Considering eye thimbles and sleeves for standing rigging.

[cyrano138]

In his book, Nigel Calder seems to think the main problem with this system is that larger wire around a small bend radius is weakened, which I'm aware of, and that under load, cheap thimbles can deform, essentially leading to a de facto decrease in bend radius.

This, according to Calder, is more of a problem on wire over 1/4". My boat is a Cal 20, which uses 1/8".

I figure if I can offset the loss of strength by sizing up my rigging and using large, very heavy duty thimbles it should be no problem. My plan is to use 1x19 316 stainless wire and the heaviest thimbles I can find, preferably with a large bend radius (at least two inches if possible). Going from a 1/8" wire to a 5/32" wire nearly doubles the WLL and adds only 5 lbs of weight aloft.

In a perfect world I'd happily use sta-lok or something comparable, but the cost would increase by a factor of 10. I realize that for a lot of folks with sailboats questions about whether or not to spend money on a better, more expensive option are just that -- questions about whether or not to spend the money. I just don't have it to spend.

My question, having said all that, is, can anyone help me source the appropriately large and heavy duty thimbles? I can't tell from most sites what would be appropriate.

I appreciate any help and advice anyone can offer. Thanks!

[psk125]

You plan to use nicopress sleeves to secure your standing rigging? Does Nigel Calder actually recommend this? Have you discussed it with your insurance company? Their rate increase could offset any 'savings' you envisage from going this route. Is your rigging failing now?

[capt jgw]

Back in the'80's I built a 24 foot Bruce Roberts design. Standing rigging was 3/16" 1x19 wire and I used Nicopress fittings on all, two sleeves per end. Bending the 1x19 around the thimbles was a real pain and of I were to do it again I'd use 7x7 or 7x19. A little more stretch but much more flexible. I sailed that boat pretty hard and the rig held up just fine. I've used Nicopress for many things since, always use two sleeves, and never had a failure.

[HeywoodJ]

Our beach cat of similar length was rigged with thimbles and nicopress from the factory. Pretty much the same size, 1/8" 1x19. You're overthinking this, at that size the thimbles are pretty stout to begin with just because of manufacturing needs. I'd be happy with these, because the throat opening is almost non-existent.

And I wouldn't worry too much about the insurance man, on a 20' boat that is at least 35 years old the deductible, if insured, is probably more than the whole boat is worth.

[Bowdrie]

Up until they went out of business, the Wilcox-Crittenden outfit produced solid thimbles, (with suitable holes for rigging pins,) out of cast bronze.
However, the real deal was the bronze "poured socket" fittings for several wire sizes.
Those would be perfect for your job.
Actually, a poured socket has much to recommend it, reusable without any extra parts and easy DIY with little chance of failure.
I believe there are a couple of outfits that still make them.

[Nekton73]

If you upsize your rigging you will gain little in safety but surely impart higher tension to achieve a stable rig than your boat was designed for, thus stressing the hull and rigging terminations beyond their engineered purpose. Standard tension for a wire rope sailing rig is between 10%-20% of breaking strength, before any load is put on the rig from actually sailing. Take me at my word or doubt and research, up to you, but lots has been written (both good info and not) on this forum, and in books innumerable, about tensioning a rig and the forces on it as you sail with different wind strengths and sail combinations, so if you like rabbit holes...



1x19 stainless is not really meant to be bent around a thimble and nicopressed. You're better off with 7x7 or 7x19, but swaging stainless will of course require stainless thimbles and ovals, and a specifically calibrated swaging tool. If you go galvanized xips gac then you can use copper or aluminum ovals, and galvanized thimbles and it will be even cheaper than stainless but you will have increased corrosion concerns and dissimilar metals. Swaging your own terminations is dead easy with a bit of practice and. Swaging stainless is a bit different than copper or aluminum. The former relies on friction, the latter is a cold flow process that actually pushes the material of the oval into the gaps in the wire lay. Cut open a copper or aluminum swaged galvanized wire and you can see this clearly. Cut open a stainless swaged wire and you will see no cold flow.



