Attaching Strap to Towbar

I totally agree. I am no engineer but the image 2 appears to load the ball trying to pull it off. It would be only maginally better than straight on the ball. Image 3 looks fine if it is kept in that position which it may not if the direction of pull was altered slightly.

It is so simple to just remove the hitch and use the pin in the receiver by itself. Safe and simple.

Alan

Image 2 was arranged with the strap raised from the tongue to show the layout of the strap. In actual fact, when even a light load such as a manual pull is applied, the sides of the strap embracing the ball position themselves low on the base of the ball, flat on the tongue. This then places no bending moment on the ball stem, it merely serves to keep the strap crossed over so as to maintain the loop around the tongue.

I also would normally use the pin in the receiver of the hitch, if for no other reason than I travel without the tongue fitted. However, not all towbars have removable tongues and this method allows safe attachment of a strap to such bars rather than to a vehicle point which may not be appropriate for towing. Also with many towbars the tongue may have been removable when new but has long since become rusted in position.

Without an option such as this, some people with non-removable tongues may be tempted to simply drop the strap over the ball even if they have been warned of the danger. Better that they are given an option which is safe.

As an engineer, I would asses that there is little to no load tending to bend the ball stem with my proposed method. In extremes, the strap would break before any such problem. Mind you after witnessing some snatch recoveries, it was a wonder that the whole towbar did not part company from the vehicle! Many people do not understand the physics involved in the use of an elastic snatch strap.

Well OK WildOne! No need to keep repeating yourself!!

The problem with just putting the strap around the ball is that it reposes in the hollow which is some 25mm above the tongue. Hence there is a force imposed that tends to bend the threaded section of the ball thus shearing it.

With my method there is no force other than a squeeze on the ball, it merely serves to keep the strap apart. The pulling force is directly on the tongue with the nut resisting any tendency for the strap eye to slide. Being close to the tongue. the nut would easily resist any load that the strap could impose. It is applied engineering principles.

There is a bad echo in here isn't there. LOL

I agree with Wild100
To be sure, to be sure, to be sure
Roflmao

Cant help the 3 copies, I reply once and get 3 posts
But this type of method is just asking for some in-experienced person who gets it wrong or in the dark, doesnt connect it correctly and we have another snatch strap death, better to just use the proven tested safe methods

It has been said that if you keep repeating an expression, people may come to believe it! LOL

Your duplicate postings have now been removed Wild100 :)

Modsquad

Al I reckon you are spot on here, there are no fulcrum loads on the bal in either of your solutions

By the way are there really three L's in your name? To be sure to be sure to be sure???

Thanks Bonz. I'm glad some can perceive the physics involved. But there were some good points re sharp edges of the tongue. However it was presented as a fall-back option, not a preferred way.

Re the name........ you are the first to pick-up on the three L's since I put it there. I got tired of people leaving out one "L" and calling me "Alan" so I put a spare one in, LOL. It seems to have worked...... every response in this thread using my name has used two "L's". I note you played it safe and used simply "Al". Maybe I'll switch to that, it sounds nice.

On the same theme, no-one has commented on my rather improbable profile picture. Perhaps they do not want to embarrass me!

I thought you were drowning a Toyota, which is entirely honorable and in no need of comment !

I'm with Alan on this one, I'm no engineer in physics either but I can see quite plainly there would NO strain on the Ball.... all that will happen is the poor little bugger will be choked.
Brilliant Alan...bloody brilliant.

.

Allllan
Just looking at the pics again and my previous comment is for the drop tongue, and so's this one, it looks good especially if you have something like those chain links to stop it from sliding down, maybe a little testing on a drop bar without those links would be interesting to see the results.

.

Paj, In response I would offer:

a) There should not be any nylon webbing in contact with the tongue. Any half-decent strap has leather reinforcing on the eye.
b) Any heat generated is due to the deformation (stretching) of the strap. No stretching takes place in the reinforced loop section. Hence no heat here.
c) Granted that the tongue may be offset. However the towbar assembly is rated to take this into account and be capable of managing the typical 2 ton or so towing load which incorporates high impulse forces due to jerking motions. I would think properly conducted snatch recoveries to impose no greater loads.
d) What is your scientific source for this assertion?

