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Thread: Snatch strap designed failure point?

  1. #1
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    Snatch strap designed failure point?

    Given the snatch strap and tow rope threads (and particularly reubsrover's side question), what would be the downside to a designed breaking point in the centre of a snatch strap? Where does a standard snatch strap fail if in good condition and loaded above breaking strain?

    While a central break point doesn't solve the problem of tow ball snatching, it does at least reduce the risk of tow point failure by limiting the load. If the strap breaks centrally it minimises the distance the tip can move (1/2 the length of the rope rather than the full length) but more importantly ensures that the lightest mass (i.e. lowest kinetic energy) section of the strap is in motion, pulled by the recoil of only 1/2 the strap. While I definitely wouldn't want to be slapped by one, it is less likely to be fatal than a steel (or brass) ball pulled by the full length of the strap at full stretch plus overload.

    As a side benefit, the break point would be the first place to inspect to see if the strap had been overloaded previously.
    Steve

    2003 Discovery 2a
    In better care:
    1992 Defender
    1963 Series IIa Ambulance
    1977 Series III Ex-Army
    1988 County V8
    1981 V8 Series 3 "Stage 1"
    REMLR No. 215

  2. #2
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    From a rigging point of view it is nearly impossible to build in a failure point with something like a snatch strap. If you could it would most likely be a one use only product.
    If you are likely to need a snatch strap or choose to use one it would be a good idea to get some purpose built recovery points installed on your vehicle.
    I know when im loading things up to a point that is likely to lead to a failure of a fitting i place a secondary preventer on the line, chain, wire that i am pulling with. I use a 1T sling 2-3M long attached to a point strong enough to take the kinetic energy out of the pulling line if the fitting fails.
    So on a car that would most likely be around the chassis and back onto the snatch strap eye even a decent length of 10mm rope can be used for this.

  3. #3
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    So, id=f a strap were designed with an extra 'eye' big enough for say a caribeener to go through which could be attached to the vehicles with say 10mm rope, it would be a lot safer?
    Can't be to hard surely? Or is this just too damn simple?
    D4 SDV6, a blank canvas

  4. #4
    Tombie Guest
    Some straps are available on the market with a "tail" which attaches to another point.

    Upon failure of the main eye or mount the strap is 'caught' by the secondary strap.

  5. #5
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    you wouldn't need a safety strap if the snatch was connected securely to a recovery point with everything rated higher than the snatch itself.

    If a failure point were designed into a strap, and it failed, there are people who would tie the two halves together with a knot which as a projectile is almost as dangerous as a tow ball.

    You won't find me on: faceplant; Scipe; Infragam; LumpedIn; ShapCnat or Twitting. I'm just not that interesting.

  6. #6
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    With regards to the original question - they generally go around the stitching/eye as it's the weakest part of the strap. What tends to happen then is pretty much the full length of the strap is free to flick around - hence why we always dictate 1 1/2 times the paid length for spectators.

    This end can be quite dangerous in itself, but imagine if 2 straps were connected together with a shackle - hence why that practice is discouraged so much.


    Cheers
    Chris

  7. #7
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    Quote Originally Posted by RR P38 View Post
    If you are likely to need a snatch strap or choose to use one it would be a good idea to get some purpose built recovery points installed on your vehicle.
    The tip re secondary restrainer is helpful. I guess something reasonably long would be required in the case of a snatch strap failure as the pulling vehicle is likely to still move a fair distance further and the strap recoil will shorten the length as well.

    The issue with the "purpose built recovery points" is that in the case of the too-common towball death, it is the other vehicle that you need to watch out for. To prevent MY death, I'm better to snatch off weak attachments, though I may kill someone and not get unbogged.

    Only accepting help from properly trained people with properly built vehicles is probably the key.
    Steve

    2003 Discovery 2a
    In better care:
    1992 Defender
    1963 Series IIa Ambulance
    1977 Series III Ex-Army
    1988 County V8
    1981 V8 Series 3 "Stage 1"
    REMLR No. 215

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