AT REST
Think about it for a moment, "D" and "Bow" shackles are designed to connect a sling /tow strap to a load, Bow shackles are designed to take 2 or more eyes of the sling in the bow, the pin which threads in to the Bow body attaches the shackle to the load (or to a crane hook). Now if you apply tension in a sideways or not directly ahead direction, the pin is canted sideways and jambs against the hole, the sling eyes slide around to the side of the shackle body and pull against the thread on the pin and in the body. As the shackle is designed to only be pulled from the centre directly ahead, then this sideways tension distorts the pin and the body of the shackle and would more than likely bend those would be (if they could be) excuses for mounting points. You ask why they manufacture these recovery points and sell them, well look at the construction, easy, simple and cheap to manufacture, that is the main criteria, profit above actual usefullness.Originally Posted by I Love My Landy!
Just out of interests sake, since this topic arose I've looked into many of the bow shackle recovery points that are being sold, and the vast majority of them have the pin mounted horizontally (like in the photo above). Seems strange that manufacturers will design them with such a flaw. I reckon most people (me included) would not be aware that bow shackles are not meant to be mounted horizontally.
Edward
You can buy recovery points that have the pin hole vertical, swivel type eye bolts, bolt on hooks. I have seen many correct type recovery points on the Dakar rally cars lately.
Just because someone (who BTW doesn't have to meet any Govt. safety regs. or standards) brings out a recovery point that goes against the laws of Physics doesn't make it right, there was a supplier/manufacturer advertising on this Forum horizontal pin hole recovery points, I sent him a number of emails asking the reasoning behind his design and if he had any recovery points with a vertical pin hole, guess what no replies after many emails. Use commonsense when buying recovery equipment, test a shackle in a horizontal recovery point, pull sideways on it and see what stresses are applied and think if this thing breaks do I want to be at the other end of the sling when it does, used properly a shackle will outlast you, bend it and it will eventually fail, most likely when you need it most, Regards Frank.
Master
Master
SupporterThanks jakeslouw.
I've been thinking about using jate rings on the rear of my 110, but I hear mixed reports about them. Apparently the British Army uses them (the original brand), however I do know of two Sydney Land Rover parts outlets who no longer sell them as they believed they were unsafe.
Edward
Master
TopicToaster
Tank,
I agree totally with what you have pointed out.
Perhaps fashion or minor inconvenience is the driver here.
Due to the way the chassis are designed it is easier to pass a fastener horizontally through the chassis rails and attach a plate or those jate rings so that the plates are verical and therefore any hole for a shackle ends up with its axis in the horizontal plane. Once this was done initially others just followed.
Even the eye bolts are often seen with the hole of the eye with the axis in the horizontal plane. There are some that swivel but most don't. Once againt the shackle hangs down from the horizontally orientated pin.
I'd say that somewhere in that rigging handbook there is going to be something that requires you to inspect your gear before use. As I said pehaps they get around the problem by replacing the shackles often?
At least the towbar neck/tounge has the hole in the correct plane for the use of a shackle.
AT REST
Slug, as far as inspecting a shackle goes, first see if the pin will unscrew or screw up with no binding, if the pin is hard to do up or undo then the body of the shackle is distorted and is on the way out. Check for heavy nicks/cuts in pin and body, small nicks can be filed off large deep nicks can be dangerous, mostly use commonsense, if it don't feel right don't use it, Regards Frank.
AT REST
I think most copied the Army vehicles like APC's, Tanks, etc., the lugs (Horizontal) found on these vehicles were designed for lifting the vehicle during construction or loading onto ships, trains etc. Regards Frank.
Fossicker
SubscriberTank,
While I agree completely with the side load issue you've pionted out, other than beaches most recoveries won't be straight ahead vertically either. Albeit to a lesser degree usually.
http://www.dap-inc.com/acc/acc-img/w...el-shackle.jpg
Anyone used these? Ive not seen them before, just a quick google search.
AT REST
Boof, not quite sure what you mean, if you mean winching/recovering on a steep slope, then usually both vehicles are at the same angle, unless one vehicle is over a vertical cliff face, am I reading your post right, if so rotating eye bolts solve all the problems, Regards Frank.
Wizard
Boof,
I've used the swivels you've posted before. I've attached a picture of the swivels built into a Scorpion Racing winch bumper. They are the same swivels minus the mounting block and they worked very well with a bridle. I had a couple occasions where I had to fetch mysel out using the winch and a snatch block back to the bridle. Their strength lies in the fact that they are mounted directly in line with the chassis and the bumper fixings.
On the rear I had 2 of the block swivels you posted with T braces welted onto backing plates and bolted to the main chassis rails (I didn't use their back block).
Long story short, if you can get them I can recommend them. Just remember to have a long hard think about spreading the load where you mount them.
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