The methods "mentioned so far" are not always available leading people to unsafe alternatives. Be assured that my proposed alternate method has been considered carefully from an engineering perspective.

Hi Allan,

I understand where you're coming from and with an engineering background you'd have a much better idea than me. It would be worth setting your system up on a test bed to see the result.

I've had snatch straps and equalizer straps on a static test bed to check performance. With the equaliser straps the protective sleeve was cut through under heavy load in every case, and in a number of cases the heat generated melted the strap at the eye although not enough to cut right through - nylon on nylon maybe; I'm not qualified to determine why but the physical proof was clear. Most straps that I've seen feature a synthetic reinforced eye rather than leather hence my comment.

With the offset tongue there are many non Reece style fixed tow hitches that are definitely not rated to 2 tonne - I had a choice of a fixed 750kg or a 2.5T when I purchased my vehicle - which could result in disaster should someone not know the difference.

There has been formal testing carried out on wet snatch straps and their capacity was reduced by a great amount - it was published either 2009 or 2010, but I can't remember who the tester was. If I find it again I'll submit it. I think twisted straps were also tested in the same article, as was colour dyes.

I can't argue from an engineers point of view as I'm not qualified to do so. If your method saves the life of someone who doesn't have the correct gear then that's a bonus and I guess that's what you're suggesting.

Hi Paj, Thank you for an excellent thought-out response.

From the "Just Straps" website: "A wet strap may be 20% under strength, a damaged strap may break. Do not allow the strap to contact hot surfaces or sharp edges."........ Confirms your expression, although it is universal and I cannot see how that specifically relates to my proposal.

The edges of my tongues are rounded and not likely to cut the strap but I will concede that not all tongues may be so. Certainly there would be vehicles with towbars not rated to perform snatch recovery and there would be drivers not capable or caring of determining the adequacy of their towbar or any other component involved in recovery. I once witnessed someone attaching the strap to the safety-chain ring using the trailer shackle. When I offered my criticism I was told where to go in no uncertain manner........ so I did so and ******-off. I therefore was not around to see the outcome. I offer this as an example of how it is not possible to educate all drivers in safe practice.

My method certainly is an improvement over simply looping the strap over the tow-ball where no rated recovery attachments are available. Thanks again for your contribution.

Thank goodness for your vote MUZBRY. So far: 3 against, 3 doubtful, and 1 for.
Perhaps it takes a grumpy old man to appreciate the unrecognised and brilliant concepts of another irritable senior citizen?
Ah well, they didn't believe Einstein at first either.

Allan
Who's calling who grumpy????

I have used that method to tow a vehicle with a non snatch strap on many occasions. Including a stint as Clerk of Course at Hidden Valley raceway, Darwin.
Came to the same conclusion you have about stresses and loads plus it won't fall off if the strap slackens.

I prefer not to "snatch" but drive in low 2nd to the stretch of the strap then stop and use the stored energy in the strap to help the stuck vehicle drive out. Repeat as necessary. (hope that makes sense) Much gentler on vehicles and much safer.

Thanks Barry, Kimba's 'Receiver Shackle' is very good and appropriate for those who frequently need to snatch, or believe that they MAY need to frequently snatch. However, it is just another thing to have to purchase and carry.

I think some here have missed the point of my proposal. It is not suggested as an alternative for those who ARE equipped with appropriate recovery points but for those who do NOT have such and can be tempted into using the all-too-simple method of just dropping the strap over the ball. It is well established in industrial safety considerations that when faced with a safe procedure that is perceived as being "too much trouble" persons will frequently resort to unapproved methods which are perilous. An alternate procedure, perhaps not as exemplary but quite safe, is better than no substitute at all.

