For those of you who use these - any caveats to their use on a beach cat? Assuming new shrouds terminating with a fork instead of a thimble - how did you measure the length of the new shroud needed and who made 'em for you?
Personally I’m not a fan. I lost a rig one day as the leeward sta-master unwound while going upwind…tacked over, boom, no shroud. So you need to tape the clip in place anytime you make an adjustment.
I use these instead: https://www.ronstan.com/us/turnbuckle-body-calibrated-lock-nut-1-4.html
with this fitting on the end of the shrouds/forestay: https://www.ronstan.com/us/t10-swg-terminal5-32-wire-1-4-thread.html
Murrays can make the correct shrouds. For length, you’ll want to take your existing set, measure eye to termination eye (including the existing shroud adjuster) then take the turnbuckle + threaded shroud fitting set about halfway down the turnbuckle and do the math on wire length.
Good info - thank you. Can you adjust them while the shroud and its terminal is threaded into the turnbuckle?
Personally I’m not a fan. I lost a rig one day as the leeward sta-master unwound while going upwind…tacked over, boom, no shroud. So you need to tape the clip in place anytime you make an adjustment.
Well, just like with everything else on any sailboat, small or big, fasteners need to be backed-up with safety-wire, tape, or whipping, etc. Sta-Masters are likely the most implemented, easily-adjusted and secured turnbuckles on shrouds on smallish boats.
Any form of turnbuckle needs to be doubly secured. Even the Ronstans should be doubly secured in some method (taped). If the lee shrouds are loose enough to whip around, the lock nut can loosen. Then you'd have the same problems.In fact, there's no provision to safety-wire those Ronstans unless you drill a safety-wire hole through the edge of the lock-nut. Even then, there is not much else to secure the safety-wire to, to prevent the lock nut from loosening.
I could believe that even if the Ronstans are taped, the lock-nut could possibly loosen if not checked before every outing or on a long-distance sail, and the loose shroud could theoretically make the adjustment nut unwind about the threaded swage terminal.
I've had all manner of fasteners loosening due to vibrations and whipping. I will never trust simply tightening a shackle screw or lock nut... these must always be doubly secured and 'pre-flighted' before every day-sail. On my bigger boat (33 ft, 7-ton sloop) I climb the mast a few times a season to check all the rigging connections and blocks. Everything is safety-wired AND taped.
I was on a 150 mile -long distance race on a friend's 32 ft racer/cruiser, and around 0130 hrs (very-early morning) in heavy-ish seas (20-25 knots wind), under a single-reefed main and 90% blade jib with five big guys on the rail, the mast collapsed and went over the side due to a shroud fastener failure at the masthead. The incident could have killed one of our crew who was on the windward rail at the time, sitting right at the main-shroud/intermediates chainplates. The intermediates tore into his shoulder and pined him against the coach-roof. We were 35 miles offshore on a hard beat on the return leg. The crew, in their shocked state, were thinking about trying to retrieve the sails(!) and the deck-stepped 40' mast(!!!) and boom in rough seas, all of which were threatening to punch holes in the hull with every heave, roll, and yaw in the waves. I knew this was completely impossible, so I started disconnecting all the shroud and stay base connections. We took our GPS position a couple times and let the rig descend into the depths and ensured that we secured or cut all lines that could entangle the prop. Good thing the engine worked well.
That friend was more of a portly type who never climbed his mast rig to verify all the rigging connections.
Yeah, I like the Sta-Masters. I've never had any problems with these on my smaller boats. I especially like these because you don't absolutely require a wrench to adjust and secure (lock) them. Add your crew's weight to the trapeze and the adjustment nut is easily finger-manipulated, then the nut-clip is easily clipped into place and then taped or tied (waxed whipping twine) and taped.
For those of you who use these - any caveats to their use on a beach cat? Assuming new shrouds terminating with a fork instead of a thimble - how did you measure the length of the new shroud needed and who made 'em for you?
I recently ordered a whole rigging set for my C2 F18 from Goodall Design (through Jill Nickerson). Like some of my past cats, it has the Sta-Master shroud adjusters. They needed my HIN (hull identification number) as well as another hull measurement since there have been some rigging revisions throughout the C2's production.
