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Thread: Recovery System Design HELP and the Weak Link

  1. #21
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    I'm a little surprised about that shackle issue FeatherWeightDriver?


    I think that the LRA Recovery Point is good too, it is 2 x 20mm steel zinc plated with two recovery hooks bolted to it. Does away with the shackle altogether. Can't seem to paste a photo for some reason? See link this is an earlier concept (scroll bottom) : Recovery Gear

  2. #22
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    Quote Originally Posted by FeatherWeightDriver View Post
    Nope - I can get the pin of at 4.7t shackle rotated to about 10 or 15 degrees and that's it.

    You need at least double the current sized opening to get the shackle in and rotated.
    What about a 3.2t 19mm pin Shackle?

  3. #23
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    Bow or "D" shackles CAN NOT be used in any other way than which they were designed for. Quote: "Bow shackles can be pulled on almost any which way so get them." as Dave wrongly points out.
    If you put a sideways pull on any shackle it will become the weakest point, you can turn the shackle around as you stated, but if you have 2 eyes of a strap on the pin of the shackle one eye will be on top of the other and unevenly loaded and could cause damage to the eyes (Friction), Regards Frank.

  4. #24
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    Quote Originally Posted by nismine01 View Post
    Why, when you have to pay for, carry then put it in place AND use your tow pin would you not just use your tow pin.

    The end of the snatch strap goes in the pin goes through and wallah!



    I have done that for years, I understand the dangers of pulling from the tow ball, perhaps this is just to give someone a feeling of 'right part to use'.

    Dunno.

    Mike
    If you have a tow hitch that is straight and doesn't have a drop below centre line remove the tow ball and fit a shackle in the hole, cheaper than shown, Regards Frank.

  5. #25
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    Frank,
    I totally agree with you about only using recovery points that allow shackles to be used the way were designed, and a lot of them it seems aren't designed that well, or can only cope with a straight line recovery.


    I was suggesting that for a recovery that is not in line or when you use a bridle the recovery point should be designed so that a bow shackle can be used the way its designed to be used ie the bow at the fitting and the pin at the loop.


    Haven't ever considered having two loops in one shackle and one damaging the other, makes sense, but when would you ever be doing that?


    Having seen the new Landcruiser ARB Recovery point above it does have a slot that allows the shackle to be used the way its designed and is 20mm thick plate. I think that it is designed as a one plate system (and not two plates and a bridle as we've been discussing) but I'd have to check with ARB.


    As a result of your insight and as there don't appear to be any suitable recovery points for a D2 I'm going to ditch the shackle idea altogether. I've seen a set of Recovery Points made by Les Richmond Automotive for a D1 and D2. It is a 2 point system, also made from 20mm plate and eliminates the need for shackles. It uses those recovery hooks which bolt to the steel plates see a Hilux one that will give you the idea:
    Attached Images Attached Images

  6. #26
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    I particularly like the way that the centre of the hook lines up with the centre of the chassis rail, good design!


    This is a couple of photos from Les Richards site its a little difficult to see from the photos but I think its the best recovery point for a D2 that I've found:

  7. #27
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    Hooks are good, no shackles even better, only downside is hooks are back from the front and if bogged some digging maybe required to get strap eye on hook. If line of pull is above height of hook, in other words if tow vehicle is higher than the towed then you may need protective packing for strap where it contacts bottom of bull bar, Regards Frank.

  8. #28
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    Quote Originally Posted by Islandnomad View Post
    Frank,
    I totally agree with you about only using recovery points that allow shackles to be used the way were designed, and a lot of them it seems aren't designed that well, or can only cope with a straight line recovery.


    I was suggesting that for a recovery that is not in line or when you use a bridle the recovery point should be designed so that a bow shackle can be used the way its designed to be used ie the bow at the fitting and the pin at the loop.


    Haven't ever considered having two loops in one shackle and one damaging the other, makes sense, but when would you ever be doing that?


    Having seen the new Landcruiser ARB Recovery point above it does have a slot that allows the shackle to be used the way its designed and is 20mm thick plate. I think that it is designed as a one plate system (and not two plates and a bridle as we've been discussing) but I'd have to check with ARB.


    As a result of your insight and as there don't appear to be any suitable recovery points for a D2 I'm going to ditch the shackle idea altogether. I've seen a set of Recovery Points made by Les Richmond Automotive for a D1 and D2. It is a 2 point system, also made from 20mm plate and eliminates the need for shackles. It uses those recovery hooks which bolt to the steel plates see a Hilux one that will give you the idea:
    I am not sure I am reading you right, but a shackle whether Bow or D shaped are designed to carry the slings (eyes) in the D or Bow section, the shackle pin is designed to be on the hook or recovery point, you will notice that ALL RATED shackles have a larger diameter pin than the body of the shackle, shackles with same size or smaller pins than the body are NOT rated and should not be used for recovery or lifting, Regards Frank.

  9. #29
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    Really, why you can't have the bow or D against the recovery point? That's how ARB have designed their new Landcruiser Recovery Point see above, a big slot so that you can put the shackle in it and turn it around. I wouldn't have thought it would be an issue?

  10. #30
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    Quote Originally Posted by Islandnomad View Post
    Really, why you can't have the bow or D against the recovery point? That's how ARB have designed their new Landcruiser Recovery Point see above, a big slot so that you can put the shackle in it and turn it around. I wouldn't have thought it would be an issue?
    Sure you can do it that way, but eventually the sharp edges of the recovery point hole are going to damage the round section of the shackles' body with nicks and gouges, which can lead to stress fractures. Bow shackles are designed to accommodate more than one strap/sling eye, D shackles are designed to carry one strap/sling eye in the body of the shackle.
    If you stack strap/sling eyes on top of one another in the confined space of the shackle pin you will damage the slings/strap eyes unnecessarily, if you are going only ever use one eye on the shackle the use a D shackle, if more than one eye use a bow shackle, Regards Frank.

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