Snatch Straps & Towballs

Thanks Steve, I will check the mag out. By rams horn do you mean the device
for attaching safety chains ? I have broken several straps & they invariably go
straight under the vehicle at a rate of knots, either forward or back depending on the site of break....oldbaz

Yeah Oldbaz,

It had two pieces of 5/8 rod coiled up like a rams horn and welded to the tow bar. I foolishly thought it would be strong enough to withstand the snatch... oh boy was I wrong on that one.

Steve.

Howard, sorry to hear of your sad experience. I was not condoning or recomending the practice, just seeking information...oldbaz.

I bother to find out so that I may be a better informed person. Isnt that why people
ask questions on this forum ?.....oldbaz.

Thanks for the info, While being aware that this was generally considered a
no no, I had not seen any direct evidence, but obviously this does cause
problems. cheers...oldbaz.

Brian, like you I had only anecdotal evidence of the dangers involved, but as you can see, people have experience of the results of this action & I am now convinced.
Your option with the recovery hook & not needing shackles would seem a most
effective alternative. Thanks for your input...oldbaz.

I am interested in knowing you attach a tow hook permanantly to an old hitch?

I have seen the commercially avail receiver hitches but can't work out how you would attached the hook to the tongue

David,

I think they bolt the hook to the square section....NOT the flat tongue that the towball would normally bolt onto. You'd need to obtain a suitable length of the 50mm (?) box section, or butcher a proper goose-neck by cutting off the flat bar.

I wouldn't trust the flat bar section.....some blokes use a shackle through the tow-ball's hole........to me, this just adds another potential breaking point (ie: the weld between the flat bit and the box section).

The hook bolted to the box section is probably as safe as simply attaching the snatch strap to the square housing of the towbar, using the retaining pin, although that pin is less-likely to be bent if the square-section plus hook is used as the main area for stress is in the "sheer" of the pin, whereas with the strap in the square hole, the stress is on the centre of the pin and I've heard of them bending (but never witnessed this).

Cheers

Roachie

yeh roachie I know how the bought ones are made. I was a bit concerned that as he said he used an old towbar tongue that he may have welded a hook to it which would be a disaster waiting to happen.

Think Barry's question is a bit macabre actually.

I have been given a butt plug actually. No, not one of those, but a solid square steel piece with a heavy duty shackle through it ready to yank a Yota. I usually just have a pin through the square section.

David, that does sound a worrying tone.

Outnabout David,
We are taught to use a rated shackle to attach the strap to the tongue of a tow bar. I know that in other states, this isn't taught, and as I understand it, other states (not sure where) are taught to attach the strap via the pin in the hitch receiver. Comes down to who is shown what according to who's standards I guess. But anyway, here on the Gold Coast, and as far as I know, in Queensland, that's the way it is. So I had a spare tongue, not a rusty old one that was ready for the bin or anything but a spare one in good order. I went to ARB and bought a rated recovery hook, replaced the high tensile nuts and bolts that come in the pack with higher grade high tensile nuts/bolts, drilled holes in the tongue, the flat bit that would normally hold the tow ball, and attached the recovery hook to it that way. Works a treat! And doesn't utilise a shackle! Although I guess the chances of a rated shackle coming off are about the same as the hook coming off. I didn't come up with this idea, I copied from some others that I had seen but sure do wish that I had applied for a patent on it as there are a few variations on this idea nowadays.
The other thing is that, in my experience, snatch recovery's don't need to be performed at break neck speed. In fact the easiest recovery's I have participated in have been the tow vehicle slowly driving forward, stretching the strap which then transfers the stored energy to the "recovered" vehicle and voila! Un-stuck fourby!

Roachie,

I have seen a pin that was bent by a strap, probably the result of a recovery performed with far too much throttle. I agree that with the tongue in, the pin is being used in the way it was designed, not with the entire load exerted on the centre of the pin.

Our club's Driver Awareness Program is (again, to the best of my knowledge) based on the National Code. But this debate comes up a fair bit as far as whether to use the pin or a shackle (or in my case a recovery hook) to hold the strap. If I didn't have my hook/tongue, or a shackle I wouldn't hesitate to try the strap-down-the-hitch-centre-and-use-the-pin-to-hold-it trick, but I would NEVER, EVER drape o strap over a tow ball.

