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Hi all,

I am about to commit to a Dynex Dux rig for my Tiki 38 but I want to be sure about sizing.

Can anyone tell me the design loads for the standard Wharram rig for this boat (that is crab claw soft wing schooner)???

Thanks

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Jamie,

If you are going to use stainless for the forestay, suggest you follow Ann and Neville's advice on rigging the forestay. Ann can break in and tell their story, but basically, after it broke underway, they replaced it with a straight forestay with loops for a shackle on both ends, doing away with the eyesplice at the top. The forestay is then shackled to a padded steel line with a loop at both ends that goes completely around the mast. The shackle connects the two ends of the mast line with the forestay. Experience from several boats indicates that there is enough jerking around side to side that the forestay eyesplice can fatigue at the splice and break, leaving the mast unsupported in the front.

When we have the forestay loose, I take the forward halyards down to the ends of the one beam and tension them temporarily using a truckers hitch to hold them in place and move the masthead foreward while we tighten up the forestay. You could leave them in place if you wanted; I certainly think they are capable of holding the masthead temporarily if the forestay should break. On Mouzzer these halyards are normally led to the ends of the two beam (per plans) and go through a rope clutch on their way to the big winch. One is normally up (either for the jib or the chute) all of the time, so they're not available to protect the mast.

I would also suggest the builders make the jib halyard internal, rather than using an external forward halyard for the jib. I am sorry we did not do that. Because the external halyard is led to the starboard end of the two beam, tightening it pulls the masthead to that side. Consequently, when we are on port tack and the wind comes up and we tighten the halyard, then tack, the jib is again loose (because the wind has pushed the masthead to starboard, and tightening the halyard again then puts a frightening amount of force on the mast (at least it seems so) on starboard tack, which is made worse when we tack back on to port and the masthead again shifts to leeward. The remedy is to lead the jib halyard down the mast and then aft to the winch, but this interferes with the leading edge of the foresail and requires extra fittings at the base of the mast. Making the halyard internal is the right choice.

Also would take Ann and Neville's advice about the bungee chord on the two aft shrouds, and getting the shrouds as tight as you can. Very disconcerting to see the shrouds flapping in the breeze.

Ron
The reason Peace had trouble with her forestay was that we hired a rigger to assist us in order to save time. He fashioned a loop to go around the foremast at the top but he used galvinated wire and a choke and that is clearly improper. As I say, we were in a rush to get out of British waters while the insurance was available to do so (ie before autumn gales began). The rigger's loop broke when we were doing 9 knots to windward all up in strong wind off Cape Charles and it broke with a loud BANG and left the mast held up by only the halyard and the shrouds which gave side support only. The mast was held by the mast case while Nev lowered the fore sail and I rolled up the jib and we were grateful both sails came down so easy. We turned back to Norfolk and Nev made a temporary fix until we could remove the mast, make up a new stainless steel loop, repair both mast and mast case, and have everything strong and proper. I think there is no fault now. We have roller furling and the furling equipment came with that forestay.
Our halyards go along the aft side of the masts to clutches located there. We have rope lacings on our sails and like them very much for their easy up and easy down action. I do think the wrap around sails give a lovely shape, but easy is more important to us than speed at our age. But saying that, we did 15.5 knots sustained with only the main and fore sails up recently with a quartering 25 knot wind, and that is fast enough for the likes of us.
Safety is important to us, and so is easy, and speed comes after that.
Ann and Nev
HI, On Peace we have the little wooden cleats (hooks) at the tops of the masts extra fastened with small threaded rod thru fastened to the opposite cleat and glued with epoxy and also recently filleted by me for extra security because it comforts me in stormy weather. If you have anything running through the inside of the mast, you must provide chafe gear against damage from the threaded rod such as a plastic water pipe pipe for wires etc. Ann and Nev

Jamie Rohan said:
Oh and another question for those patient souls that have built their T38's, or have access to plans!. Can someone describe for me how the mast shroud "cleats" are constructed. These little bitty hooks at the top of the mast which the shrouds loops hook around. Do they have a thru bolt or something other than epoxy holding them on?
Hi Ann and Nev.
Would you have a photo of the SS mast band that your f'stay attaches to? This sounds like a great idea.

