Proper setup for a bridled (front) recovery point?

[FeatherWeightDriver]

Brains trust,

I'm looking for an updated front bridle setup for my Defender 110, and the more I thought about how it should work the more I got confused :eek:

On my 110 I have an APT steering guard, although it could just as easily be jate rings or an ARB front bar :angel:.

Assumptions (feel free to tell me if any of these are wrong):


if I have too short a bridle, the angles get too large, reducing the load at which the bridle will break
if I have too long a bridle, the bridle will turn a sharper angle at whatever it is attached to on the live side, also reducing the load at which the bridle will break
less metal in any recovery setup is better

So the questions are as follows:


is a bridle length of 2x the distance between the attachment points about right?
when connecting a bridle to the live end of the recovery, is a shackle preferable to fabric on fabric? Shackle is heavy (potential missile) but the fabric on fabric will likely wear faster.
If using a shackle, I assume the pin should be on the live side (not the bridle side)
If using a shackle, isn't the radius of the shackle a lot less than the 10x line diameter ideal? Apart from being heavier, is a snatch block better?
can I use a chain bridle instead of dyneema or webbing? It's heavy, but certainly not the weakest link in the recovery...

Thanks in advance,
FWD

[Tank]

Brains trust,

I'm looking for an updated front bridle setup for my Defender 110, and the more I thought about how it should work the more I got confused :eek:

On my 110 I have an APT steering guard, although it could just as easily be jate rings or an ARB front bar :angel:.

Assumptions (feel free to tell me if any of these are wrong):


if I have too short a bridle, the angles get too large, reducing the load at which the bridle will break
if I have too long a bridle, the bridle will turn a sharper angle at whatever it is attached to on the live side, also reducing the load at which the bridle will break
less metal in any recovery setup is better

So the questions are as follows:


is a bridle length of 2x the distance between the attachment points about right?
when connecting a bridle to the live end of the recovery, is a shackle preferable to fabric on fabric? Shackle is heavy (potential missile) but the fabric on fabric will likely wear faster.
If using a shackle, I assume the pin should be on the live side (not the bridle side)
If using a shackle, isn't the radius of the shackle a lot less than the 10x line diameter ideal? Apart from being heavier, is a snatch block better?
can I use a chain bridle instead of dyneema or webbing? It's heavy, but certainly not the weakest link in the recovery...

Thanks in advance,
FWD
A couple of hooks mounted top of your chassis rail (like the FJ/BJ Toyotas used to have, no shackles needed.
Or box the end of your chassis rails up to the back of your bulbar, insert 2 collared eyebolts, say 3T SWL each through the bulbar into the reinforced box section you have just constructed, eyes vertical allowing shackles to align with load and anchor point.
Bridle straps/slings/chains should be as long as practical to keep angle at 60 degrees or less, so if you have a metre between truck recovery points a 20' bridle should be AOK, Regards Frank.

[AndyG]

So with my ancient trigo, about 2.5 times the distance between the attachment points, would be a safe bet.

Looks like plenty of pre made ones on Ebay, but of course like all 4wd stuff, no SWL , but 12,000 kg advertised should cover it
And then I found this
http://www.l2sfbc.com/rmp/blog/recovery-force-bridle-winch-included-angle

[Tank]

The rules to remember when using a strap/sling/chain as a bridle setup is to keep the angle at the hook up point (top of the apex) as small as possible.
When you anchor the eyes of a strap to recovery points say a metre apart and your strap is only 2 metres long you will double the load on each leg of the strap and it will almost certainly break. So the same recovery points but using a strap say 10 metres or even 20 metres long will lessen the angle at the hook up point (apex).
The smaller the angle the less tension (stress) on the Strap, the strap is trying to pull your bogged Toyota in a forward motion and at the same time is trying to pull the 2 ends of the strap together, into a straight line with one another.
Try this, grab 2 house bricks, one in each hand, hold them down by your side, easy, could do it all day, now hold your arms out from your side at around 90 or even 120 degrees, not so easy, similar principle, gravity is pulling your arms back to your side, same as whoever is pulling on your bridle strap is trying first to pull the ends of the strap together in a straight line as well as pulling forward.
Keep your bridle strap as long as you can to minimise the angle, if necessary use 2 straps, Regards Frank.

[FeatherWeightDriver]

Thanks for the feedback folks!


Looks like plenty of pre made ones on Ebay, but of course like all 4wd stuff, no SWL , but 12,000 kg advertised should cover it


Pet hate of mine. I don't care for SWL, tell me what the MBS is and I will work out what's safe... ;)

Interesting the pre-made dyneema ones I could find were $100+, which does not make much sense given how much the parts cost (lazy tax much?)

Looks like I might be better off using lifting slings instead - as an example this 3m lifting sling for $30 or so http://www.ebay.com.au/itm/2-Tonne-3-Metre-Round-Lifting-Sling-Green-Polyester-Aus-Standards-/261050782291 (it is a bricks an mortar safety gear store in Australia, not a dodgy offshore backyard operation)

According to my calculations this gives a straight line MBS of (just over) 13T when used as an upside down basket - that is the same setup as a flat sling, but because my one is round it would be doubled over.

Or is my maths wrong? :confused: