Snailtrail Posted December 30, 2013 Share Posted December 30, 2013 Hi, I'm looking for an easy way of stopping safety bonds going walkies from fixtures. I've seen ones like this http://www.canford.co.uk/images/itemimages/600C/18-263_01.jpg And I'm looking for a sensible way of retrofitting a middle crimp or something like that, cable ties are a bit too easy to cut. I thought of a wire rope grip (dog grip) but that could be a bit messy. Anyone else got any cunning plans that work? Sam Link to comment Share on other sites More sharing options...
p.k.roberts Posted December 30, 2013 Share Posted December 30, 2013 How about steel cable ties rather than the usual nylon variety? Link to comment Share on other sites More sharing options...
J Pearce Posted December 30, 2013 Share Posted December 30, 2013 If your bonds are soft eye at one end then just thread that onto the yoke. Then the safety goes round bar and clips into the soft eye.If your bonds have hard eyes or clips at both ends that trick won't work sadly. Link to comment Share on other sites More sharing options...
top-cat Posted December 30, 2013 Share Posted December 30, 2013 Just use normal ferrules! It's not complicated... buy them in Flints. Copper ferrules and a crimping tool won't cost you much at all. Flints also do the Nicopress system which is very convenient, if you're feeling rich you could get a hydraulic crimper to eliminate the effort involved, or at least buy a bench-mounted crimping tool to reduce it by a lot. The small hand tools need quite a hard push. 2mm or 3mm SWR would be fine, it's very cheap to buy on a 100m reel, then a big bag of ferrules, and then you can also get the captive screw-gate carabiners like you've listed above. Making your own is very simple to do. Link to comment Share on other sites More sharing options...
Snailtrail Posted December 30, 2013 Author Share Posted December 30, 2013 Just use normal ferrules! It's not complicated... buy them in Flints. I could invest in that route but was looking for a neat way of retrofitting something to existing bonds if at all possible. Link to comment Share on other sites More sharing options...
top-cat Posted December 30, 2013 Share Posted December 30, 2013 Wire rope and ferrules are so cheap I'd be inclined to cut the carabiner part off, and start again. Link to comment Share on other sites More sharing options...
jonathanhill Posted December 30, 2013 Share Posted December 30, 2013 If you were to make your own safety bonds or modify pre-made ones, would you not need to re-certify them? The simplest way I have found is the one that Jon suggests, remove the yoke fixing on one side and thread the soft loop end over the yoke. You can afford to buy shorter bonds then. A 300mm bond would suffice. For the ones that you have linked to, a metal or nylon cable tie (be sure to cut the excess tie off as close to the mechanism as possible to avoid cutting fingers) sic urging a loop that is threaded round the yoke is about your only option. The cable tie should not form any part of fixing the cable tie to the light. Link to comment Share on other sites More sharing options...
top-cat Posted December 31, 2013 Share Posted December 31, 2013 If you were to make your own safety bonds or modify pre-made ones, would you not need to re-certify them? Certify them for what? From a legal standpoint, a safety bond doesn't require any more certification than hanging a TV on the wall. You, as a 'competent person', certify the equipment as suitable for the purpose in which it is used. Contrary to popular belief the rigging industry does not have these special 'certifier' elves who run around the warehouse stamping things. The SWL of the wire rope should be supplied by the supplier, and when using a system like nicropress, the manufacturer will advise on the effect on that SWL that using their ferrules has. That is perfectly enough to 'certify' them as fit for use. Frankly if you are using 2 or 3mm steel wire rope and securing it captive to a source 4 or a par can then you can be pretty sure that the safety bond will be perfectly adequate for the job! A lesser known fact with safety bonds is that when the bond is secured captive to the fixture, it doesn't need to have any weight rating printed on it, because by attaching it to the fixture in the first place you are stating that it is sufficient to hold the weight of said fixture. Only safety bonds which can be entirely removed from the fixture need marking in this manner. Link to comment Share on other sites More sharing options...