With many things there is an established ideal solution, sometimes with bells-and-whistles, but for those not possessing the bells & whistles, I have proposed a safe, simple alternative.

Definite NO from me.

Those who do not possess the "Bells and Whistles" should never attempt to snatch without the proper equipment.

As stated elsewhere pulling around a sharp angle is a NO NO as it would place a concentrated strain on snatch strap.

It might hold up once but I would never use the strap again as it would be suspect.

Bruce

Thanks Fisho.

You have my vote, have tried your method years ago amongst other methods, important thing is no sharp edges.
Cheers.

Alllen

You say in another post that your hitch has rounded corners, the hitch shown in the photo sure doesn't have rounded corners.

I agree with the comments regarding rigging, The ONLY time I have seen a rigging strap break below it's working load limit is when it is passed over a sharp angle as shown in your photos.

Perhaps if you used a forged hitch like this it may be OK but there is no way I would recommend it. This hitch is rated at 8,000Kg so it won't break.

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Bruce

Sorry gbc, about the twist in image 2. Clumsy of me.
This one better?
Image Could Not Be Found

The point still stands that there is nylon reeved over nylon which will create friction issues.
Don't get me wrong, if there were no other points of attachment, I'd do exactly what you've done, and have done in the past. But that still don't make it right ;)

Friction issues of "nylon on nylon" exist at a much higher risk when there is movement in one side eg rope situations...for this situation i would imagine very little wear would occur, and coupled with the infrequent use of the strap, the risk would be minimal if checked before, during and after use. The risk here is no higher than the well accepted technique of joining two snatch straps.

Andrew

ob.
Finally common sense has prevailed your "2 bobs worth " is the best yet.
It seems that some people are so intent to shoot others down at the drop of a hat,that they don't realise that Allan ( with 3 Ls ) has simply offered an alternative, for which I think is quite a good solution.
I for one would be more concerned about removing hitch, poke in eye of strap, then fit a shackle or bar, then have tow vehicle move on an angle to rub on 4 x sharp edges inside the hitch , and they ARE sharp from hitch movement.
Cheers
Paul

Image Could Not Be Found

I Haven't, but Ive had a bullbar impact against the heavy steel tray on one of my previous Landrover trayback utes.
An earlyish Toyota HJ45 was bogged to the axles on a rising tide on a beach near Northampton WA and he asked me to give him a tug.
i agreed, but only after he dug all the sand buildup away. I made sure that he was aware of the risks involved with a series Landrover towing a Landcruiser and asked the guy to fix his end of the snatch strap to his vehicle's tow hook.
"Oh I took it off when I fitted the bar, I'll attach it to the bar mounting brackets with a bridle strap . That should be solid enough".

"Are you sure it will be OK' sez me "It doesn't look too solid"
"Nah She'll be strong enough, and the tide is getting closer".
"OK then. Don't blame me if it all goes pearshaped

It wasn't.......so the 3inch channel at the back of the tray had some paint scraped off by the aluminium bullbar.

But we got out eventually and I got no thanks for my assistance.. I wonder why..

Disco
aka Tony

Alll ,my troopies hayman reese tongue has been flogged by years of towing trailers on corrugations and isnt coming out in a big hurry,i learnt a good lesson when letting a backpacker help me hook up our tour trailer(i didnt check what he had done),he hooked the safety chains to the Rclip on the pin,it pulled the clip and i lost the pin,drove for 3 hours on crappy corrugations and found the chain dragging on the ground when i pulled up,,,,trailer still intact luckily ,,found that the genuine toyota wheel spanner fits thru the hole nicely held in place with some duct tape,,so not everyone has a nice new 4wd whos tongue easily slips out and therefore your ALTERNATE method works just fine ,ive used this for a long time now and as long as you inspect the tongue for sharp edges or nicks all is good

You could ask the kid in Tassie who got killed by one that fired right through a Patrol and hit him in the head.

Several on Utube as well buried in the back of fourbys or shot right through the windscreen and all