So.. went over a rock.. Hit the rudder... Not too Fast.. Pivmatic did not release. Tested it when installed and thought it was too firm. Had to YANK ! HARD on the strap to get it to release after instalation.. Now I have a rudder that has the line that pulls it down into position.. that has split the shells of the rudder at the top hole and the rudder is too fat for the casting.. Two issues.. 1.. Do I need or want to remove some material from the 3/4 tube on the pivmatic to ease the tention required to have it release. 2 How to fix the rudder. Your advise on question one please. My thoughts on #2. Take a hacksaw and cut a bit of foam from the seam between the halves of the rudder blade.. Epoxy and clamp to rejoin to the proper thickness of the blade (It began to rub on the casting after that happened and would not fully seat}..
Having a great time with her.. Learning a lot about getting her to tack and about her balance. Thanks to all !! Still can not fathom how moving 1 to 2 feet forward from the back X Member makes that much difference in speed.. She loves to keep her nose under water.. Trying some mast rake trials as well as main downhaul changes and rotation adjustments..
Update report.. None done cept new lines. Will do Jib blocks under the tramp over winter Thank God.. Lost a pint or two of blood.. .. New Trap line strung with a small bungie on the front X Member on the front outside of the tube with the straps that used to be inside for the righting line inside.. Righting line folded under the center post behind the mast... May keep the center pole.. I Can sail ANY DAY in SF Bay areatill Sept 1 . IM for a time !! 1 boat is nice.. 2 is a race.. (Yes I will get a new pic of her soon !! She is shy) Thx Hal
Answer #1: don't change the pivmatics. They work flawlessly when you have the whole system tuned properly (i.e. quality proper size line and alum clamcleat, etc.)
Philip
The pivmatics are extremely tight until they've popped a couple times, then they work just fine. Don't change them.
Also, make sure you're using a 1/4" clevis pin and not a bolt/locknut to hold the piv's on.
Rob
Nacra 5.2
OKC, OK
Remember if you add any purchase to lower the rudders, even 2 to 1, it will take half the effort to lower the rudders, but it will now take twice as much to kick up the rudder pivomatic and if you have a 3 to 1 it will almost never kick up properly
I've neer had a problem with the 2:1 but my pivmatics are pretty loose. If you had 2:1 installed then that would be your first change. Otherwise take a look at the installation, I've seen some crazy things - bolts instead of clevis pins, pivmatics installed backwards, etc.
We need to get a picture to take a look at it to tell you how to fix it. Likely not a terribly difficult repair. Probably just dry it out, inject some thickened epoxy into the cracks and some wood cauls and clamps to glue it back together. Then some fairing with thickened epoxy after. Upload some pics and we can help you out. I'm researching how to make new rudders right now since the costs have gone throught the roof. Haven't found a good source of foam blanks as of yet though.
D.
Dave Bonin
1981 Nacra 5.2
D.
I think I have a pair of extra rudders.
Philip
I recently upgraded my worn out plastic cleats with new aluminum clamcleats from Murrays and the Pivmatics are now holding the rudders down much better. So far I've only hit one rock (slowly) and the pivmatic popped right up.
Eric
Nacra 5.0
Trac 16
I use an eyestrap (R2828) aft of the pivmatic, w/ an open aluminum clamcleat on the piv. It was born of necessity, but I've changed all of mine over as imo it works better.
Rob
Nacra 5.2
OKC, OK
Philip.. Please check to see if you have a set. Would love to have them. Condition?? Price?? Shipping to 94550 in CA Thx Could also use the castings and several other parts that would fit a 5.2 if you have them.. Message here or email to my ... first name.last name@gmail Thx Hal
Hal,
Definitely have a pair of rudders, might have a second set. Pretty sure I have some castings also. I'll get you the condition and price in time so hang in there with me. I'm pretty busy right now and will be till Tuesday.
Philip
Looks like the alum clam cleat is pn CL254
You can also replace the Pivmatic with CL257, works like a charm and has adjustable release.
https://www.clamcleat.com/auto-release-racing-mini.html
Edited by revintage on Mar 18, 2022 - 03:16 PM.
I use it on my monohull.Faster response that the one that came on the Nacra 5.7.