I made an emergency rudder for my Santana 3030 from closed cell foam and a mess of 'glass. It was terribly oversized, insanely heavy but it did steer the boat. I sold it to a couple of guys who were taking a 50-footer to Hawaii in the Pac Cup.
In 2007 I made a foam core rudder from a NACA 0015 blank from Flying Foam - https://flyingfoam.com/
I'm no whizbang composite dude, so I just put on layer of knytex - http://www.tapplastics.com/product/f...nytex_x_mat/91 in TAP medium-set marine epoxy and then a layer of unidirectional glass cloth over the top of that, oriented vertically along the rudder blade. I didn't vacuum it, I just laid out a mess of sandbags on the garage floor, wrapped the whole thing in wax paper.....that's right, wax paper.... and then put more sandbags on top. A day and half later I took it all apart. If I was doing it again, I'd use actual peel ply instead of wax paper. That would save a LOT of sanding.
The thing was pretty heavy, a lot heavier than a foam/epoxy/carbon, vacuum-bagged rudder, but I could stand on it and sort-of jump up and down on it, so I figured it was pretty strong. It also cost 1/8th of what a custom rudder would cost. The blade wasn't *THAT* much work, but the cassette was a PITA. I made the cassette from wood and sections of door skins. Door skins will bend, with patience and encouragement. The skins were glued/screwed in the front to a shaped piece of 2 x 4. Three layers were epoxied together to make a 3/8ths inch cassette. In the back they were glassed over with mutliple layers of tape. Then I wrapped the thing with a few winds of unidirectional carbon in epoxy, just where the gudgeons were going to go. My welding dude in Redwood City made some custom gudgeons for me. They got attached and voila.
This isn't my cassette, mine swept back to a "V" shape at the back, but you get the idea. It was basically like this, adding in the carbon fiber straps. This picture is from Kame Richards site.
http://www.sailmaker.com/articles/e_...es/er_cas1.jpg
I tested it in the Bay, sailing from Coyote Point to Berkeley and back again with the main rudder tied off and just using the emergency rudder. It loaded up a lot and sure it wasn't as fair as a pro-job but it worked.
Honest truth is that my next emergency rudder will be purchased from Rudder Craft.
https://ruddercraft.com/
They make a NACA 0012 section, milled polyethylene rudder that will sit just fine on the back end of my boat. It's sized for something like a Catalina 25, and the price is great. It will, however, require patience to deploy as it doesn't come with a cassette.
https://ruddercraft.com/index.php?ro...&product_id=98
Last edited by AlanH; 12-31-2016 at 05:45 PM.
1968 Selmer Series 9 B-flat and A clarinets
1962 Buesher "Aristocrat" tenor saxophone
Piper One Design 24, Hull #35; "Alpha"