in our power to release a product to the market that is safe, and have spent 18 months of design and testing extensively them on our own vehicles as well as bench/sled testing prior to releasing them.
We do not drill any new holes in the chassis, we use crush tubes where required and existing manufacturer holes, and use 15 bolts between the two sides of the vehicle. Captive nuts provided by the manufacturer are prone to failure.
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Post by: KingBilly on June 25, 2017, 10:49:33 AM
We recently released a set of recovery points to the market, and we had them tested at Nobles on their test sled, with each recovery point bolted to the same section of chassis they would be installed on when sold to the customer.
They were pulled until the point where we wanted them to be WLL rated, and to total destruction. At total destruction, they were still attached to the chassis rail.
Total destruction for one side was over 20 tonne, the other was over 18. We have rated (in a pair) to 6,000kg WLL, based on engineering assessment of the design, materials used, and method of assembly (jig assembly and welding) and attachment to the vehicle.
What our design, engineering assessment and testing can never take into account is if they are used for single side pull, shackles that are not WLL rated, or the nut doing the tow part of the recovery, even though we have a 3x safety factor.
It's worth noting that most "recovery points" are bench tested whilst bolted to a solid mass of steel, so in our opinion this would not have been a valid test, as everyone bolts a recovery point to a chassis!!
We are confident we've done everything in our power to release a product to the market that is safe, and have spent 18 months of design and testing extensively them on our own vehicles as well as bench/sled testing prior to releasing them.
We do not drill any new holes in the chassis, we use crush tubes where required and existing manufacturer holes, and use 15 bolts between the two sides of the vehicle. Captive nuts provided by the manufacturer are prone to failure.
And your company is?
KB
Post by: KingBilly on June 25, 2017, 10:52:21 AM
Yep. Cool. Engineer. I'll stop now.
Haha, civil engineer gazumps chippie. Don't stop now, love to read some more ;D need a good Sunday laugh.
KB
Post by: oldmate on June 25, 2017, 10:59:02 AM
We recently released a set of recovery points to the market, and we had them tested at Nobles on their test sled, with each recovery point bolted to the same section of chassis they would be installed on when sold to the customer.
They were pulled until the point where we wanted them to be WLL rated, and to total destruction. At total destruction, they were still attached to the chassis rail.
Total destruction for one side was over 20 tonne, the other was over 18. We have rated (in a pair) to 6,000kg WLL, based on engineering assessment of the design, materials used, and method of assembly (jig assembly and welding) and attachment to the vehicle.
What our design, engineering assessment and testing can never take into account is if they are used for single side pull, shackles that are not WLL rated, or the nut doing the tow part of the recovery, even though we have a 3x safety factor.
It's worth noting that most "recovery points" are bench tested whilst bolted to a solid mass of steel, so in our opinion this would not have been a valid test, as everyone bolts a recovery point to a chassis!!
We are confident we've done everything in our power to release a product to the market that is safe, and have spent 18 months of design and testing extensively them on our own vehicles as well as bench/sled testing prior to releasing them.
We do not drill any new holes in the chassis, we use crush tubes where required and existing manufacturer holes, and use 15 bolts between the two sides of the vehicle. Captive nuts provided by the manufacturer are prone to failure.
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According to this thread. You've wasted your time and money. Clearly consulted the wrong engineer
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Post by: DrewXT on June 25, 2017, 11:01:58 AM
And your company is?Net4x4 - we started off specialising in design and manufacture of accessories for the Amarok with local materials and trades.
KB
We have co-designed Australia specific Bilstein and H&R suspension for the vehicle with both factories in Germany, and have supply arrangements with most of the big accessory manufacturers, and can fit (in Melbourne) or arrange fitting of any accessory to pretty much any vehicle.
Every product we make or sell has to be good enough to go on our own vehicles or we won't sell it to you.
It's a small business, with my mate being the owner, and our focus being 100% satisfaction from our customer.
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Post by: KingBilly on June 25, 2017, 11:04:00 AM
Net4x4 - we started off specialising in design and manufacture of accessories for the Amarok with local materials and trades.
