T.R | Title | User | Personal Name | Date | Lines |
---|
979.1 | | MILVAX::HO | | Mon Sep 12 1988 18:55 | 37 |
| The upper and lower shrouds on my 19 year old boat are the original
and don't show any apparent corrosion. Backstay, forestay, and
all wire halyards, lifts, and guys have been replaced at least once.
In the case of the main and jib halyards, replacement has been every
few years due primarily to damage from handling. Never had a problem
with any swaged fitting except the cost of replacing it (lots $$$)
when some other part of the stay went.
I've seen galvanized wire used only on halyards. The theory is
that stainless colds works and stiffens and will eventually fracture
at the most inoppurtune time. Galvanized isn't supposed to do that.
Galvanized is also cheaper which can be a consideration even on
a small boat if the halyard is going break from other causes anyway.
On a larger boat with lots of standing rigging the economics pretty
much dictate galvanized. With larger sized wire, splices rather
than swages are used. These are labor intensive and require stringent
manintenance. I was present at the launching of a newly built
traditionally designed wooden boat last year. Three big bronze
turnbuckles on each side attached to swaged SS wire held the mast
up. Deadeyes might have been more appropiate but the owner was
more interested in having the mast stay where he put it.
The epoxy and insert type of fittings are amenable to DIY but I
don't know if they're any more resistant to corrosion. They're
not cheap. They maybe useful to have on board as a repair item.
But it will be necessary to carry some extra wire too. If a swaging
breaks, the wire it's on will be too short to reattach. It'll be
necessary to replace the whole wire. One trick for fixing broken
wire I've read about, but never tried, is to tie a knot in it and
extend it with whatever line is available. This is supposed to
work even on 1x19 standing rigging. But after it's tensioned, the
knots is in forever.
I sailed one time on boat with galvanized halyards. The rust does
get all over your hands and eventually clothing and sails as well.
|
979.2 | Hand Splicing is worth a look | RAINBO::BURR | | Thu Sep 15 1988 18:58 | 21 |
| My very traditional teak ketch has stainless 1x19 wire shrouds and
stays attached to bronze turnbuckles. All of the joints are hand
spliced over cast bronze thimbals, then parceled with stainless wire
and finally served with tared marlin. The rigging was done before
I got the boat and is now about 8 years old. Everything is still
perfect, showing no signs at all of wear or deterioration. Every
year I remove 3-6 servings and check out the condition of the splices
and check to make sure nothing has started to fracture or corrode.
I then re-serve the splices I inspected and re-tar all splices.
(the tar smells great).
My understanding is that this (being very labor intensive) is by
far the most expensive rigging method to have done. However, it
is a method which anyone, given strong hands, patience, a good pair
of gloves and a rigging vice can do themselves. From what I hear,
hand splicing, if done right, is the strongest splicing method
available and is also the most flexible (the splices can take a
lot more bending close to the splice than a swaged fitting). I
know that my rig is enormously strong, is relatively maintenance
free and looks good too. Why not look into it?
|
979.3 | I'd use Sta-Lok fittings | MSCSSE::BERENS | Alan Berens | Mon Sep 19 1988 13:55 | 8 |
| Sta-Lok and Norseman fittings (all mechanical) are easily installed (all
you need is two wrenches and a sharp hacksaw) and are stronger than the
stainless steel wire. And they are reusable except for the inner cone.
Cost is perhaps a bit more than a swage (when you get them at a
discount) but they are reported to be considerably more reliable.
Essentially no maintenance either. I used Sta-Loks to replace the swaged
forestay and intermediate backstays fittings on my boat.
|
979.4 | more questions | LEODLN::BAHLIN | | Tue Sep 20 1988 10:11 | 23 |
| re: all
Thanks for the replies. I have a few comments and (as always) more
questions. My surveyor suggested hand splicing as the best choice
for terminations. In a rope splice I think you end up with 90-95%
of the original breaking strength. I've never seen a number for
wire though. Anybody have one?
Most of my rigging is 7x19 3/8" stainless. The prices for just
one end of this size wire are astounding. Sta-locks are $45.00,
turnbuckles are about $80.00, and toggles are in the $20.00 area
if memory serves me. Does anyone have a good source for this kind
of hardware.
I think I will let the compression sleeves go until they show more
signs of wear than they do now. Then as they look bad I will go
to a splice on the existing wire and use extension forks to get
the proper length back. Is this a decent strategy or is it more
sensible to chuck the whole wire when any part of it looks suspicious?
A final question.... Any comparisons on the relative price of
galvanized versus stainless wire?
|
979.5 | more ideas | MSCSSE::BERENS | Alan Berens | Tue Sep 20 1988 13:02 | 33 |
| Defender Marine claims to have the lowest prices on Sta-Lok fittings,
Merriman bronze turnbuckles, etc. Their service is poor (to be kind).
Another traditonal alternative is bronze socket fittings into which
molten zinc is poured around the wire. Once the zinc hardens, the
fitting is supposed to be stronger than the wire. Since these things are
used for elevator cables, they are probably quite reliable. New Found
Metals in Seattle is a supplier (see any issue of Wooden Boat for an
advertisement). As I recall, the fittings are not terrible expensive.
Certainly faster and easier than splicing (and cheaper if you have to
pay someone to do the splicing).
By the way, are you sure your rigging is 7x19? Most standing rigging is
1x19. 7x19 is used for running rigging (more flexible but somewhat less
expensive than 1x19). By the way, the breaking strength of 3/8" 1x19
wire is about 17500 pounds, and the breaking strength of 3/8" 7x19 is
around 12000 pounds, which is slightly less than the breaking strength
of 5/16" 1x19 wire. If your rigging really is 7x19, you could change to
5/16" 1x19 and perhaps save considerable money.
