I'm still futzing around with that Pacific Catamaran 19 I got a while back. I'm still a couple of weeks from the water, but I'm down to only one real ughknown: the rudders.
I took everything apart and rebuilt them as far as I can go. My wife made up a set of shim washers out of some Delrin sheet we had lying around:
I used these to shim the blades in their housings, and the tiller bars to the crossbar. There's practically no slop in the rudder/tiller system now. I can't wait to try this out on the water!
The tiller arms on the P-Cat are made from teak. This is a first for me. But the teak cleaned up nicely, and took a good finish with teak oil. Since I'm planning to sail year 'round in salt water, I figure I'll have to re-clean and treat every six months or so. Gauging by how much I used to restore these after sitting out for ten years, the bottle I got should last me... well... probably 'till I die. It doesn't take much.
There are two tiller extensions. Again, this is a first for me. I had a single adjustable stick on my Prindle. I might eventually go that route on this boat, but for now the dual extensions work fine. I'm not 100% happy with the universal joints where they attach to the tiller crossbar, but it's workable. If in doubt I'll find or make something else. (I haven't machined stainless in a while, so that might be a fun exercise.)
The part that has me stumped is the pivot action of the blades themselves. I can kinda see how the blades are held down, but not exactly. Here's what one of the rudder assemblies looks like:
The housing is an aluminum casting. There's a stainless sheet metal weldment bolted on top to take the tiller arm. It's held in place with what looks like a pair of 1/4"-20 hex head bolts and nuts. The nuts are peened to the bolts in three places, so they're not coming off. The gudgeon pins are cast in place (pretty typical, from what I can tell) and there's a little locking tab riveted just below the upper gudgeon pin. When the rudder is installed on the boat, the lock is twisted to the up position. This locks the rudder assembly onto the boat.
The blade pivots on a 5/16" bolt. There are two other holes in the blade. The first is a 1/8" hole directly above the pivot. This passes through the housing and through the blade. Each blade/housing has this hole in a slightly different position, so there's a good chance this was added by one of the boat's owners. A 1/8" stainless pin fits through this, so I'm guessing this was added as a rudder lock.
The second hole is a 3/8" hole below the rudder housing. When I bought the boat, the rudder housing assemblies had a 3/8"x3" wooden dowel stuck through each of the holes with a bungee cord wrapped around it:
The bungee was over ten years old, and was completely shot. But I can see that with new bungee cord it would do an ok job of holding the blades down. It would also probably do an ok job of holding the blades up:
I THINK this would work, but it doesn't give me the same warm fuzzy feeling as the cam lock system on the Hobie or the spring detent system on the Prindle. Those resulted in a very positive, very definite lock on the rudders. This feels more like it's just encouraging the rudders to be in one position or the other. (My guess is this is why a previous owner might have wanted a more positive lock, hence the 1/8" holes!)
Before I cut new bungee for this, I wanted to run it by the group as a sanity check. Does this look at all reasonable? Does anyone know what the rudders on the P-Cat were supposed to look like?
Thanks,
Tom
--
Tom Benedict
Island of Hawaii
P-Cat 18 / Sail# 361 / HA 7633 H / "Smilodon"
--