We have co-designed Australia specific Bilstein and H&R suspension for the vehicle with both factories in Germany, and have supply arrangements with most of the big accessory manufacturers, and can fit (in Melbourne) or arrange fitting of any accessory to pretty much any vehicle.
Every product we make or sell has to be good enough to go on our own vehicles or we won't sell it to you.
It's a small business, with my mate being the owner, and our focus being 100% satisfaction from our customer.
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That is great to hear. Love it when I read about an innovative Aussie company. Wish you and your mate every success.
KB
Post by: DrewXT on June 25, 2017, 11:07:59 AM
That is great to hear. Love it when I read about an innovative Aussie company. Wish you and your mate every success.Thanks mate - we both enjoy it, and have had customers come from as far as Townsville and Perth for us to work on their cars, and we're exporting our products so we think we're doing something right!
KB
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Post by: achjimmy on June 25, 2017, 12:53:07 PM
We recently released a set of recovery points to the market, and we had them tested at Nobles on their test sled, with each recovery point bolted to the same section of chassis they would be installed on when sold to the customer.
They were pulled until the point where we wanted them to be WLL rated, and to total destruction. At total destruction, they were still attached to the chassis rail.
Total destruction for one side was over 20 tonne, the other was over 18. We have rated (in a pair) to 6,000kg WLL, based on engineering assessment of the design, materials used, and method of assembly (jig assembly and welding) and attachment to the vehicle.
What our design, engineering assessment and testing can never take into account is if they are used for single side pull, shackles that are not WLL rated, or the nut doing the tow part of the recovery, even though we have a 3x safety factor.
It's worth noting that most "recovery points" are bench tested whilst bolted to a solid mass of steel, so in our opinion this would not have been a valid test, as everyone bolts a recovery point to a chassis!!
We are confident we've done everything in our power to release a product to the market that is safe, and have spent 18 months of design and testing extensively them on our own vehicles as well as bench/sled testing prior to releasing them.
We do not drill any new holes in the chassis, we use crush tubes where required and existing manufacturer holes, and use 15 bolts between the two sides of the vehicle. Captive nuts provided by the manufacturer are prone to failure.
Sent from my Nexus 6P using Tapatalk
Brilliant mate well done. It deserves to be shouted from the roof tops ..
Post by: BaseCamp on June 25, 2017, 03:29:25 PM
We recently released a set of recovery points to the market, and we had them tested at Nobles on their test sled, with each recovery point bolted to the same section of chassis they would be installed on when sold to the customer.
They were pulled until the point where we wanted them to be WLL rated, and to total destruction. At total destruction, they were still attached to the chassis rail.
Total destruction for one side was over 20 tonne, the other was over 18. We have rated (in a pair) to 6,000kg WLL, based on engineering assessment of the design, materials used, and method of assembly (jig assembly and welding) and attachment to the vehicle.
What our design, engineering assessment and testing can never take into account is if they are used for single side pull ....
### Id be interested to know why you couldn't have/didn't test your products via:
(a) a single sided, (one recovery point), pull? I note from above that you say that was not done?; (b) does that mean you only sell them in sets of 2 then; with a warning label not to use them singularly/untested for this?; (c) did you do a "yank test" - NO, not attaching them to a Jeep
####
(ps: I'm not associated in any way with the 4wd aftermarket accessories industry, and am not an engineer) ..
It's worth noting that most "recovery points" are bench tested whilst bolted to a solid mass of steel, so in our opinion this would not have been a valid test, as everyone bolts a recovery point to a chassis!!
