More about Dyform & Dux rigging options...

[Mark Johnson]

Followthrough about Dyform wire & Dux rigging

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Thanks Allene for the "new thread" tip... My being amoung the computer challenged! Now I'll try to post this in the correct place:

Thanks for the response Brion, I appreciate your help.
My appologies for computer ignorance. I still don't get how to start a new thread, or if there is a correct one that my questions should've been in, Most of the last two decades I have been absorbed in a boat project or "out there cruising", and with no computer connection...

My Sta Locs & proper installation...
I have taken them apart after over 10 years and the inside was pristine. No I didn't follow the instructions "exactly". I use 5200 and fill them about 60% full. First I form the wires, then open back up & make sure that no wires got in the slot.. Then I wrap a piece of tape 1/8" up the wire from where it exits the Sta Loc, and put in the dolop of 5200, and screw them together with blue loctite on the threads. A really good ooze of caulk comes out the top of the Sta Loc, but is stopped at the tape, which I then remove, and wipe up the excess, being carefull not to create a concace at the wire's exit point. This has worked well for me. One thing that I learned the hard way, is that if I put in too little caulk the first time around, and open it back up to put in more caulk, the threads that now have 5200 on them, MUST be completely cleaned before the second attempt. The combination of 5200 and blue LocTite on the threads, will never set up, and just keeps the threads lubricated! I unscrewed one once to shorten a wire, (very early on) with almost "finger pressure", from having made this mistake... Now I just make sure that I have enough caulk in there the first time around!

I was told by Sta Loc that in using Sta Locs over again, the fact that after I clean up the inside of the barrell & threads well, my "formers" are essentually still glued in there, is not really a problem. They claim that after putting on my NEW wedges it simply makes "forming" the new wire a bit fore dificult, but there is no need to remove the old "formers".
Do you agree with them about this?

Re-tune, Creep / stretch, & age...
It sounds like my rig, @ 14 years old, is in fact long over due. The fact (and my excuse) that everyone over taxes the wires lifespan, is no consolation. Good that I'm getting on it now! Perhaps I haven't explained well... I have only put one extra turn on the turnbuckles in over 20,000 mostly tropical sea miles, and 14 years. (2/3rd Fl or Caribbean, & 1/3rd NC or SC) The sagging off of the mast's top 1/3rd from streatch, has always been there from sail #1. The main chainplates on our Searunner are massave. They are exterrior mounted on a double thick area of the cabin side, (which passes through the deck & becomes the hull), and are located about 4' or 5' from the cabin side port. Over the last 40 years, I have built all 3 of my cruising boats to a standard so high that it has caught me a lot of good natured grief from other boat builders. This one took my wife & I over 10 years, 7 of them @ 100 hrs / week between us! So it is not the chainplate's holes, which got perhaps 20 coats of epoxy in each of 8 holes, or the structure. Also, since both the intermediate shrouds, and cap shrouds, come down and attach to the same 4" wide X about 2' long chainplate, yet only the cap shroud stretches noticably, I assume it is the fact that that wire has twice the load and 35 or 40% more length, causing it to streatch, and the top of the mast to fall off... Bear in mind that I'm talking about a loaded old cruising boat, going almost 9 knots to windward, in winds gusting to 30! When out "cruising" VS "day sailing", I never do this... I reef the main, strike the roller furling lapper completely, and raise the staysail. This levels out the boat, the mast is straight, and I have to live with 8 knots of boat speed. If it wern't for the fact that changing the wires is long over due, I'd solve the problem by sailing like a sane person. Since I have to re-rig anyway, I'd like to solve the problem at the same time. This way, In our local protected waters, I'd have the option of sailing like a wild man!

Other considerations... I have no doubt that things have changed on our boat a bit over the years, which would account for a slightly overall slacker rig.. The hull may have given a bit, bottom of the mast corroded a bit, mast tangs & chainplate holes elongated a bit, etc. However, since this "streatch on the uppers" problem was there from the get go, It's the one that I want to get right this time.

Dyform / Compact Strand Wire...
I only have a turnbuckle on my back stay, not hydraulics. The previous information I posted by Navtec said that the direction of Dyform's attempted un-lay, would try to "tighten" StaLocs. (Do you agree) The sugestion that I made of "put a half turn of pre spin on the Dyform wire", as I cotter the adjusted turnbuckle, was meant to be in the direction that would be slightly tightening the lay of the wire AND the StaLocs. This way the twisting tension may vary a bit in the gust, but the spin in the lulls would never go past its static position and try to un-screw the StaLoc. (there would always be a slight at rest, to more pronounced in the gust, tightning force on the StaLocs. Does this make sense? Can the twisting force be so pronounced that it might not be held at bay by the turnbuckle's cotter pins? I really like StaLocs, but don't want to risk this wire trying to un-screw them. Should I avoid this product for these reasons? Otherwise I'd just make the change up to 9/32" 1X19.

Dux issues...
It is good to hear that you feel that the safe lifespan of Dux is comperable to SS. I like the concept. I have already ordered it for my runners. Unfortunately the sleeves have to be removed for my 1/2" pins to fit the 7MM terminator's hole, but I'll Tefgel the pins & holes, and keep an eye on them...

In the case of my upper shrouds, I have been seeing the top of the mast move from mostly straight to bending off perhaps 5" in the gust, and spring right back. (in the above sailing conditions) In some web article you said that after a gust, the "under reasonable load stretch recovery" of SS was "quicker" than with Dux. This seems like a problem if I was to use it on my uppers. However IF I am using 9MM Dux, would this huge oversize in strength make this stretch recovery issue go away, and minimize the creep issue.
Should I consider this rather than wire on my uppers, as well as the rest of the rig?

They mention on a 50' shroud a .5" of creep / year @ my perhaps 1,600# static load. Since this would be incrimental, rather than all at once, I would think that I'd have to take up 1/8" every 3 months... Is this correct? Corrected question... After reading your post that with properly sized Spectra, a milder static load than wire will suffice... Perhaps I could have half of my old static load on the uppers, (like 800#s)? On 9MM Dux would this then bring the creep down to almost "0"?

Covers for Dux...
Is it worth the expense, extra weight, & windage?
It is encouraging to learn that the 5 year lifespan estimate on Dux is conservative, & rated "in the tropics". With our home base now being NC, I doubt that we will spend more than 3 out of the next 10 years cruising the tropics. This, and if we were to use much stronger 9MM Dux to replace 1/4", 316 SS, might make 10 years a safe lifespan for us. Do you agree?

Don't use a snapshackle on my runners...
My snapshackle is rated at a 3,525 lb WL. It is attached to the end of my running back stay by a clevis pin through the snapshackle's forks, going through the stay's StaLoc or Dux "terminator's" eye. Being a permanent part of the wire, not the turnbuckle, this is snap shackled to the large "regular shackle" at the top of it's "T handle" quick adjust turnbuckle, which is permanently bottom pined to a chainplate on the hull. I snap it on & put on 5 turns with the handles, and it takes like 30 seconds! When not in use, I use a bunji to the lifeline wire to store the "now loose" top end of the turnbuckle Why not use it for this? Speed of removal & replacement is a safety issue too. Especially under the conditions where I'd be rigging it up! (>30 knots)

Thanks again Brion,
Mark Johnson


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