Oh knowledgable ones: I just realized that my spreaders are off balance. One is maybe 3 inches too high and the other 3 inches low on the diamond wires. I think they were making a sound when gybing last weekend- everytime we changed tacks you heard a loud pang. I didn't really notice until today. The mast is still up and I am going to be taking it down to take the boat home, but I was wondering if anyone had any experience with this and have any suggestions on how to fix it. Could it be as easy as making sure the attachment to the mast isn't horrendously bent, straighten them, then use seizing wire to make them stay put again. Any suggestions?
I just had a spreader break on my N6.0na, and that caused the mast to break. The front adjuster screw sheared right at the Y. The only cause I can think of is metal fatigue when I had the spreaders go up/or down and had to slightly close the Y with pliers. I think this caused metal fatigue. I would recommend that if in doubt, get a new spreader kit and then tie the spreaders tight to the diamond wires with several short stainless wires.. Dave
I just had a spreader break on my N6.0na, and that caused the mast to break. The front adjuster screw sheared right at the Y. The only cause I can think of is metal fatigue when I had the spreaders go up/or down and had to slightly close the Y with pliers. I think this caused metal fatigue. I would recommend that if in doubt, get a new spreader kit and then tie the spreaders tight to the diamond wires with several short stainless wires..
Dave,
For a short period, there was a problem with the 6.0 spreaders where the threads of the adjustable part were threaded too closely to the slot milled out for the attachment to the mast. It took too much meat away resulting in occasional failure. I'm not sure if there was any factory warrantee on that or not (probably not).
PTP,
The Nacra spreaders have a good deal of play up and down - we could move the Nacra 20 spreaders up and down 3 to 4" as measured at the tip with no diamond wire tension. This is not a problem as long as you keep them perpendicular to the mast when tightening the diamonds. You should always have at least 300 to 400 lbs of tension on the diamond wires which should easily keep the spreaders in place...chances are that your diamond wires are too loose. A little retaining wire won't hurt either.
Jake, Thanks, you said what I wanted to hear. I will see how things look when I get the mast down. What is the best way to check/measure the tension on the diamond wires?
BTW... I just ordered the Vertglas kit and will back you up if all goes well
We had the same problem last year with one of the spreader working its way down a little, not as much as yours. Certainly check your spreader screws, we replaced our because of the threads. There was a notice from the factory to replace the spreader screws, but it was some time ago. We replaced the screws and made sure to tie them tightly in place with some thin stainless wire as I recall. Jake mentioned 300 – 400 lbs. In talking with Rick Bliss, he directed me to the NENSA website that has a tuning guide. From this guide we set the mast up according to the big crew setting since we average between 380 and 400 lbs. From memory, so check the tuning guide, with the mast on supports we set the spreader rake to 1.75” and then tighten the outer diamond wires to 500lbs, resulting in 1.5” of pre-bend. There is a note that also says never let the pre-bend be less than 1.25”.
Your post signature says …6.0Ex. Does that mean you have the actual, much talked about and feared “Express”? The first race we did with our 6.0NA with Smyth square-top main and big jib, we were hammered with the Express rating even thought we didn’t carry a spin. Since then we have over come the “Express” fear by comparing the square-top main to the standard class sail. It was noted that the square-top sail was not bigger, but that the sail area was allocated differently. We did not that the jib was about 6% bigger than the standard NA jib. Do you have any other pictures to share? Rick Bliss is a very valuable resource for the 6.0.
Yep, I have an "express" (as far as was told to me when I bought the boat and everything else I know about it). It has a monstrousity of a jib that does backwind the main pretty quickly if you aren't paying attention. I have been told that the downwind performance of the express is almost second to none (except spin boats of course). HOWEVER, I have yet to experience it and am workign on practicing downwind runs better. I know that my total weight is an issue (not me, I am 160, crew is 230) for downwind but it seems like there is something else we are missing. I am somewhat new to catamaran racing so I am figuring things out as I go along. I sort of like tinkering with the boat but am afraid of breaking stuff as I tinker with and/or fix it. I did check out the NENSA site and it does seem to be helpful. I will let you know how it turns out. BTW- the problem with the threads on the spreaders- what model years had that problem? Mine is a 1990.
REPLACE THE SPREADER ENDS! REPEAT! REPLACE THE SPREADER ENDS!
Two things: the threads on the lower one in this picture are too close to the milled grove resulting in weakening the material badly there. Secondly, the 'ear' is bent on it which will quickly lead to a fatigue failure. Seriously, replace those adjustable ends before sailing again and make sure you are running adequate diamond wire tension. The parts and tools are a lot cheaper than a new mast.
New Eng Cat referenced Murray's site so I just ordered them from Murrays- I called Rick but they are closed until monday. Should have waited, given that they are on back-order at Murray's. oh well... MO MONEY MO MONEY... ordered a loos meter as well... and awaiting my new mainsail. Gotta start working more (gotta work hard to play hard) thanks for your help.
Dang, you are going to be stylin' soon! (sorry - just watched "Joe Dirt"). I'm glad you got everything in the works! You'll have to take me for a ride if I make it down that way.
Jake Kohl
Re: Spreaders bent?
[Re: Jake]
#57843 09/24/0508:31 AM09/24/0508:31 AM
Jake, I figure I owe you more than a few beers by now so if you make it down here I would be happy to (you probably could teach me a lot too.. which would lead to more beers, I think you'd be set) pp