We are confident we've done everything in our power to release a product to the market that is safe
Sent from my Nexus 6P using Tapatalk
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Post by: MadMarv on June 25, 2017, 05:13:54 PM
Post by: Bird on June 26, 2017, 09:45:45 AM
https://www.facebook.com/Utopialandscapingandpools/videos/1492744554117163/ (https://www.facebook.com/Utopialandscapingandpools/videos/1492744554117163/)
Post by: DrewXT on June 26, 2017, 10:35:54 AM
### Id be interested to know why you couldn't have/didn't test your products via:
(a) a single sided, (one recovery point), pull? I note from above that you say that was not done?; (b) does that mean you only sell them in sets of 2 then; with a warning label not to use them singularly/untested for this?; (c) did you do a "yank test" - NO, not attaching them to a Jeep - but a real world test where Nobles applies an instant (say 6tn+) load on the RPs - at say the equivalent of 30km/h+ velocity.... to see what happens next?
####
(ps: I'm not associated in any way with the 4wd aftermarket accessories industry, and am not an engineer) ..
To answer your above:
* We did a pull test per section, e.g. per side
* Yes, we only sell them in pairs, and we are very clear with our instructions, and selling that they are NOT intended to be used as a single pull point - of course, you can't prevent people doing stupid things - we have had requests to sell a single point, and we won't do that, as it's not in the best interest of the owner or the structural integrity of the vehicle.
* There's no such thing as a "yank test" when WLL rating a product - it's based on a constant increasing load being applied until the product fails. That being said, these have been tested in the wild with a fully loaded vehicle and camper behind, being recovered via gentle pull (not snatched).
Without sounding condescending, snatching ('here we go, watch this, get up it and rip it' - style) is really the uneducated 4WD'ers way of recovering a vehicle that's stuck. It's the YouTube method, and is one of the most attributed methods to causing death in the 4WD community :( Between the two of us, we've been driving 4WD's for a collective 60+ years, and neither of us have ever recovered a vehicle that way.
Post by: Rumpig on June 26, 2017, 11:12:33 AM
No damper nothing. this is askin for trouble...plenty of comments on there making out like he's a hero, yet nobody commenting on the lack of a simply addition that you mention that could make the recovery safer....even though his tow point and strap are likely being used way beyond their design scope.
https://www.facebook.com/Utopialandscapingandpools/videos/1492744554117163/ (https://www.facebook.com/Utopialandscapingandpools/videos/1492744554117163/)
Post by: KingBilly on June 26, 2017, 11:18:14 AM
plenty of comments on there making out like he's a hero, yet nobody commenting on the lack of a simply addition that you mention that could make the recovery safer....even though his tow point and strap are likely being used way beyond their design scope.
Plus he has done multiple heavy duty snatches with the same strap. You can actually see it is losing its elasticity with each attempt. After a couple of attempts, you need to change to another strap otherwise you have lost the benefit of using a snatch strap.
KB
Post by: UIZ733 on June 26, 2017, 11:27:56 AM
https://www.youtube.com/watch?v=YTNC41V4EB0 (https://www.youtube.com/watch?v=YTNC41V4EB0)
Post by: BaseCamp on June 26, 2017, 05:02:10 PM
Sounds like you have a quality product on your hands there.... I'll look at getting a couple of pairs myself. ..... and I know what you mean about the "charge at it" type of recovery using a snatch strap, (as often seen on you tube)........ I have found personally - that a "yank it out recovery" is unnecessary; (beach and track work) - and fails Roothy's vehicle sympathy test ....
BaseCamp
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Post by: NewieCamper on June 26, 2017, 06:30:03 PM
plenty of comments on there making out like he's a hero, yet nobody commenting on the lack of a simply addition that you mention that could make the recovery safer....even though his tow point and strap are likely being used way beyond their design scope.Didn't check the comments, but what do you reckon the strap is rated for? I've seen 8tonne and 12tonne available. What does the truck weigh? Probably 12 empty, and the barrel is going, so it's probably not empty.
Post by: Rumpig on June 26, 2017, 06:49:26 PM
Didn't check the comments, but what do you reckon the strap is rated for? I've seen 8tonne and 12tonne available. What does the truck weigh? Probably 12 empty, and the barrel is going, so it's probably not empty.yeah with the aggi spinning i was also wondering how full it is, no need to spin if it was empty.
