Elliptical Rudder

[jpaulroberts]

OK. I too am interested in transforming my 1987 rudder into an elliptical one. I have printed Ron Hill's article with the photos, but on the Tech-notes CD the overlay drawing is so small and fuzzy, I can not read any of the dimensions. How can a I get better drawing that I can scale up? Thanks much, Jerry

[dave davis]

If you send me your US mailing address, I will send you my sketch of the New Rudder. My address is 1174 Solana Dr. Mountain View, CA 94040. Or send it by Email at  Davis_707@yahoo.com
If someone has a good scanner, maybe this sketch will be good enough to put up on our MB

[Ted Pounds]

Jerry,

Ron's rudder design is for a wing keel model.  I see you have a fin.  The new rudder design for the fin is quite different though I suspect it would still be an improvement.

[Ron Hill]

Jerry : I did publish a copy of the elliptical overlay design for the fin keel rudder in the Mainsheet tech notes.  
When I get home in mid June, I can look and see if I have the original overlay that I could send you, but as I recall there were no measurements.  Think that you'd be better off with Dave Davis's offer.

Interesting, You are the first person to ask about modifying a fin keel rudder.  With the additional 9" of depth (over the wing rudder) are you having a steerage problem?  

[jpaulroberts]

Ted, you're right, mine is a fin keel. I take it that it is still a desirable upgrade but it looks like it will be harder to do since is not just wider (front to back) but also much deeper. Has anyone out there tried the mod for the fin keel?
Thanks, Jerry

[Ron Hill]

Jerry : The reason that people with a wing keel are so interested in going to the elliptical rudder is very simple - - there wasn't/isn't enough wing  rudder surface (MKI) to stop the uncontrollable rounding up into the wind!!!

I do believe that your fin keel rudder being 9 inches deeper than the MKI wing rudder might be OK.  Remember that the MKII with the elliptical rudder compensates for the added surface BEHIND the pivot point by having a 44 or 46 inch wheel.  All MKIs only have a 32 inch wheel.  Bigger in your case, might not be better!!

You'd better consider if you really want to do that type mod and if you really need it!!  A few thoughts to ponder.  

[Tom Glennon]

I have the standard rig/fin keel on my boat, and I couldn't be more pleased with the feel and balance of my boat.  I previously had a tall rig/fin keel on my catalina 30, which had weather helm that was a bear over 18Kts.... I would double reef the main to balance her out.  The 34 is just so balanced and feels like rack & pinion steering!  Perhaps the problem is in the sails or the trim.   By the way, I recently installed the new Garhauer traveler cars... 5/1 (6/1?) What a wonderful difference that makes for main control!

[Mark G]

This is our first season on a 91 wing keel, and today was the first time I experienced the rounding up problem. But that was with an inexperienced sailor at the helm who was pinching in a puff that logged almost 28 knots.  We reefed and had no trouble holding high 6s on the GPS with wind in the high teens and low 20s. We also could have blown the traveler to leeward or rolled in the 135 a bit.

Unless you're racing hard, do you really need the new rudder? Winds have been in the 20s our last four times out with no problems. The 34 - wing keel and all - is a DREAM compared to my 30 when the wind pipes up.