They keep creeping aft a little at a time and create an awful weather helm .
It seems that the line slips in the cleat . I replace line and cleat and the problem remains .Is there a trick I should know ?
What did you replace the line with? Most nacra sailors on my beach have had success with fat, soft lines like West marine's "stay-set" braid. Fat lines get less stuck in the casting when you pull down underway, say some.
I upgraded the cleats to "genuwine" aluminum Clamcleats, and very low stretch (8% @ swl) line, with no further problems.
The hotshot on our beach does something he calls powerlocking the rudders. Flip up the "pivmatic" set the line in the Clamcleat, then pull the pivmatic down - locking that rudder in tight to the casting and locking the line tight to the cleat. One advantage is, you don't SLAM the rudder into your casting or hull.
Do check your hull for rudder impact, BTW.
Hope this helps!
Ed
I'm using stiff, narrow, non-stretch line (don't know the brand) for my rudder pull down. Sounds like this is not the norm. Work great, though. They NEVER slip, even on my original 1983 cam cleats, yet release easily. As Ed indicated, the smaller line does occassionally get pinched in the casing when pulling the rudders down, although with the right technique it is rarely (never) a problem.
By the way, Ed sent me a nice tretise on rerigging the rudder shock cords a while back--if you need any info on that. His technique worked great for me.
Eric-
Did you "upgrade" to the Pivmatic cams or do you have the original, riveted on aluminum camcleats? I found the issue was twofold- the little SS shackle Performance riveted onto the plastic camcleats resulted in rivets partway down in the cleats so smaller line (or trying to pull line tightly into) would not "hold" and the plastic cleat "teeth" wore out quickly- especially on hard line-
I removed the SS shackles, cut a slot in the bottom of the cleat (so it didn't interfere with the "teeth") and ran a thin line through tied in a loop to keep the rudder down line in place, used really soft cover line that was gripped well and replaced the cleats fairly often. I found when I tried replacing the plastic cleats w/ aluminum (on the Pivmatic) the Pivmatic would "trip" BUT the line would not "release" completely- This was okay IF that was enough "clearance" for whatever you hit, but if what you "hit" was the beach this was NOT enough and it would basically "tear" the Pivmatic. I DID find though that even if the Pivmatic rear "hole" (where the pin goes through it and the tiller arm) were ripped out they would still work - BUT when they "trip" they end up trailing behind the boat!
Kirt
Hi Kurt!
I worried about the clamcleat not releasing; so I made sure when I mounted the shackle, to mount it well forward; so that with the pivmatic in the up position, the line is pulled out of the clamcleat. Sometimes, my thin, stiff line 'hooks' around the shackle and won't easily feed; that's why I'm changing to fat, soft line - also so it doesn't jam in the casting.
BTW I found the shackle rivets to be a problem too, in the plastic. The aluminum ones I drilled so deep the rivets were partly in the base of the clamcleat.
Ed
Kirt-
I do have a pivmatic system--don't really know if it is stock but it was present when I bought my well-used boat. I'll decribe it: pull down line goes through an aluminum cam cleat that is attached to a partial fiberglass tube that grasps the tiller arm and hinges on it by a clevis pin. The tube pops off the tiller if the rudder grounds, releasing it to raise smartly due to the shock cord tension.
My system works perfectly. Sounds like the original posters problem may be a mismatch between the line and cam cleat sizes since its is a creeping release of the rudders.