Post by: Squalo on June 27, 2017, 03:45:48 PM
But it begs the question are tow balls crap today? Any learned metal tradesman or engineer can tell you that if a ball is made of quality steel and given its 3/4" / 19mm at its wasted point it has the ability to take an enormous load? More than a hitch pin !
I look at the humble tow ball today and the cut thread as opposed to rolled thread and the sharp finish to the shank as opposed to a large radius (all stress raises) and think what a POS surprised we don't hear about towing issues with modern heavy vans.?
I am not for one minute advocating that anybody start using towballs for recovery btw
There is a big difference in the forces involved with static loading and shock loading, this is why towballs don't fail when towing, but shear when shock loaded.
Post by: The punter on June 27, 2017, 03:52:33 PM
Any learned metal tradesman or engineer can tell you that if a ball is made of quality steel and given its 3/4" / 19mm at its wasted point it has the ability to take an enormous load? More than a hitch pin !
I look at the humble tow ball today and the cut thread as opposed to rolled thread and the sharp finish to the shank as opposed to a large radius (all stress raises) and think what a POS surprised we don't hear about towing issues with modern heavy vans.?
I am not for one minute advocating that anybody start using towballs for recovery btw
Learned metal tradesman here, the issue is the fulcrum load under tension.
Post by: achjimmy on June 27, 2017, 08:19:23 PM
There is a big difference in the forces involved with static loading and shock loading, this is why towballs don't fail when towing, but shear when shock loaded.
Ofcourse it is different load, but do towballs not fail while towing? General towing would still not be a static load would it?
Learned metal tradesman here, the issue is the fulcrum load under tension.but there is also often a fulcrum load on a recovery point too?
The last couple of towballs I've looked at are fudmentally wrong imo. They have no root radius they had cut threads (not rolled) terminating with a terrible sharp stress raiser sometimes chatter, And then we never use a flat washer under the spring washer that would enable the correct torque to be properly applied and allow the thread to stretch?
Just saying I think towballs them selves are flawed? They work for the average application because they are over stressed for that purpose. A few 5/16" HT bolts hold the wings on planes capable of aerobatics so a 19mm lump of steel can take a 3.5t load even relatively mildly applied.
If they were of quality steel made to proper engineering standards and fastened to the hitch with a correct torque/stretch they would be a darn site stronger and capable of acting as a hook or fulcrum point for far higher loads ??? Imo :-)
Basically the humble towballs are Shit and more so today cause any Chinese Manufacturer seem to stamp them and sell them through any number of sources
Post by: prodigyrf on June 27, 2017, 10:31:26 PM
There is a big difference in the forces involved with static loading and shock loading, this is why towballs don't fail when towing, but shear when shock loaded.
Well the breaking strain is the breaking strain whether it's applied statically or dynamically ie by simply loading up a suspended weight to that limit or applied by a snatch strap. The real problem lies in a 3.5T towball apparently not having much swl above that and then you have 8T and 10T rated snatch straps that can easily overload it. Then you might say aha but wouldn't a heavy trailer act like a snatch strap momentum wise sometimes and exceed that? Mostly not because you have rolling wheels and our tugs just don't have the torque to achieve that except with a runup as in snatching. It's why autos are often rated higher for towing than manuals and there's a pretty good discussion about all the considerations here- http://www.4wdaction.com.au/forum/viewtopic.php?f=10&t=137657 (http://www.4wdaction.com.au/forum/viewtopic.php?f=10&t=137657)
Post by: prodigyrf on June 27, 2017, 10:42:23 PM
Post by: Wunderlust on June 27, 2017, 11:31:41 PM
Ofcourse it is different load, but do towballs not fail while towing? General towing would still not be a static load would it?A 3.5tomne towball does not mean it has the capacity for 3.5te. Tow balls are there primarily to support the towball weights plus the forces associated with pulling your trailer (and breaking), not hanging a 3.5te off it.
but there is also often a fulcrum load on a recovery point too?
The last couple of towballs I've looked at are fudmentally wrong imo. They have no root radius they had cut threads (not rolled) terminating with a terrible sharp stress raiser sometimes chatter, And then we never use a flat washer under the spring washer that would enable the correct torque to be properly applied and allow the thread to stretch?