Anyway, Murray's and other riggers likely have good rigging measurements to go by given that you have a well-known production cat, but also be aware that rigs could have been modified throughout the cat's production years.
To ensure that you get exactly what you need in lengths, you could tension an existing shroud, the forestay, and a bridle between two trees or other hard-points (two vehicles, tractors, etc) and take accurate measurements. The forestay usually has a pigtail with a block for the jib halyard, so you need to get accurate measurements of that pigtail and it's position on the stay as well.
Obviously, note the type of swages that terminate the rigging ends.
Last year I made and replaced the rigging of one of my hang gliders. Both ends of each of the wires were merely thimble termination with two nico's per thimble. Since each original rigging piece was less than 10' long, I simply set up a 10' 2x4 with nails on each end, spaced longer than the longest piece of original rigging, put one thimble-end of the existing wire on one nail, then tensioned the wire with a 1:4 purchase of twine through the other thimble and nail. Tensioned the wire just enough so that it lay perfectly straight and flat on the 2x4, then added another nail to that second thimble into the 2x4 for the purpose of making the correct overall length of the new piece of rigging. Fabricated the new wire and thimble-end, put the thimble-end over one of the nails, then added two nico's and a thimble over the other nail with plenty of wire-tail so that I could add a length of twine with a trucker's hitch to that tail, and with that tensioning the whole wire. Cinched-up the two nico's to the thimble and compressed those nico's. After nico-pressing, I cut off the remaining tail with a cut-off grinder wheel, then slipped and shrunk the heat-shrink tubing over the cut end and nico's that I had previously slipped on the wire before the nico's were added.
I tested each wire with 300 lbs tension and re-measured before installing on the glider. Flying at 7000' + above ground (and especially only 100' agl) entices one to ensure as perfect as possible mechanical connections.
Obviously, most sailboat rigging have bottom swages instead of thimbles, requiring hydraulic and drawn swaging machines.
Personally I’m not a fan. I lost a rig one day as the leeward sta-master unwound while going upwind…tacked over, boom, no shroud. So you need to tape the clip in place anytime you make an adjustment.
Well, just like with everything else on any sailboat, small or big, fasteners need to be backed-up with safety-wire, tape, or whipping, etc. Sta-Masters are likely the most implemented, easily-adjusted and secured turnbuckles on shrouds on smallish boats.
Any form of turnbuckle needs to be doubly secured. Even the Ronstans should be doubly secured in some method (taped). If the lee shrouds are loose enough to whip around, the lock nut can loosen. Then you'd have the same problems.In fact, there's no provision to safety-wire those Ronstans unless you drill a safety-wire hole through the edge of the lock-nut. Even then, there is not much else to secure the safety-wire to, to prevent the lock nut from loosening.
I could believe that even if the Ronstans are taped, the lock-nut could possibly loosen if not checked before every outing or on a long-distance sail, and the loose shroud could theoretically make the adjustment nut unwind about the threaded swage terminal.
I've had all manner of fasteners loosening due to vibrations and whipping. I will never trust simply tightening a shackle screw or lock nut... these must always be doubly secured and 'pre-flighted' before every day-sail. On my bigger boat (33 ft, 7-ton sloop) I climb the mast a few times a season to check all the rigging connections and blocks. Everything is safety-wired AND taped.
I was on a 150 mile -long distance race on a friend's 32 ft racer/cruiser, and around 0130 hrs (very-early morning) in heavy-ish seas (20-25 knots wind), under a single-reefed main and 90% blade jib with five big guys on the rail, the mast collapsed and went over the side due to a shroud fastener failure at the masthead. The incident could have killed one of our crew who was on the windward rail at the time, sitting right at the main-shroud/intermediates chainplates. The intermediates tore into his shoulder and pined him against the coach-roof. We were 35 miles offshore on a hard beat on the return leg. The crew, in their shocked state, were thinking about trying to retrieve the sails(!) and the deck-stepped 40' mast(!!!) and boom in rough seas, all of which were threatening to punch holes in the hull with every heave, roll, and yaw in the waves. I knew this was completely impossible, so I started disconnecting all the shroud and stay base connections. We took our GPS position a couple times and let the rig descend into the depths and ensured that we secured or cut all lines that could entangle the prop. Good thing the engine worked well.