Thanks all, for ur info
The standard rig for the Tiki 38 is a schooner with gaff luff pocket wing sails. The crab claw is an entirely different rig. You can use 6mm Dynex Dux as far as working load goes. I prefer to go with a larger diameter. This allows for creep to be less of an issue and also provides more reserve strength and is easier on the hands. We have been very happy with the Dynex on our Tiki 30. I also like to use the spectra line for the deadeye lanyards and the beam lashing frappings as it is very slippery and enables much tighter lashings. David
Hey David, which deadeye fittings did you go with? I've been looking at the Colligo and Precourt options. I like the precourt SS chainplate fitting. I was a little concerned about electrolytic deterioration with the alloy fittings on my SS chainplate. They are too expensive not to be concerned about longevity!

So you found that spectra was "slipperier" than the dux? Any concerns about load ratings with spectra?

Jamie
Jamie,
I went with Coliggo. I found them to be much more responsive than Precourt. John Franta at Coliggo has been very helpful.
Dynex Dux is spectra that has been prestreched according to my understanding. David
Hi Jamie,

Nice pictures, I spotted some good mods on the rigging indicating that you know a bit about boats. How is the main sail traveller working out. After seeing it I am wondering why I had not the idea myself:-)

If you are interested I have digitised all relevant construction details.

Regards Björn
Hi Bjorn, thanks, yes the traveller works well. Certainly adequate to get a nice shape on the sail, and get all those telltails streaming. The "traveller rope" (track) is anchored around the beam ends with 1" tubular webbing. I also use 1" web for my headsal blocks. So far the only rot i've had in the boat is where the headsal tracks where mounted on the beam, so I got rid of them and their nasty little screw holes, and just use webbing around the beam.
I've added a couple more pics which show better the traveller arrangement.
And also sent you message regarding your offer!


Björn said:
Hi Jamie,

Nice pictures, I spotted some good mods on the rigging indicating that you know a bit about boats. How is the main sail traveller working out. After seeing it I am wondering why I had not the idea myself:-)

If you are interested I have digitised all relevant construction details.

Regards Björn
It is not a stainless steel mast band. The wooden cleats are through fastened through the wooden mast so the port side cleat and starboard side cleat are thru fastened to each other. Ann and Nev

Jamie Rohan said:
Hi Ann and Nev.
Would you have a photo of the SS mast band that your f'stay attaches to? This sounds like a great idea.

Thanks all, for ur info
Hi All,

Just thought I'd make an update my rigging on my T38.
Since my last post I have replaced all my shrouds with 7mm Dynex Dux. I purchased the Dux from Hampidjan in New Zealand, whom offered the best price (considering exchange rates), and the fittings came from Colligo. I found the brummel splicing a breeze with the help of the video tutorials on the Colligo website.
My wife and I have only had a two day sail in about 15kts so far, but i am very pleased with the rigs. I've been able to get some solid tension by using a halyard down to the tail of the lashings.
We live in Brunei, SE Asia, where there are "NO" supplies for yachties, and trying to get 1x19SS flown in, and then find someone to hydraulically swage seemed impossible. Hence one of the many reasons we went with DUX. It was completely DIY!
I will be replacing the forestay with SS when I get a chance, since i've got the roller furler. However, I will be modifying it so that has a thimble at the top, which will shackle to a DUX loop that goes around the mast. This should remove the risk of the SS loop fatiguing. There's a pic of my new shrouds on the website.
Thanks to all those that offered advice about this type of rigging.
why don´t you use Norseman or Stalock terminals? They are expensive but you can do them yourself and the can be reused.

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