Canted rudders

[Night Sailor]

I've noticed in pictures of several boats with twin rudders, all not made in the USA, that the rudders are not vertical as in the Macgregors, but are canted outboard at the bottom, ostensibly to increase rudder control when the boat is heeled. Anyone know why Roger hasn't done that too? Or why there is no mention of anyone on the forum doing this with thier Macs? Why do it, or why not do it?

[Frank C]

I wouldn't want to expend the effort, mainly because it's heavily dependent upon the rudder brackets. You'd need to do some major modifying to the brackets, and I'm not sure how much value it might add. And when the rudders are raised, it seems the transom entry would be completely blocked??

[delevi]

The foil shape of the custom rudders I had made expose much more rudder area aft compared to the stock rudders. That's one solution. The problem I have is that the angle of attachement for the rudder downhaul lines is different, which causes them to trail a bit aft, no matter how tight the line is secured. My solution was to drill holes in the area where the rudders are fully down, and secure them with quck pins, through those holes & brackets. They're dead locked and vertical with a good deal of area aft, much more than stock. It is a bit of an extra effort to insert and remove the pins when you need to raise/lower the rudders, but the performance gain is well worth it.

Leon

[Frank C]

Leon,
I snapped this when experimenting with Phosphoric solution for cleaning the hull ...
but it also shows the hold-down padeye for a 26X rudder. You can also see the hold-down line leading upwards toward the rudder hole drilled for the line. On the X-boat, drilling this rudder hole so it's adjacent to the padeye would prevent the rudder from trailing, at all ... unless I'm missing something about the new rudders.

I guess the 26M's hold-down arrangement isn't as easy to manage? I'm asking because I'm thinking of ordering similar larger rudders as upgrade for my X-boat.

[delevi]

Frank,

I can't quite make out your setup from this picture, but here is what I think is going on with my rudders. The downhaul line, which keeps the rudder in place when deployed is the same distance from the stopper and the same distance from the attachment point as the stock rudder. I measure this agnausium and can't find any difference. What I believe is the problem is that the stock rudder presents more wetted area forward, under tha transom, compared to the IDA rudders. The attachment on the IDA rudder is adjacent to the leading edge, while with the stock ruddeers, it's a few incehs aft of that point. The distance is the same compared to the angle where the line entry is going into the hull, but with a few inches of extra area going forward, the center of effort appears to be different. I hope this is clear. Anyway, after hours of setting and testing, the new IDA rudder position, though close to perfectly vertical, still allows the rudders to trail aft while the boat moves forward. The only solution I can come up with, which I actually implemented was to use the extra holes in the brackets, adjacent to the holes for the screws which hold the rudders to the brackets (used for the pins for trailering.) I 'm not sure if the X has these holes. I drileld through the rudders, through those second set of holes in the brackets to insert quick pins. This will hold the rudders in palce firmly, without trailing aft. A bit of an extra effort, but in my case, I disconnect the engine anyway, so it's a few more seconds to lock the rudders in place with those pins. If this is not clear, I guess we'll have to go sailing again so you can check it out first hand. Despite the bit of extra effort, the differnce in performance is phenomenal, and well worth the small compromise. I believe the added drag is neglegable, far less than dragging a prop through the water, and quite insignifcant when comapred to avoiding those annoying roundups. So far, even with my short time experimenting with these new rudders, I love them. And this is while they were allowd to trail aft. I believe the difference will be even greater, now that they will be locked in place with the pins.

Leon