>>> I think I will let the compression sleeves go until they show more
>>> signs of wear than they do now. Then as they look bad I will go
>>> to a splice on the existing wire and use extension forks to get
>>> the proper length back. Is this a decent strategy or is it more
>>> sensible to chuck the whole wire when any part of it looks suspicious?
Trouble is, they may break before they look bad. Before making a long
offshore passage, I inspected my rigging carefully. Everything looked
fine. At the end of the passage I found a broken strand of 1x19 wire at
a swage fitting. Admittedly stainless steel wire is horribly expensive
(3/8" 1x19 is in the vicinity of $2 per foot), but I'd replace it all if
I could afford it.
|
979.6 | how would you determine size required? | LEODLN::BAHLIN | | Tue Sep 20 1988 14:23 | 16 |
| re: .5 hmmmmmmm.......
Good questions. This boat is not in my hands yet so I can't easily
verify the wire type. I'm going from memory on 2 test sails (nice
owner). I'm pretty sure that it is 7x19 though. Given your
information on strength of 1x19 5/16" I am tempted to ask another
question. Why would the boat be rigged with wire meant more for
flexible applications? Could it simply be that somebody got a deal
on this stuff or are there more subtle advantages?
The larger question is.... what would be a good way to determine
an appropriate size based on rig data? What if this boat is needlessly
over rigged for offshore work and its offshore days are over?
|
979.7 | a possible explanation | MSCSSE::BERENS | Alan Berens | Tue Sep 20 1988 15:07 | 17 |
| Well, since I don't how the boat is actually rigged ...... The
stays/shrouds on many older wooden boats are attacted to the mast by
splicing an eye in the stay/shroud around the mast. A block of wood or
groove in the mast keeps the spliced eye from sliding down the mast
under load. I don't recall the rules for minimum bend radius for the
various kinds of wire. For 1/4" 1x19 wire the minimum radius is on the
order of 3" (implying a minimum mast diameter of 6"). The minimum radius
is much less for 7x19 wire. If the boat is rigged as above, this is
probably why 7x19 wire was used.
The approximate rule I've heard is that the breaking strength of the
fore and back stays and upper shrouds should be at least equal to the
displacement of the boat (eg, a breaking strength of 12000 pounds for a
12000 pound displacement). This may assume a modern, high aspect ratio
rig, and perhaps less strength is needed for a low aspect ratio. There
are several books available that discuss this or call a spar maker.
|
979.8 | I see the light | UNIVSE::BAHLIN | | Tue Sep 20 1988 16:31 | 12 |
| I never thought of the radius as a driver for the wire type but
it makes more sense than anything else. The upper part of the stay
is attached as you described (with a big loose splice in a groove)
with lots of radius. The lower part however is around a galvanized
thimble which (big guess now) is no more than 2 inches I.D.
The thimble could explain the need for 7x19 instead of 1xXX. Maybe
the previous rigger traded off swaging costs against cable costs
to arrive at the current configuration. I think a letter to the
builder might reveal the original specs and is probably well worth
the postage.
|
979.9 | another case of 7x19 used | CDR::SPENCER | John Spencer | Wed Sep 21 1988 11:00 | 11 |
| FWIW, PUFFIN had 7x19 shrouds, spliced in big loops that were placed over
the masthead and held from slipping by a pair of little (4" x 1/2") bronze
dogs through-bolted on each side of the mast near the peak.
Being a gaff ketch, she was definitely "traditional tech", and quite
surely overrigged, since she theoretically could fly full sail without any
shrouds in winds up to 20kts or more -- thanks to a mainmast 10" dia at
the partners. Wire size just never seemed an issue. ;-).
J.
|
979.10 | | GONAVY::GINGER | | Thu Sep 22 1988 09:35 | 12 |
| All of the old boats Ive been around used 7x wire, not the 1x for
hte reason of splicing- I dont think you can splice 1x19 wire.
Id have a talk with an outfit called "The Rigging Gang" They usually
advertise in WoodenBoat. The owner came to our TSCA meeting last
year and gave a GREAT talk on tradditional rigging. I believe he
really knows his stuff, and more importantly, knows how to get the
material thats so hard to come by these days. Although I had always
assumed from their ads they only did the massive rigging jobs, Like
Pride of Baltimore of Spirt of Mass, they do small jobs for private
owners.
|
979.11 | | GONAVY::GINGER | | Thu Sep 22 1988 09:45 | 20 |
| This may be more legend that true, but an oldtimer once told me
a story to favor spliced wire over swaged or other end fittings.
On large (read HUGE) cranes, the main stays to the boom are a pair
of wires up the back called 'hog rods' Because cranes use various
combinations of boom length, the hog rods need to be made in sections
and joined, so a typical crane has up to a dozen or more joints
in the hog rods. The wire can be 2-3 inch stuff, so splicing them
is not cheap. When the swaged fittings first started to be available
Manitowc tried them. A big demo was set up for some important people.
One of the joints failed and the whole boom collapsed in a heap.
Many years later Manitowc still used spliced joints on all hog rods.
The real advantage of spliced joints is lack of surprises- you can
quite simply inspect the splice and be reasonably confident of its
condition. Looking at other fittings you cant really tell much about
its strength, except for very obvious things like broken strands
or major corrosion. Without X-ray or Magna flux or other testing
procedure how do you know there isnt some internal problem?
|