BOTTLESCREWS /TURNBUCKLES

If the wire is swaged to one end of the bottle screw that is probably a right hand thread - or at least it was on the forestay furling gear that I recently tightened. However, if its a stand alone bottle screw that could have been fitted either way up you will have to look at the thread or simply try turning it and see what happens.

I have found that "try it and see what happens" frequently answers boat related questions. It either works the way you want it to or it does not. A simple test that I discovered long before the internet came along.
Do you know if it is metric or imperial thread?
Not relevant unless you are trying to fit parts together from a box of boat jumble bits. Even then the "try it and see what happens" test will soon show which bits fit together without any further technical knowledge.
 
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Not relevant unless you are trying to fit parts together from a box of boat jumble bits. Even then the "try it and see what happens" test will soon show which bits fit together without any further technical knowledge.

Relevant because, according to the Jimmy Green website, imperial rigging screws are generally RH but metric are generally LH.
 
Around here the swaged on to wire thread is always RH which then makes the bottom toggle LH thread so looking down tighten is done by anti clockwise turn looking from above.
Now my sneaking suspicion is that OP has turnscrew that will not move either way. A common failing due to corrosion and galling. The answer is to remove the turnscrew if he can at least from the bottom. This may enable him to move either the LH thread part or RH thread part individually. If one or both will not move then heat or bashing between two hammers at thread part and various solvents may get it moving. If not then he is up for a new trurn screw. (or is it called turn buckle? or bottle screw?) Me I move and grease my 4 every winter. yes I have had them seize up. ol'will
 
Surely all bottlescrews have both a RH and a LH thread. Otherwise they wouldn't work.
The example they use is of a swaged fitting at one end so that you can copy your current stay correctly. Since most yachts seem to use a swaged stud at one end, I have assumed, rightly or wrongly, that the OP also has this. Ie. the description and information on the Jimmy Green site is of the top thread, not the bottom.
 
Preparing to drop mast today. Found it impossible to loosen the locknut on the forward shroud port turnbuckle and had to cheat and drive the pin out of the fork under rigging tension, (which probably isn’t very good for it) and then free the locknuts off in a bench vice. The attempts in situ hadn’t done the (apparently bronze, so I suppose relatively soft) top locknut much good.

Interestingly, several online sources say locknuts arent recommended for “critical applications” since they can overstrain the threads, and I’d guess that would be especially true if massively overtightened, as this one seemed to be. Thinking I might secure with wire when I put them back.2EB44C93-50C1-4398-A598-E1B858CFD459.jpeg
 
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At marina workshop, having new shroud s made up, (I was reusing the old turn buckles) I asked the rigger if the left hand threads are always on the same end? Fortunately for both of us because he was just about to swage RH ends on and all mine were LH. He had to order the correct ones in for me.
 
I am surprised that no one has come along with an accepted convention. I my opinion it is most logical to turn the bottle clockwise when viewed from above to tighten the stay as its the same way as you tighten a RH bolt. The worst thing is to have a mix on the same boat. Many years ago most bottle screws had the same fitting either end so you just fitted then all the same way up.

David MH
 
Upper forks have stainless steel split pins which I find unacceptably difficult to remove (ok on a car but there they are usually in a rigidly mounted fastner and arent ss)

I suppose I could replace with little split rings, or maybe I could terminate a lock wire there, 2 dead birds 1 stone stylee?

a610c2fa-0552-4d92-bd91-1b20c90eec3c-jpeg.209117
4E969A05-87A5-4DFB-83DA-82E6722D689B.jpeg

Copper wire ought to be compatible with bronze turnbuckles, can be cut with common hand tools and should be foragable as old electrical wire
 
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I am surprised that no one has come along with an accepted convention. I my opinion it is most logical to turn the bottle clockwise when viewed from above to tighten the stay as its the same way as you tighten a RH bolt. The worst thing is to have a mix on the same boat. Many years ago most bottle screws had the same fitting either end so you just fitted then all the same way up.

David MH
My AI says thats the normal convention. It gives this video as a source.

 
Upper forks have stainless steel split pins which I find unacceptably difficult to remove (ok on a car but there they are usually in a rigidly mounted fastner and arent ss)

I suppose I could replace with little split rings, or maybe I could terminate a lock wire there, 2 dead birds 1 stone stylee?

a610c2fa-0552-4d92-bd91-1b20c90eec3c-jpeg.209117
View attachment 209211

Copper wire ought to be compatible with bronze turnbuckles, can be cut with common hand tools and should be foragable as old electrical wire
I was surprised how good water-pump pliers are at dealing with that kind of split pin use.

I think that personally I would not dare terminate the lock wire in there instead of some other fastening case that wasn't up to the job. I'm sure there are alternatives to the split pin that are ok, though.
 
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