Checking out rigging screws

zoidberg

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Inspired - or perhaps detered - by another thread ( replace-rigging-screws-or-not.541884 ) I'm wondering what can usefully be done with rigging screws I've replaced with new.

As part of a 'project-refurb' and to placate the suspicious minds of insurers ( and the suspiciouser minds of loss adjusters ), I've bought all-new rigging and all-new rig'screws..... whether they were truly needed or not. I know the standing rigging was up and in use for less than ~2000nm before I acquired the boat, and it has 'languished' in my boatbits shed since. Others may well have done similar.

I'll certainly keep a couple of the stays, as emergency spares, and am thinking to do the same with some of the rig'screws. The question is that of how best to make a close inspection.

I'm aware of the principle of dye penetrant inspection. The materials are available online. What can the team suggest in terms of whether this could be used effectively by a ould daydreamer like misulf, to sift out the 'questionable' from the 'tip-top'?
 
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D

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On the rigs we have used ultrasonic cleaners on some parts that have been caked in dirt. Once the dirt is cleaned as normal the U/S bath gets the crud out of the tight spaces and allows better NDT testing. U/S cleaners are available low cost for DIY use these days e.g. from Machine Mart. Alternatively, clean the surfaces with a degreaser that evaporates easily. Good video on die pen: -

 
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vyv_cox

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It is not difficult to use but I question whether for rigging screws it would tell you much that a good visual inspection with a x10 glass would not. If you spotted a feature that you could not explain it might then be worth trying dye pen. Visual is good for small items that you can handle.
 

zoidberg

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Thank you again, VC.

You're 'worth your salt', as the ould Romans used to say before they started 'dissing' the Christians.
 

geem

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I check my rig with a magnifying glass and a kitchen sponge, the ones with a green scrubby pad on one side. Any dirt or staining on the wires, swages or bottlescrews can be cleaned off so you can check for cracks. One point worth mentioning is that if you find any dark brown corrosion stains anywhere, pay particular attention. They are normally a sign that something bad is going on. Clean this off with the scrubby and have a really good look with the magnifying glass.
It can be tricky to inspect bottlescrews properly without lying on the deck and then its not easy to see all the way around. I replaced my bottlescrews last year after finding a crack in one. Once I got them all off and had a really good look two more were cracked that I had failed to spot because off the way they were orientated. I replaced all of them as they were old, on the basis that if one was cracked then how long before the others developed a similar fault. In reality the cracking was probably age related failure and I should have replaced them earlier especially as we have done a lot of miles in the last few years.
I count a regular rig inspection as one of the most important aspects of keeping my boat safe. If I had left the rig inspection any longer I could have lost the mast
A Dehler 35 is now moored next to us here in Horta with no mast. Tough conditions last two days here so boats will have been getting a pasting on approach. Gusting 37kts on our instruments yesterday afternoon and been gusting of 30 constantly for last two days. The conditions for any boats onroute from the Caribbean at the moment are not good and dont look good for the foreseeable future
 

vyv_cox

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I wrote a piece on crack detection for PBO a few years ago. I owned several items with visible cracks but of course it was difficult for me to happen upon something thought to be sound but actually cracked. One of the items I did have was a propeller with three sets of cracks in the hub between all blades. Although the larger crack at the left shown in the pic was visible by eye I had not seen the fine one revealed by the dye penetrant.
 
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