That friend was more of a portly type who never climbed his mast rig to verify all the rigging connections.
Yeah, I like the Sta-Masters. I've never had any problems with these on my smaller boats. I especially like these because you don't absolutely require a wrench to adjust and secure (lock) them. Add your crew's weight to the trapeze and the adjustment nut is easily finger-manipulated, then the nut-clip is easily clipped into place and then taped or tied (waxed whipping twine) and taped.
Glad you guys got out of the mast lost situation OK, and hope the pinned crew recovered fully!
On the whole I concur with a secondary retention feature on fasteners/shackles etc, however when it comes to the Ronstan-type turnbuckles (Blue Wave also make a similar set) I have found the locking nut that rides on the threaded turnbuckle doesn't come loose, once secured with a wrench. If it did come loose, it would be >56 turns to end up disconnecting. The other advantage are these are much easier to adjust at the high tension levels (30-34 on the loos gauge, 335-460 lbs) we are using on the epoxy F18's to reduce headstay sag. It would be a struggle with the Sta-Masters to get this tension level.
The latest bluewave turnbuckles Nacra are shipping can be adjusted without a wrench set as they have large plastic knobs on the turning nut and a nut that can be locked down by hand.
The clip on the Sta-Masters is almost non-existent compared with a proper nut; it only holds up for a few uses.
I was thinking something like this might make my life easier, but on reflection and with the aid of all your help, I think I'm just gonna stick with the tried and true 10 hole stay adjusters. Thanks for sharing your knowledge.
-Matt
On the whole I concur with a secondary retention feature on fasteners/shackles etc, however when it comes to the Ronstan-type turnbuckles (Blue Wave also make a similar set) I have found the locking nut that rides on the threaded turnbuckle doesn't come loose, once secured with a wrench. If it did come loose, it would be >56 turns to end up disconnecting. The other advantage are these are much easier to adjust at the high tension levels (30-34 on the loos gauge, 335-460 lbs) we are using on the epoxy F18's to reduce headstay sag. It would be a struggle with the Sta-Masters to get this tension level.
The latest bluewave turnbuckles Nacra are shipping can be adjusted without a wrench set as they have large plastic knobs on the turning nut and a nut that can be locked down by hand.
The clip on the Sta-Masters is almost non-existent compared with a proper nut; it only holds up for a few uses.
Yeah Sam, those Blue Wave turnbuckles are nice looking.
Just looking at the Nacra Evo F18 Tuning sheet, Rig tensions look pretty high (180 - 220 kgf [396-485 lbf]). Much higher than what Goodall recommends for their f18 boats (50 - 100 kgf [110-220 lbf]) Those Evo hulls must be quite stiff if they're not deflecting at all at the bows.
The clips on the Sta-Masters on my C2 are 16 yrs old now and still functioning. Of course, I recently purchased the boat, so ..... But on previous boats, I just applied a small smear of lanolin to the threads and the nut turns easily with load, slide the clip up and tape or tie it down.
https://bluewave.dk/products/quick-race-tuning-qrt-toggle-terminal-2/
https://bluewave.dk/products/quick-race-tuning-qrt-hand-operated-turnbuckle/
I have used, and still have Sta Masters on my Tornado. Used to own a rigging company so familiar with turnbuckles.. The Ronstan adjusters are very nice but pricey and heavy. They do have an adjustment lever for easy adjustment. On my Prindle 19, I did a lot of singlehanded sailing so I installed a standard open body turnbuckle with locking nuts... I will say, one time we didn't tension the nuts enough and the leeward shroud came loose... nothing like being 2 on the wire and you hear a pinging/banging noise... my crew then asked if "that" should be attached... he jumped down and luckily the barrel stayed on the bottom toggle (always wind the bottom about 2 more threads than the top) and he was able to reattach the shroud before we had to tack because of land approaching. On my modified 18-2, I use lashed Dyneema as adjustment.