Just saying I think towballs them selves are flawed? They work for the average application because they are over stressed for that purpose. A few 5/16" HT bolts hold the wings on planes capable of aerobatics so a 19mm lump of steel can take a 3.5t load even relatively mildly applied.
If they were of quality steel made to proper engineering standards and fastened to the hitch with a correct torque/stretch they would be a darn site stronger and capable of acting as a hook or fulcrum point for far higher loads ??? Imo :-)
Basically the humble towballs are Shit and more so today cause any Chinese Manufacturer seem to stamp them and sell them through any number of sources
Post by: tryagain on June 27, 2017, 11:46:50 PM
or force equals mass multiplied by acceleration, with a snatch strap assuming the vehicle is 3000kg travelling at 15km/h and the force of the strap is taken up over .25second A=16.667m/s^2 so the force is 3000kgx16.667m/s^2= 50000N or 5102kg
In a normal towing situation, you don't have the difference in acceleration so it is just the weight you take into consideration.
Post by: Chris. on June 28, 2017, 06:15:03 AM
Post by: GUEY on June 28, 2017, 12:10:58 PM
It's worth noting that factory tow points and factory tie down points are completely different things. Some tow points (such as the ones on my MQ Triton) are suitable for recoveries. Tie down points certainly are not.
I'm only a cabinetmaker ( so at least one step up from a chippie... >:D) but if they are the same style as the front of my Colorado, that is a bit of steel bent into a u shape and welded to the chassis, they don't fill me with a whole lot of confidence.
In saying that, as Rumpig posted in his video, the force that would be required to break them shouldn't be needed to extract the vehicle anyway if the right prep work is done before snatching.
Don't know if the link has been posted, but for anyone that has flakebook, checkout "I got bogged at inskip point".
While I do have a chuckle, I am constantly amazed that Darwin doesn't have more entries to his awards every year...
Post by: Merts on June 28, 2017, 12:30:58 PM
I'm only a cabinetmaker ( so at least one step up from a chippie... >:D) but if they are the same style as the front of my Colorado, that is a bit of steel bent into a u shape and welded to the chassis, they don't fill me with a whole lot of confidence.
In saying that, as Rumpig posted in his video, the force that would be required to break them shouldn't be needed to extract the vehicle anyway if the right prep work is done before snatching.
Don't know if the link has been posted, but for anyone that has flakebook, checkout "I got bogged at inskip point".
While I do have a chuckle, I am constantly amazed that Darwin doesn't have more entries to his awards every year...
Can't comment on the Colorado points as I've not looked at them, but that's why I said 'some' factory tow points are suitable.
People need to be thoughtful and careful regarding what they decide to use (and how they use them) for recoveries.
My view on snatch recoveries is that they should be a last resort, and they should be done as gently as possible to reduce the risk of breaking something, regardless of whether you are using factory points or rated aftermarket ones.
Post by: Rumpig on June 28, 2017, 05:44:27 PM
People need to be thoughtful and careful regarding what they decide to use (and how they use them) for recoveries.gotta agree...even though i helped make that video, I'll grab a set of Maxtrax for a beach recovery long before I dig out the snatch strap.
My view on snatch recoveries is that they should be a last resort, and they should be done as gently as possible to reduce the risk of breaking something, regardless of whether you are using factory points or rated aftermarket ones.
Post by: prodigyrf on June 29, 2017, 12:14:19 AM
gotta agree...even though i helped make that video, I'll grab a set of Maxtrax for a beach recovery long before I dig out the snatch strap.
Yes it does make you wonder with many of those snatch vids why on earth they don't do some serious digging out in front of the wheels instead of trying to yank them out without any prep. You had to shake your head at the clowns who managed to pull the front end right out of that one buried in the mud.
Post by: NewieCamper on June 29, 2017, 08:13:05 AM
recjon I'll also be taking a digging device too, and probably some treated pine 'max trax' in case no one is around for assistance.