The Badger Posted February 27, 2011 Share Posted February 27, 2011 True, it's better for the rope to fail first. I can't say for what sort of rope holds what, I know that the rope on my winch can hold quite a bit. But even if you use a basic lifting strop, these are 1 tone (they are the purple one's in England), so I would assume that your recovery point would need to be at least double a 1 tone lifting strop. Ok, in my case, My 110 is about 2 / 3 tones, so even if you are not taking into consideration, angle weight force etc etc I would feel safe that my recovery points can hold the weight of the vehicle, and still then I would still not all hang it on one point, then you can always use a lighter weight rope / lifting strop and feel safe that the stop will fail first.. Sorry off topic a little, I would not buy that recovery point. Anyhow Quote Link to comment Share on other sites More sharing options...
Tris Cocks Posted February 27, 2011 Share Posted February 27, 2011 I think that all lifting stops have a 7:1 safety factor built in. Quote Link to comment Share on other sites More sharing options...
tonylr4x4 Posted February 28, 2011 Share Posted February 28, 2011 have they shut down or something, there website dont work anymore.? Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted February 28, 2011 Share Posted February 28, 2011 I believe so, yes.Look at the date of the original post Quote Link to comment Share on other sites More sharing options...
landroversforever Posted February 28, 2011 Share Posted February 28, 2011 Their website (and hopefully the poor workmanship) have been gone for a while. Quote Link to comment Share on other sites More sharing options...
Range Rover Blues Posted February 28, 2011 Share Posted February 28, 2011 Strong enough that the rope fails first. Better to have a rope flying in the air than a lump of metal on the end of the rope. Hell yes! I remember something about lifting strops having a 6:1 safety factor, if this applies to towing strops I'm not sure and though i had a mate who worked at a lifting gear company I'm not sure again how much of the recovery gear sold comlies with the relevant laws anyway, but yes I'd rather have the join in a strop give way, then the strop would loose energy as it unravelled and ran through the shackles. As a rule I really try to avoid having a shackle anywhere other than on the recovery point (such as on a bridle strop or joining 2 ropes/strops). Anyhoo, as a starting point if the winch can pull 9,000lb (ok, don't laugh) then I'd want the brackets to hold at least that, right? Quote Link to comment Share on other sites More sharing options...
nickwilliams Posted February 28, 2011 Share Posted February 28, 2011 This is in danger of being OT, but since it's a subject I know a bit about and others have touched on it, here goes... CE marked textile lifting slings generally have a safety factor (i.e. the multiple between the rated working load and the breaking load) of 7:1 when new. It's a certainty that they don't get any stronger with age or use. Strops used for winching or towing are not considered to be lifting gear (in the eyes of the law at least) so while they may be based on (and coloured using the same code as) properly CE marked lifting slings, there is no guarantee that they are as strong, if they don't come with a proper CE mark, test. cert and Declaration of Conformity etc. Nick. Quote Link to comment Share on other sites More sharing options...
Range Rover Blues Posted February 28, 2011 Share Posted February 28, 2011 Cool, thanks Nick. Quote Link to comment Share on other sites More sharing options...
leeds Posted March 1, 2011 Share Posted March 1, 2011 Lifting straps are made from polyester as they have 'minimal' stretch. Your seat belts are made from polyester. Would you want a stretchy seat belt in the event of an accident? Climbing slings/harnesses are made from nylon and they are 'stretchy' to absorb shock loads. Polyester Towing/lifting straps are not intended for snatch recoveries. They will generate higher shock loads due to small extensions Nylon recovery/snatch/kinetic straps are better for recoveries due to larger extensions Do NOT use shackles to join two ropes/straps together. If a strap/rope fail you have 1kg of metal shackle flying about. HTH Brendan Quote Link to comment Share on other sites More sharing options...
mad_pete Posted March 1, 2011 Share Posted March 1, 2011 Kryponite ? don't be silly adamantium is the thing you need. Quote Link to comment Share on other sites More sharing options...
