CLASSIC YACHT RIGGING

[sgunns]

Dear Sirs,

I am restoring a 60 ft 1924 Nicholson ketch in Australia. We have cast new chainplates and have new bronze turnbuckles and toggles. I plan 316 1x19 s/s wire rigging with sizes ranging between 10 mm (3/8 inch) and 22mm (7/8 inch bobstay). My query relates to the wire terminal. I would prefer some form of bronze fitting.

I have seen a bronze terminal in which the ends of wire are fed through the fitting, spread and bent over, and then the bronze ferule is filled with lead or epoxy. Does anyone know who supplies such fittings, and how reliable they are, especially on larger wires?

Any other bronze ideas, noting I only want to use gal wire?

Steve

[Hwyl]

Mike posts on here. I don't think he has your fittings but he'll point you in the right direction. http://www.woodenboatfittings.com.au/

I can't understand from your post whether you have stainless or galvanised.

[George.]

I recently saw a terminal like the one you describe, for 5/8" wire. It was steel, not bronze, and home made - a sort of inverted cup with a 5/8" hole in the bottom. The wire was fed through, opened up, and had the ends bent, and the whole thing was filled with molten tin. The boat just returned from a trip from Brazil to Spain and back, so it appears to work.

I suppose you could cast a similar fitting out of bronze. Make the walls plenty thick, just in case there are imperfections in the casting process.

[Don Kurylko]

http://www.porttownsendfoundry.com/home.htm

[Ed Burnett]

22mm wire bobstay! That's rather large (around 29000 kg breaking load). Can your bowsprit deal with that sort of compression? Bearing in mind your rig configuration it strikes me that there are some numbers there that need to be checked again.

[PeterSibley]

Could that have been zinc ,George? It would also be compatible with most bronzes...alloys like manganese bronze,very strong and horrible to work

[ 01-12-2006, 04:38 AM: Message edited by: PeterSibley ]

[George.]

Could be zinc... the man was a Castillian trying to speak Portuguese... and the topic came up at the end of a late-night caipirinha session at a peaceful anchorage on Ilha Grande...

[rich morpurgo]

the bobstay on my boat has the highest load of any on my boat. at times 10,000 lbs on a 32 foot boat.

I can imagine a 60 ft boat could have that load. Plus a built in safety factor for a stay that get's a salt water bath every wave.

Rich Morpurgo

[Ed Burnett]

It's not uncommon for the bobstay to have more load than anything else and generous safety factors are also quite in order, but 22mm wire for the boat / rig in question really is pretty big.

Having components comfortably over-engineered is all well and good, but there comes a point where it starts to get very heavy, clumsy and inordinately expensive. Steve has already enquired about finding bronze rigging screws for 16mm wire (1" pin), finding the 1 1/4" pin stuff for 22mm wire is not going to be easy.

Engineering of this sort is not always as exact as we would like it to be. With any calculation one must always be able to take a step back, have a look at the numbers and sizes that have resulted and ask if they are more or less in line with what would be expected. I don't know enough about this particular boat to say the sums are "wrong" in this case, it just stikes me that this is big wire and I would personally be having a look back through the starting assumptions to see if they are in fact reasonable and realistic.

[Jay Greer]

I once lost a mast due to a poured zink terminal failing.
Never have used one since. If you have the time and the cahones then splicing is one way to go. If splicing is not your bag, then serving the wire with marlin or sein twine for several feet up and then turning it around a solid thimble and seizing with anealed stainless wire
is a solution. At least three or more seizings should be used. The wire end can be capped with a spent cartridge. This is a very traditional way to go and does not weaken the wire.
JG

[ 01-13-2006, 02:32 PM: Message edited by: Jay Greer ]

[George.]

The Flemish eye is quite easy to splice. Dalia's galvanized, fully wormed, parcelled, and served shrouds have Flemish eyes, finished with two SS wire seizings - one around the end of the splice, duly served over, and one just below it, seizing the two legs of the wire together as if there were no Flemish eye. Takes no more than half a day each, for a clueless amateur like me, guided by Brion Toss's bible.

So far, her masts are still standing.

[PeterSibley]

George ...if you get a chance do you think you could post a photo?

[sgunns]

Gents,
A few comments. Firstly the rig was designed by Gerard Dijkstra in Holland, whose credentials are about the best there are in classic yachts. I also queried the sizing with a local naval architect who checked and said he thought the sizes were right. The bowsprit tapers from 150 to 125 mm, 6 to 5 inches.

I looked on the Port Townsend web site and could not see the "bronze socket" type fittings.

One person suggested turning the wire over a thimble, and that was my first plan. However I have been informed by numerous people that 316 1x19 stainless will not bend around a thimble. For all the bronze authenticity, I still want to use 316 1x19 wire, so I seem to be stuck!

