Turnbuckles

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Ric

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My boat had six open-cage bronze turnbuckles. One seized solid on the stainless steel shroud swages so after a lot of elfin and blinding I had to skilfully kill it to death with a disc cutter, luckily without damaging the swage.

So now I will replace the little blighter and all its perfectly innocent hard-working brothers, and condemn the whole family to a long slow melt-down in the local land-fill site.

So what should I replace them with? Open-cage or closed? Bronze or Stainless? What is best magic-goo to prevent future seizures?
 
Ric said:
My boat had six open-cage bronze turnbuckles. One seized solid on the stainless steel shroud swages so after a lot of elfin and blinding I had to skilfully kill it to death with a disc cutter, luckily without damaging the swage.

So now I will replace the little blighter and all its perfectly innocent hard-working brothers, and condemn the whole family to a long slow melt-down in the local land-fill site.

So what should I replace them with? Open-cage or closed? Bronze or Stainless? What is best magic-goo to prevent future seizures?
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Never had a problem with bronze (chrome plated) and s/s screws, I have had good results with a moly-slip lubricant.
 
The bronze body - stainless endings turnbuckle is best there is.
But what you had problem with was threaded swaged endfitting.
It's often used as a way to save some little bit money, but this is wrong method of attaching the rigging :p
As there is no toggle between wire and turnbuckle the thread may bend slightly and there you have it. Or may be bent more then slightly and then you have no mast... Or if cold swaged - this is much pressure involved, so a thread quality may be bit compromised. Happens.
Just use normal turnbuckles with their original ends, jaws, (or however this is called in english), so you are sure the thread is proper.
Pity you cut one...
 
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Turnbuckles (rigging screws or turnscrews)

As said I think the bronze are best. I think the best way to deal with seizing is a regular (each winter) unscrew and grease (axle grease). This regime kept my closed bronze good for 32 years. I have recently replaced them simply because it seemed like a good idea. (not even sure now) Now with SS open body, I will continue to undo them every winter.
So IMHO just replace the broken one with same. good luck olewill
 
sarabande said:
galling is partly caused by minute metal particles grinding into the threads, so medical standard cleanliness when assembling.

Then use a standard anti-galling grease, not WD39 or any normal grease.
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I recently sailed with a Dutch guy (very capable sailor, IMHO) who uses WD40+Talcum Powder to stop threads seizing. I can't confirm the outcome, but I shall be trying it.
 
It's not possible for stainless / bronze turnbuckles to gall. They're usually one of the bits of kit on a boat that really are impervious to neglect.

Galling is only mechanically possible with stainless on stainless threads and molybdenum based 'never-siezes' (not copper based) are the only proven solution, and even that is not 100%.
 
TimBennet said:
Galling is only mechanically possible with stainless on stainless threads and molybdenum based 'never-siezes' (not copper based) are the only proven solution, and even that is not 100%.
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Why not copper based please? I've found Coppaslip (sp?) quite helpful, am I committing a metallurgical sin? Moly is horribly messy!
 
Reason for Bronze - stainless is the threads will not gall, but may stuck always for other reason. Any simple lubricant is advised for ANY PLACE some metal in rigging contacts another. Clear lubricant. Vaseline, lanoline, oil, clear grease (not 'getting sticky later white stuff' I found in UK marina stores, stay well off from such :D )
Silicone bronze is usually self-lubricating, but oil helps anyway.

BTW: lubricating the wire rope prolongs it's life a lot...
 
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With stainless on stainless the major problem is likely to be galling, which is a micro-welding mechanism. Any lubricant is likely to be better than none, but considerable research into the subject suggests that MoS2 based lubricants are the best option. Copper, another solid lubricant, may be pretty good also but liquids will tend to be lost from the contacts.
 
alahol2 said:
[PERNICKITY] Think I'm right in saying you turn a rigging screw anti-clockwise (looking from above) to tighten the rigging.[/PERNICKITY]
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Not always as it depends upon if you have RH or LH studs. That's why both RH and LH studs and toggles are made. On my present boat it happen to be anticlockwise from above to tighten.
 
Troubadour said:
Why not copper based please? I've found Coppaslip (sp?) quite helpful, am I committing a metallurgical sin? Moly is horribly messy!
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Selden supply a clear and very sticky turnbuckle oil in a little plastic bottle that works a treat. Daft price though, but if you can get hold of one of the synthetic gear oils like Shell TIVELA OIL S 320 it looks just like it and works just as well. Problem is unless you know someone with access to the 320 it is rather expensive.
 
Troubadour said:
Why not copper based please? I've found Copaslip (sp?) quite helpful, am I committing a metallurgical sin? Moly is horribly messy!
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No it's no metallurgical sin! But finding Copaslip 'helpful' may not be a scientifically provable solution to true stainless steel galling. It could well be that non of the fittings you have assembled with Copaslip would have galled even without it - galling doesn't happen 100% of the time!

So you could go years applying Copaslip to the assemblage, enjoying the smoother feel as you screw it up, being relieved it doesn't gall, and believing the Copaslip 'helped'.

However if you are a manufacturer of stainless steel components that are assembled with airtools using thousands of stainless fasteners every hour, you would be really concerned if any significant percentage of your components were ruined by galling. So there has been extensive research where the same bolting operation is repeated thousands of times and the percentage of galling incidents is noted with bare threads and lubricated threads (talc, oils, greases, Copaslip, Molybdenum disulfide, etc), and although they all helped to a degree, only the Neversiezes based on 70% pure molybdenum disulfide, were found to help significantly*. Fastorq Inc now have a new product they claim is even better, but I've never used it.

But you're right - they are messy! But when you're refitting large lead keels with built-in stainless steel bolts, the fear of one of them galling and ruining the whole casting keeps you awake at night.

* I believe this research was enough to get the scientist inducted into the American Fasteners Association Hall of Fame!
 
Molybdenum is nice and easy, at least the powder - some oils with it also available - but I heard it can be washed out (or was it something else) by detergents. So no washing the turnbuckles :)
But then - bronze and no problem.
 
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