As for strength reduction, not sure what your reference is but standard thimbles matched to wire diameter (with the correct D/d ratio, regardless of material) give 100% line strength when properly terminated. This means one (1) not two or three or seven ovals. One is enough. More ovals doesn't increase the strength or add any safety margin. Quality thimbles will not deform under load unless you significantly exceed the working load limit of the wire, at which point the deformation is an indicator that you have a problem you need to rectify. This is why visual inspections by a knowledgeable rigger are so valuable. Whether you trust their knowledge and advice (or mine) is another matter. Back to the design of your boat... you should not be exceeding the WLL of the recommended wire for your boat unless you experience extreme conditions, regular sailing just won't/shouldn't do that. If you are seeing deformation and damage under normal sailing conditions then something else is wrong. Upsizing your rigging does not help you here, it just transfers the stresses and loads to other areas of your boat that are harder to inspect and recognize the problem. If you're really worried about open thimbles, used a closed sailmakers thimble. If that deforms then you really should be worried. You'll have a wider throat angle at your swage, which will reduce strength a small amount, but this can be compensated for by placing the oval a bit farther from the apex of the thimble.



So after this long winded diatribe that didn't really answer your question, if you're looking for good quality thimbles for this project just buy them from a good quality manufacturer such as Ronstan, Seadog, Suncor, etc. I think Samson still makes a bombproof bronze thimble if you want to go that route. You don't need a heavy duty thimble that won't deform. You don't want a flimsy light duty one certainly, but a good quality thimble from a reputable manufacturer is all you need. If it deforms under load then it is telling you something... your rig (and wire rope) is being stressed beyond what it should be and you have other problems to solve.

[Ballsnall]

Originally Posted by Nekton73

If you upsize your rigging you will gain little in safety but surely impart higher tension to achieve a stable rig than your boat was designed for, thus stressing the hull and rigging terminations beyond their engineered purpose.

Baloney.

You are correct though, 1x19 is not suitable for use with thimbles. Change the wire construction and standard thimbles will be just fine.

Have you priced dyneema with lashings? Given the cost increase in stainless it may work out economical.

[Benz]

Suncor has supplied me with heavy-duty closed thimbles in the past.

[cyrano138]

I realy appreciate everyone weighing in. I was planning on using tinned copper sleeves if possible. Some sites seem to say the SS ones require a special (and probably pricier hydraulic press). Also, I could only find the sleeves 304.



To anyone who's used this method, including one of the posters above, did you use copper or SS sleeves? Did you ever switch out the 1x19 for one of the more flexible types?



Thank you for the recommendation on some thimble brands to look for also.

[capt jgw]

Originally Posted by cyrano138

I realy appreciate everyone weighing in. I was planning on using tinned copper sleeves if possible. Some sites seem to say the SS ones require a special (and probably pricier hydraulic press). Also, I could only find the sleeves 304.



To anyone who's used this method, including one of the posters above, did you use copper or SS sleeves? Did you ever switch out the 1x19 for one of the more flexible types?



Thank you for the recommendation on some thimble brands to look for also.

I used the copper sleeves and stayed with the 1x19 wire. Haven't done 1x19 since but have done 7x19. It was a lot easier. I see the hardware stores now have what appear to be aluminum sleeves. I've used them on some light duty things but I don't know if they're as strong as the copper. Never tried SS sleeves, I doubt my hand held press, the kind with two bolts you tighten down, could do them. It's hard enough with copper or aluminum.

[cyrano138]

Aluminum is definitely a no go, from what I can tell. I was planning on picking up one of the swaging tools that looks like a bolt cutter. I've used them before, I assume properly but who knows.



Thanks for the help.

[capt jgw]

Yea that's the one you want. I didn't have the bucks for it at the time so I bought the cheaper one. Got the job done but it wasn't easy. I had to lock the tool in a bench vice and use a cheater bar on the wrench.

[thinwater]

Cal 20? Don't have the proper swaging tool for SS?



I'm not a proponent of Dyneema for standing rigging in many cases, but this is one of those case where you should take the time to learn about it. I would do that before compromising with wire rigging terminators.

[cyrano138]

Originally Posted by capt jgw

Back in the'80's I built a 24 foot Bruce Roberts design. Standing rigging was 3/16" 1x19 wire and I used Nicopress fittings on all, two sleeves per end. Bending the 1x19 around the thimbles was a real pain and of I were to do it again I'd use 7x7 or 7x19. A little more stretch but much more flexible. I sailed that boat pretty hard and the rig held up just fine. I've used Nicopress for many things since, always use two sleeves, and never had a failure.

How heavy was that boat, approximately? The Cal 20 weighs about 2000 lbs. Just curious.

[cyrano138]

Originally Posted by thinwater

Cal 20? Don't have the proper swaging tool for SS?



I'm not a proponent of Dyneema for standing rigging in many cases, but this is one of those case where you should take the time to learn about it. I would do that before compromising with wire rigging terminators.

Unfortunately I'm on an even tighter budget with respect to time than I am financially. Maybe down the road. Thanks for weighing in