Closed or open turnbuckles?

pcatterall said:
for clarity I was questioning the safety of an open or closed turnbuckle without nuts or pins.
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Are not the two issues are intertwined? Coming undone is presumably the biggest risk to rigging screws.

Open, bronze, seized is the most 'idiot proof' solution.

My experience of lock nuts on rigging screws is not the same as Refueler's.
 
Praxinoscope said:
...the last thing you should do with an open turnbuckle is to insert something flat and strong enough to turn it, this will risk weakening the turnbuckle, they should be tightened using a spanner (adjustable is OK) on the outside flats of the turnbuckle...
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Yet many/most closed turn buckles are adjusted in exactly that way? My preference has always been for open ones - you can see what's happening inside - and my choice of weapon for adjustment - in the absence of a suitably sized open-end spanner coming to hand - is a motorcycle tyre lever.
 
Interesting thread - I replaced the open turnbuckles on my boat and was concerned when a professional rigger told me to insert split pins and bend at 90 degrees in line with the turnbuckle which means there is no split pin to catch. There are no locking nuts.
I was worried that this would not stop them coming undone but he assured me that when tensioned they wouldn't. I thought I would double check so I phoned Sta-Lok, the manufacturers of the turnbuckles and their technical department confirmed exactly what the rigger told me. To date they haven't moved.
 
davidpbo said:
Are we talking at cross purposes folks? The split pins I mentioned go through the end of the threads inside the open turnbuckle to provide an end stop. The locking nuts are on the outside of the turnbuckle top and bottom and used to lock the thread once the correct tension is set in the shrouds, forestay etc.
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Don't think so ... but I must say that post 26 by "coveman" has me a bit puzzled.
 
davidpbo said:
Are we talking at cross purposes folks? The split pins I mentioned go through the end of the threads inside the open turnbuckle to provide an end stop. The locking nuts are on the outside of the turnbuckle top and bottom and used to lock the thread once the correct tension is set in the shrouds, forestay etc.
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I don't think so - the pins in my turnbuckles are positioned as you describe, with no locking nuts. I was advised with very lengthy technical language from Sta- Lok that if the turnbuckles are under tension they will not come undone. Time will tell!
 
coveman said:
I don't think so - the pins in my turnbuckles are positioned as you describe, with no locking nuts. I was advised with very lengthy technical language from Sta- Lok that if the turnbuckles are under tension they will not come undone. Time will tell!
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Any turnbuckle that when tensioned - the stay is not held completely still .. will basically have stay unwind those turns over time and this will loosen the turnbuckle.
 
coveman said:
I don't think so - the pins in my turnbuckles are positioned as you describe, with no locking nuts. I was advised with very lengthy technical language from Sta- Lok that if the turnbuckles are under tension they will not come undone. Time will tell!
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Will not, or should not? IMHO lock nuts are a simple additional safety measure, I am not aware that they cause problems.

I would have thought there was a definite risk of the changing tension in a twisted wire causing the turnbuckle to loosen without them.
 
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coveman said:
I don't think so - the pins in my turnbuckles are positioned as you describe, with no locking nuts. I was advised with very lengthy technical language from Sta- Lok that if the turnbuckles are under tension they will not come undone. Time will tell!
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If I understand correctly, you have been advised to put split pins in, but bend the legs flush with the body of the rigging screw so nothing catches on them, rather than wrapping the legs round the body? If so, surely they will still stop the rigging screw undoing itself? Can't see a problem in this.

It would be very brave to have a completely unsecured body - it will loosen - hopefully you don't mean this?
 
Even more confused !! The turnbuckle must be stopped from turning/loosening by something! On an open turnbuckle this is usually something through the holes at the end of the threaded components split pin/welding wire whatever. By way of belt and braces I guess you could have nuts at the top and bottom of the turnbuckle as well.
With the closed turnbuckle you must use the nuts.
On my new mizzen rigging I will opt for closed with nuts.
 
Having looked at some open turnbuckles on yhe the Jimmy Green website, it would seem that my understanding was incorrect and that the split pins stop the turnbuckle turning and were not end stops. The ones I saw had no lock nuts. As someone who had a 23ft trailerable boat where the mast had to be rigged and de-rigged fairly often, as stated before I would rather have had open turnbuckles with an end stop split pin and lock nuts.
 
davidpbo said:
Having looked at some open turnbuckles on yhe the Jimmy Green website, it would seem that my understanding was incorrect and that the split pins stop the turnbuckle turning and were not end stops. The ones I saw had no lock nuts. As someone who had a 23ft trailerable boat where the mast had to be rigged and de-rigged fairly often, as stated before I would rather have had open turnbuckles with an end stop split pin and lock nuts.
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There is nothing stopping anyone adding nuts and TBH - having had nuts on all my boats ... I'm more than happy with them.

I know this is a 'feeble' excuse ... but anyone dropped a split pin overboard when working on rigging ?? I know I have. Nuts don't do that from turnbuckles ... ;)
 
Refueler said:
There is nothing stopping anyone adding nuts and TBH - having had nuts on all my boats ... I'm more than happy with them.

I know this is a 'feeble' excuse ... but anyone dropped a split pin overboard when working on rigging ?? I know I have. Nuts don't do that from turnbuckles ... ;)
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Ah so, yes several times, but I always have a full box of spare pins on board so not a disaster.
 
Pye_End said:
If I understand correctly, you have been advised to put split pins in, but bend the legs flush with the body of the rigging screw so nothing catches on them, rather than wrapping the legs round the body? If so, surely they will still stop the rigging screw undoing itself? Can't see a problem in this.

It would be very brave to have a completely unsecured body - it will loosen - hopefully you don't mean this?
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Yes, I was advised as you have outlined. I would certainly not have a completely unsecured body. My worry was that even with the split pins in I felt it was still possible for the turnbuckle to turn/loosen but as i said previously, both a professional rigger and the manufacturers - Stay- Lok - told me this would not occur under tension. I was given a lot of technical speak ( which I didn't understand!) about forces etc but the moral was that they would not undo.
As davidpbo suggests I would think nuts could do no harm as a back up.
 
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