Cheers

Brian

Fair comment, following the info received I shall certainly mend my errant ways..
cheers...oldbaz.

Your thoughts are similar to mine, but in light of all info received I shall desist in
future & I thank you for your input....oldbaz.

Cark, that'd soil your Jocks.

Geoff

Rob, Not having a go at you but the statement about towballs not being rated for horizontal forces is rubbish. The vertical force on a towball is max 350-400kg for a 3.5tonne trailer.....a 2" piece of 4mm rod will hold that up.

Towballs are purely rated on the horizontal force applied such as in accellerating and braking when all the force is being applied horizontally thru the towball. How much shock load do you reckon goes thru a towball when you are on and off the throttle???

Look I'm far from promoting the use of towballs as a recovery hook but there is alot of BS floating around about them.

Would people use a pintle hook as a recovery point??? Whats the difference??

"Towballs are purely rated on the horizontal force applied such as in accellerating and braking when all the force is being applied horizontally thru the towball. How much shock load do you reckon goes thru a towball when you are on and off the throttle??? "

Nowhere near as much as when performing a snatch recovery I would think. Snatch straps are rated at 8500kgs, (some more)..... the shock load on a tow ball would be way past it's rating in my opinion. I am happy to stand corrected on that though.

Cheers

Brian

Hi Brian,

Not doubting you there mate. If you were doing a snatch that was going to excert up to the max breaking strain of the snatch strap it wouldn't matter what you had it attached to ...I'd be very worried.

The other thing in "defence" of the towball is that the loads applied to it are shock loads when towing (ie hard braking) whereas a snatch strap applies a "progressive" (although still relatively quick) force.

It would be interesting to see how much horizontal force is applied to a towball if you were towing a 700kg (unbraked) trailer at 110km/h and slammed on the brakes????? Someone may be able to do the calcs on it, but I reckon we'd all be shocked at what that force is......and they obviously have to be able to withstand that force with a good factor of safety aswell.

I'm not doubting that towballs have broken in recovery excercises but I bet the towball was a cheap one......a bit like how much strain you can but on a $2 spanner and a $25 spanner

"The other thing in "defence" of the towball is that the loads applied to it are shock loads when towing (ie hard braking) whereas a snatch strap applies a "progressive" (although still relatively quick) force. "

The fact that the trailer is constantly connected to the towball doesn't allow 'shock' loads. While they may be sudden, they are applied at the same rate they are applied to the vehicle. Further, the trailer is (generally) a rolling load. Whilst you may be able to tow a 3.5 tonne trailer, it is a very different thing to pulling out a bogged vehicle.

"Snatch strap applies a progressive force...." only once it has taken up slack. A lot of the time when you are in boggy areas the recovering vehicle has difficulty taking off at a crawl, so there is in fact a shock load applied.

"I bet the towball was a cheap one......" And where do you actually buy expensive towballs? I bet the majority of towballs are constructed out of very similar grade steel, with the only thing I know of having changed being the diameter of the thread.

Whilst I have never seen a towball snap, I have seen some *unnamed government organisation* attempt some vehicle recovery using a combination of snatch straps, chains and ropes, and seen the rate at which they cover a couple of hundred metres from a standing start. Try doing a towball recovery near me and I won't be very pleasant to you at all.

Sorry Hughesy, I have to say I'm still against towballs as a recovery point. Trailers connected to the towball wouldn't exert a great deal more shock load to the towball than it is already experiencing I would think, simply because the trailer is connected via a solid draw bar. When a snatch stfrap is used, "most" people drive off a breakneck speed, the strap does it's stretchy thing and then at the end of the "stretch", the other vehicle should emerge from whatever has it bogged. BUT, if the stuck vehicle is really stuck, then everything comes to a sudden STOP! And all of that pent up energy has to be released somewhere. And my bet would be the tow ball, again simply because it is designed to "tow" and not "recover".

Cheers

Brian

RobA, thanks for your input. I am not competent to enter into the load/force
arguments above, but suffice to say the info gleaned from you & others will see a
change in my recovery strategy & I appreciate everyones opinion....oldbaz.