The only real issue we are having with the lockdown is kelp... Every time we sail over some kelp the rudder comes up... Of course then it sheds the kelp and we can haul it back down... I guess that's better than dragging the kelp around. Of course I suppose we could avoid the kelp, but there is one heck of a lot of it around Monterey... Just sort of looking around for some method that would haul down the rudder quickly and easily after it comes up....???
Here's another idea I haven't tried yet... What if I used some small diameter bungee cord on the down line?
Seems like that would add a bit of tension to the system and help hold the rudder down... I could tie a knot in
the line at the top where it exits the tiller so that the tension would be "correct". Theoretically the rudder
would still kick up when needed, but it would almost haul itself back down... Of course this is predicated on the
idea that I could find the correct diameter bungee cord... Hmmm? Downsides? Whatcha think?
You can adjust the locking bolt so that it takes more pressure to kick up when sailing in kelp, but remember when coming into the beach it will also take more pressure to release. If sailing on a lake you can stop before the shore and pull on the bottom of the rudders to release if you have done this. Also when the rudder does kick up or release when you hit something in the water it is best, if possible to make sure you use the pull up line and raise the rudder as high as possible and then use the pull down line and pull hard while releasing the pull up line and this way the rudder will have some force when it hits the water and will be easier to relock in position. Trying to relock the rudder when it is still in the water can be a little difficult.
If all components in the rudder system are in good shape, the Prindle rudders are a proven system. The anchor pin and locking pin are straight, the locking bolt is straight and the lip on the lock-bolt is not worn, the springs are not stretched out, the half-round load spreaders are not cracked and decaying, the rudder lines are reaved correctly, the upper and lower rudder sheaves are in good condition and the rudder line is in good condition and is 5/32" low stretch line, all sheaves, upper and lower, have SS spacers, the lock release straps are setup correctly with the sheave and nylon spacer; the system will work. Why try improve on an already proven system?
anchor pin is straight...
locking pin is straight and springs are not stretched out....
the lock release mechanism is setup correctly with sheave and nylon spacer, when you pull on the "up" line, the tension lifts the lock-pin and frees the lock-bolt....
the upper sheaves are in good condition and spin freely, notice the SS washers between sheaves?
the rudder lines are reaved correctly, one on either side of the tiller connector bolt, 1/4" aluminum tubing makes good "T" handles, balls work ok.....
rudder lines are reaved in straight lines to their corresponding sheaves to eliminate binding....
locking bolt is straight, lip is not worn from incorrect alignment on locking pin and half-round load spreaders are in good shape...
Now go sail and stay away from kelp, try sailing further out into the ocean...... π
(PS, many thanks to turbohobo for his outstanding album.. π )
Edited by the-renovator on Apr 10, 2014 - 08:24 AM.
the-renovator wrote: If all components in the rudder system are in good shape, the Prindle rudders are a proven system. The anchor pin and locking pin are straight, the locking bolt is straight and the lip on the lock-bolt is not worn, the springs are not stretched out, the half-round load spreaders are not cracked and decaying, .....
Excellent post and pictures renovator!
It's similar to the "problem" with the pre-1987 rudder casting system on the Hobie 18 with the metal cam.
The system worked perfectly fine while it was in good shape, the problem was after parts started wearing out. (20 years later) Unfortunately that system can't really be fixed once it goes bad. At least the Prindle system can be rebuilt.
____________
Damon Linkous
X2 On renovator's post
Plus, I'd bet you a beer that the lock pin bolt is bent or set too loose
Re: your shock cord idea: I don't see how you could rig up a line that is taught enough to provide downward pressure while the rudders are down yet enough stretch to allow them to kick up? Besides Prindle rudder blades and castings are worth their weight in gold.... don't go drilling holes in them.
Assuming your lock bolts are in good shape ( sometimes they get bent too) you could and should go thru your rudders and replace the line and sheaves/roller/spacers for $20 Before you try to rig up something on you own I'd spend the time to make sure your current system is working properly. The lock bolts are $35 each but I think cost rat has a post on a DIY w/ a SS carriage bolt and a grinder
http://www.murrays.com/mm5/merchant.mvc?Screen=SRCH
Not that I'm the expert on sailing my P16 but my home bay is very shallow and I've found that when a rudder kicks up especially the lee rudder that its very difficult to pull the rudder down against the forward momentum of the water. I sheet out or if I have enough rudder, head up and lock it in.
Hi guys... Back again... I was just wondering if anybody had tried the "bungee (shock) cord on the pulldown line" idea before... I've been through the rudders and they are adjusted correctly... I can pull them down and lock them and they stay as long as I don't hit kelp... Actually, it's sort of a benefit when they kick up in the kelp. The kelp then slides off the rudder instead of getting dragged along... I was just trying to figure out an easier way of pulling them back down when I'm out of the kelp again. I had pretty much given up on the idea in "etraders" photo album (about drilling the holes and adding pins). I agree that the Prindle rudder system is pretty good. It's just that pesky "pulling the rudders back down after they kick up" issue that has me thinking... Soooo, if nobody has tried it before, I may just go ahead and give it a test and see what happens... I can always go back to the standard line that I have if it doesn't work... Who knows? It may revolutionize Prindle rudder technology... Or not!... I'm having delusions of being the Thomas Edison of Prindle catamarans... π π ... I'll let you know how it works out if and when I finally get around to trying it... π
BTW... I too am eternally grateful to Turbohobo for the excellent photos regarding the rudder lines and rudder adjustments... π