Niamh Posted March 1, 2011 Share Posted March 1, 2011 Do NOT use shackles to join two ropes/straps together. If a strap/rope fail you have 1kg of metal shackle flying about. BTDTGTTS, or rather a large dent in the rear bumper of my old Disco! However I've not seen soft shackles with a SWL >3 tonne anywhere. Niamh Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted March 1, 2011 Share Posted March 1, 2011 As an example of safety factors, my H14 winch (14,000lbs pull / 6.35 tonnes) was used for lifting on a utility vehicle and the test stamp on the top rates it for 1.25 tonnes max lift. Quote Link to comment Share on other sites More sharing options...
nickwilliams Posted March 1, 2011 Share Posted March 1, 2011 Lifting straps are made from polyester as they have 'minimal' stretch. Your seat belts are made from polyester. Would you want a stretchy seat belt in the event of an accident? Climbing slings/harnesses are made from nylon and they are 'stretchy' to absorb shock loads. Polyester Towing/lifting straps are not intended for snatch recoveries. They will generate higher shock loads due to small extensions Nylon recovery/snatch/kinetic straps are better for recoveries due to larger extensions Do NOT use shackles to join two ropes/straps together. If a strap/rope fail you have 1kg of metal shackle flying about. HTH Brendan You are basically correct, but lifting straps are by no means exclusively made from polyester. EN 1492, the standard for lifting slings, permits them to be made from polyester, polyamide (nylon) or polypropylene. The stretch characteristics are more a function of the way the material is prepared than of the choice of material. Some applications require the chemical characteristics of the material to be carefully chosen. Nylon is very susceptible to damage from battery acid, for instance (so don't store your tow rope in the battery box!) Nick. Quote Link to comment Share on other sites More sharing options...
nickwilliams Posted March 1, 2011 Share Posted March 1, 2011 However I've not seen soft shackles with a SWL >3 tonne anywhere. Any two round slings, or slings with eyes in the end, can safely be joined without any hardware using a larks foot, but it's best to ensure they are pre-tightened as much as possible before trying to use two slings joined in this way for kinetic recovery since the friction in the joint may damage the surface of the sling if the joint is tightened too quickly. Nick. Quote Link to comment Share on other sites More sharing options...
leeds Posted March 1, 2011 Share Posted March 1, 2011 Nick, whilst you are probably correct on the range of materials the load extension characteristic of the final sling would be dependent on many different factors. This would range from the actual choice of basic material i.e. polyester, nylon 6, nylon 6-6, nylon 6-12 etc. The molecular weight of the chosen polymer. The amont of draw imposed on the polymer filament, the weave of the webbing etc etc. The apparent strength of the sling would depend on the test regime used which can give vastly different figures. Hence why most physical tests are done to international standards. All this though is basically of no relevance to this forum. Larks foots whilst they can be used to join two slings together it is not a recommended method of joining two slings together. Reasons being they will be a B to undo after a significant load is placed upon them and that they do not lie neatly upon themselves which can cause stress concentrations and hence an apparent lower strength. With slings with sewn in eyes thread the one eye of sling A through the eye of sling B. Then thread the second eye of sling A through its first eye and pull the webbing through. Do not tighten up Sling A completely on itself but insert something soft into the loop such as a fleece, roll up mat etc. This will prevent the sling A tightening up completely on itself under load. Have photos somewhere and a link to a video somewhere which will demonstrate what I mean more clearly. Brendan Quote Link to comment Share on other sites More sharing options...
JJB Serenity Posted March 1, 2011 Share Posted March 1, 2011 Kryponite ? don't be silly adamantium is the thing you need. I agree but I have trouble spelling it Quote Link to comment Share on other sites More sharing options...
will4x4 Posted March 1, 2011 Share Posted March 1, 2011 RDS are selling a challenge truck on ebay with their front arms and trailing arms...... front ones do look very weak Quote Link to comment Share on other sites More sharing options...
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