I will now try and find what s/s wire will bend around a thimble, and check strengths>

Steve

[FSS172]

Is this what you're looking for?

Swageless fork

[Ed Burnett]

Steve,

Re. the numbers, fine.

As for the terminals, for these wire sizes in 1 x 19 stainless I can think of three realistic alternatives:

1. Swageless terminals: Eg. Sta-Lok http://www.stalok.com/parts.asp
Not cheap, and only in stainless, but easy to assemble on the job. You can take apart and re-use the casings but need a new cone for each assembly.

Norseman are an alternative make using a similar system, as are the jobs that 3Si do as posted above.

2. Roll swages. (same link as above but go to "Swage terminals" in the drop down menu box.
Probably most cost effective, and still stainless, but not bulky so perhaps the least intrusive. Not all riggers will have the machinery to handle the sizes you are into.

3. Poured sockets. These are the jobs you originally asked for and can be had in bronze. I'm sorry I can't find a link to any pictures or suppliers on the web. The best I have is a couple of pictures in a ten (or more) year old catalogue from these people: http://www.newfoundmetals.com/catalog/pg01.html but there is no mention of wire terminals on that site.

These terminals tend to look a little bulky, but are well regarded as being very reliable. I recall someone once claiming they were one of the very few (perhaps the only) approved way of terminating lift (elevator) cables and such the like and this may be a way to start a search. In times gone by they were filled with molten zinc, I think now some kind of resin is used.

[George.]

Found a couple of photos. Was going to post them, but:

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[Ed Burnett]

Here you go: http://www.dibbleetools.com/catalog/index.php3?page=92

Not bronze, but that's the sort of thing.

Known as "Spelter sockets" it would seem. From the table it looks like you can get them to fit up to 4" diameter wire - the fork terminal for this weighs 783lbs!

[Andrew Craig-Bennett]

Spelter sockets are in regular use in the offshore towage business. I did not say "everyday use" because pouring the spelter socket for a big tow wire is a serious business and can take all day.

I have a 6" diameter bowsprit on a 37ft cutter. I most certainly don't have a 22mm bobstay!

[Don Kurylko]

http://www.porttownsendfoundry.com/id62.htm You will find the bronze sockets on this page of the PTF website. I think they are about $100 US each, possibly a bit more.

Cheers,
Don

[George.]

Finally got those picture, Peter.



Here is a seizing being made. Note that the first seizing - the one that goes around the end of the Flemish eye - is already made and served over. The one being made seizes the two legs of wire together outside the serving.



A just-finished eye splice. All that's left to do is trim the leather.

The Flemish eye is quite easy to do with 7-strand wire, and can be done around a thimble to us with rigging screws. Basically, you just separate three strands from the other four, lay them over each other forming the eye, and re-lay them. If you saw a drawing, you would have no problem - takes only a couple of minutes. But it is important to seize the ends, because otherwise it could slip under load.

[PeterSibley]

Thanks for the photo George....another reason to buy Toss' book.I very much like things I can do myself and preferably without a machine shop.

[Shaver]

Great photos, does my old heart good. I've been a rigger for 25 years and used many fittings of the above types in the mining sector in Australia both on and off shore. The swage less are fine for small stuff but without a doubt the best is epoxy filled as long as you clean the wires with thinners etc before adding the epoxy this is essential. the advantage is of course no corrosion. splicing is an option but splicing wire rope is a bloody pain. I have never tried pouring molten lead/zinc etc but have used them with no probs

[ahp]

A reliable way is to terminate your shrouds and stays with eye splices around rigging thimbles. Then serve the wire eye splice. Splicing wire rope takes a little practice, but its a worthwhile skill.

[PeterSibley]

While searching for a few diagrams of wire splices I found this...the "Boys Book of Seamanship and Gunnery", this is the rigging/rope page [img]smile.gif[/img]

http://www.pbenyon.plus.com/B_S_M/Th...struction.html

[sgunns]

Gentlemen,

I had an off-air reply suggesting that I should have more respect for Ed Burnett. I did not know who Ed was, (and he could have been the local drunk), but have now emailed direct and hope to engage him to advise on the project.

For the wire terminals, I have been involved with dozens of emails, numerous phone calls and the net is, that I can't find something in bronze. Even if I found an epoxy-filled socket in bronze, it appears the hole would not match the toggle pin. Build custom bronze sockets? Just too hard.

For those who recommended Port Townsend Foundry, I have sent about 10 emails over the past year including recently, and have never received a response. I wouldn't bother with them!

However, the conclusion has been reached with Ed that I was trying too hard. I will now use a Stalok stainless rolled swage terminal (as I had already bought them), and fit that to the bronze toggle.

Thanks for your time and input.
Steve