Seano Posted December 31, 2013 Share Posted December 31, 2013 Certify them for what? From a legal standpoint, a safety bond doesn't require any more certification than hanging a TV on the wall. You, as a 'competent person', certify the equipment as suitable for the purpose in which it is used. Not everyone in the market for a safety bond is competent to determine that a diy solution is fit for purpose. Nor is everyone who has access to a drum of SWR, a box of ferrules and a press. The SWL of the wire rope should be supplied by the supplier, and when using a system like nicropress, the manufacturer will advise on the effect on that SWL that using their ferrules has. That is perfectly enough to 'certify' them as fit for use. Frankly if you are using 2 or 3mm steel wire rope and securing it captive to a source 4 or a par can then you can be pretty sure that the safety bond will be perfectly adequate for the job! Case in point. It's not quite that simple. The SWL of a wire rope assembly tells you what you can safely suspend on it (subject to various conventions to be followed and decisions to be made regarding factor of safety). It does not tell you the weight of a fixture that can be dropped onto it from some unspecified height. "Pretty sure" is really not good enough. On the hand-wavey guesswork scale of statistical significance, I'd say it needs to be a couple of notches higher at "moderately certain" or above. That might require some kind of regime of testing and quality control, y'know, the kind of things a manufacturer should do before putting a product on the market. (Backed up with appropriate product liability insurance.) Many people who might physically be able to manufacture their own bonds would prefer not to, and that is a perfectly reasonable and sensible position to take. Link to comment Share on other sites More sharing options...
jonathanhill Posted December 31, 2013 Share Posted December 31, 2013 I, for one, would rather buy pre-made assemblies from a reputable supplier, than have the hassle of manufacturing my own, with the headache of liability as well as having to keep wire rope, ferrules, thimbles and snap hooks in stock. I have had requests at work for us to buy a Nicopress swager and a stock of bits. I have resisted because, apart from the cost of one, maybe two swaging tools and the stock of consumables that I would have to keep, it is just easier to call Rope Assemblies* and order what I need, that then comes quickly and with conformity certification, meaning that I do not have to worry about liability. I reckon that the cost of a simple Nicopress swager, wire rope and ferrules to be around £250, but you could probably do with a larger model to make the swaging process easier, this then pushes the cost to around £400. * other suppliers are out there, I am sure. Link to comment Share on other sites More sharing options...
top-cat Posted January 1, 2014 Share Posted January 1, 2014 I, for one, would rather buy pre-made assemblies from a reputable supplier, than have the hassle of manufacturing my own, with the headache of liability Liability? Really? If it's getting sued you're worried about. whatever it was that caused a lardy great C Clamp or half coupler to fail in the first place is probably what's going to get you sued, rather than where the safety bond got manufactured. The SWL of the wire rope should be supplied by the supplier, and when using a system like nicropress, the manufacturer will advise on the effect on that SWL that using their ferrules has. That is perfectly enough to 'certify' them as fit for use. Frankly if you are using 2 or 3mm steel wire rope and securing it captive to a source 4 or a par can then you can be pretty sure that the safety bond will be perfectly adequate for the job! Case in point. It's not quite that simple. The SWL of a wire rope assembly tells you what you can safely suspend on it (subject to various conventions to be followed and decisions to be made regarding factor of safety). It does not tell you the weight of a fixture that can be dropped onto it from some unspecified height. "Pretty sure" is really not good enough. On the hand-wavey guesswork scale of statistical significance, I'd say it needs to be a couple of notches higher at "moderately certain" or above. A source 4 26 degree weighs 7kg. Flints state the SWL of their 3mm steel core galv SWR is 108kg. If you knock that down to 75kg to account for the terminations, you would still have to drop the fixture a metre before you were in danger of overloading the steel. If this is the case then my suggestion would be that you are using safeties which are slightly too big. If you have the more average sag of about 50mm in your safety bond then you would be able to hang something a little more substantial safely. All things considered, using a 3mm SWR safety bond on source 4s and par cans... not going to be a problem. Link to comment Share on other sites More sharing options...
kgallen Posted January 1, 2014 Share Posted January 1, 2014 Am I missing something? Fold a ready-made bond around the yoke and crimp the ferrule around the two standing ends. Voila as per the OPs picture. Link to comment Share on other sites More sharing options...
top-cat Posted January 1, 2014 Share Posted January 1, 2014 Am I missing something? Fold a ready-made bond around the yoke and crimp the ferrule around the two standing ends. Voila as per the OPs picture. I think you may be missing that you can't get a ferrule over another ferrule, so you need to put the ferrule on before terminating one of the ends... Link to comment Share on other sites More sharing options...
kgallen Posted January 1, 2014 Share Posted January 1, 2014 Yes sorry I was assuming (possible misguidedly) that you could get open ferrules, since they are not taking any weight just securing the bond to the fixture (I was a bit slow on the edit of my previous post, realising I'd made that assumption!) Link to comment Share on other sites More sharing options...
top-cat Posted January 1, 2014 Share Posted January 1, 2014 The only hope you might have is forming a bight in the steel and sliding the ferrule over the bight. Obviously you'd need to use long bonds as this would occupy a fair bit of it. Link to comment Share on other sites More sharing options...
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