Turnbuckles; split pins or locknuts?

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pcatterall

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My brain is on the blink! I couldnt understand why on my 'new boat' there was loads of insulation tape around the turnbuckles, looking closer and realised that it was to protect against damage by the split pins, then realised( at last) that previously I had used locknuts.
I can't see any advantage in using split pins and several disadvantages. Before I rush out and buy loads of nuts is there anything I have not considered?
 
Typically lock nuts are used on closed body turnbuckles and split pins or rings on open body turnbuckles.
I've never seen locknuts on open body turnbuckles, but this doesn't mean it isn't done.
On closed body turnbuckles I've seen them moused through the centre hole to back up the lock nuts.
 
Locknuts on their own can come undone. Only ever had one come undone though.
Best practice is to wire those with locknuts but no provision for pins.


Will you be able to get the left handed nuts at a sensible price?
 
An alternative is to use monel seizing wire of the correct guage. There is an advantage in that with care you can bend the twisted end neatly inside the turnbuckle, eliminating the need for tape.
 
On open body turnbuckles a continuous split ring ( like yer keyring) can be used through the splitpin hole of the threaded part and around one shoulder of the turnbuckle itself. No sharp projections.
Chandlery will have em at..a price
 
if there is lots of tape around the turnbuckle, make sure that any trapped water can escape, otherwise you risk a source of corrosion.
 
I have open, bronze, turnbuckles and have found the split "keyring" things tricky to put in place and oddly unreliable, I once found one on deck for no reason that I could work out. As you say, split pins have their drawbacks.
Last time I sorted out the rigging I put small bolts through the holes and held them with nylock nuts. I guess the thread size is 2.5 or 3mm, they are pretty cheap from your local stainless shop.
Suitably cut to length and well finished they do not snag sails or cut legs and can be reused.
 
I've had a couple of lock nuts come undone. One was on a Sonata in the middle of the North Sea in a strong wind. Had to crawl along the deck to put it all back together, with white water everywhere. Never again. Always open bodied for me now.
 
I had split pins but was castigated roundly by my wife when her new pair of trousers were torn when snagged on the exposed split pin. I don't use split pins now - I've fitted a 'shroud' of transparent braided PVC hose over each turnbuckle. Easy to lift up for inspection and no chance of fouling. The tops are cut with 'vees' and tied to the wire with whipping twine. Works very well.
 
I'm a great fan of the split rings. Trick is to use cutters and chop out about 8 -10 mm off one leg so the ring can settle with only one wire through the hole.
I find the best way to fit is to "wind on" round one leg of the open body screw and then run through the hole and body. Good idea is to place them on the side away from genoa sheets etc, so usually inboard.
Big advantages as far as I'm concerned are
They don't fall out.
Highly visible.
Don't cut clothing / sails.
Avoidsthe temptation to reuse (split pins) if you adjust your rigging.
Only one per rigging screw.
You can re-use.
Should also add that I use the same rings on the pins that hold the spreaders into the mast castings.
 
The only rig failure I've ever had was due to a split ring, so I'm a bit wary of them. I suppose with adequate precautions they have certain advantages. In my case, I think the genoa sheet was able to rub against the ring and rotate it out of position.

Quite scary how much a Wayfarer mast will bend when are hard on the wind with full sail in a F5!
 
Thanks to all for that! So nuts is out! I just noticed that one of my fittings has the split pin bent 'up and down' so it doesn't protrude beyond the turn buckle. It can't turn as the round end prevents this. Is this not an option?
 
On my old boat I used to have some little clips that looked like a C with a pin through the middle. I can't remember what they were called but they were fantastic - the pin went through the hole in the screw and the C part clipped around the body of the bottlescrew. A couple of turns of insulating tape around the lot to make sure nothing flicked them out and they were solid and secure.
Reusable and solid. Purpose made for the job, and I wouldn't hesitate to use them again, assuming I could find suitable ones for the bottlescrews I had.
 
The standard practice on aircraft control surfaces ( which people get rather upset about if they go wrong ) is to use 'castellated' nuts, if necessary drilled through and secured with monel wire-locking, against the 'undo' direction of rotation, not always right handed.
 
They serve different purposes. The split pin stops the turnbuckle coming completely undone, but the locknut holds the correct adjustment. My turnbuckes have both.
 
VicS said:
Why not just use a high strength Loctite thread locking fluid ?


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Click to expand...

Makes adjustment unnecessarily difficult.
If you tap the hole in the threaded bits of rigging screw M4, you can use nlyocs easily as locknuts on machine screws.

Any splitpin/wire/ring malarkey needs to be taped, or covered with tube.
Sheets have a great way of pulling them about, and people grab the rigging more often than you would expect!
 
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