Quick and dirty rudder prototype
Greetings,
I’ve been tinkering in the shed the last few days, and have come up with an interesting rudder concept. I was inspired to start this by Chris’ renderings in SRIR thread. The design itself was inspired by about 8 different rudder designs which went through the “design spiral”.
It has a geometry which allows the rudder to kind of fold up, with the tiller on the deck and the blade tucked up under the cross beam. This feature was a lucky accident really, resulting from some shortcuts and lazy builder decisions.
Features include:
-Kicks up both ways
-Stores in a safe and “spray avoiding” way which also keeps the weight out of the bow.
-Lightweight with minimum parts (but a bit more rope than I’d like)
-Easy and quick to retract (on shore anyway 😉 )
Downside: Yet more knots to tie when going for a sail. This point can be improved on I’m sure.
This is just cobbled together in the easiest way I could think of (which led to the folding, nice). The tube is aluminium, scavenged from a zimmer frame. Everything else is also scrap I had lying around.
Some more picures can be found on my website, which also has info and a couple of videos of my boat.
-Thomas
What does the line lashed to the tiller do?
What does the line lashed to the tiller do?
It looks like it rotates the rudder once it’s been pulled up, so there’s no need to go climbing around the boat during a shunt. You pull in and cleat the lines for the “then” rudder and uncleat the line to the “now” rudder and you’re all set with no fussing about.
It’s well thought out. I like it.
Very nice, Thomas. It’s so cool to see stuff evolve on the forum. I really dig your interpretation!
Maybe there’s a way to get your anti torque line a bit lower? That will reduce the load on it a bit.
Keep us posted on how they work, ok?
Chris
Maybe there’s a way to get your anti torque line a bit lower? That will reduce the load on it a bit.
I doubt there’s much load on them to begin with, and the nice thing about where they are now is that if a rudder strikes something while moving that bowline knot should slip up along the bend and let the rudder kick up before the shock load gets big enough to break something.
What does the line lashed to the tiller do?
I see that the video clearly shows what this line does.
http://www.youtube.com/watch?v=iSfrVIqo9iQ
Nice concept, very good potential for a simpler rudder system.
Cool!
If it is hard to keep that torque line down with the right presure, you could also consider an auto release cleat ( http://www.duckworksbbs.com/ProductDetails.asp?ProductCode=SD-002570 ).
I like it better as it is thou!
Looking forwards to see it in action!
Cheers
Cool!
If it is hard to keep that torque line down with the right presure, you could also consider an auto release cleat ( http://www.duckworksbbs.com/ProductDetails.asp?ProductCode=SD-002570 ).
I like it better as it is thou!Looking forwards to see it in action!
Cheers
Certainly a consideration. I recently saw this trick as well, I’ll quote Todd Bradshaw:
Clam Cleats are a rectangular block and have V-shaped teeth, lined up in a row to form sort of a long, toothy valley or trench. As you pull harder on the line, it sinks down, deeper into the trench and this increases the grip on the line. Obviously, if you cleat a centerboard or rudder blade, accidentally hit something, and pulling on the line just makes it grip harder, you might do some serious damage to the blade, rudder housing or hull. This is the danger of having cleated downhauls on rudders and centerboards, yet a rudder that tends to ride up at high speed is extremely annoying.
What they had done was to use the plastic Clam Cleats (some are plastic, some aluminum) and take a drill bit just slightly bigger in diameter than the hold-down line. Then they drilled a fore and aft, horizontal channel all the way through the cleat at the very bottom of the trench (the point at the bottom of the V-shaped teeth). In normal use the cleats work like any other Clam Cleat, with the V-shaped teeth gripping the line. If you hit something hard enough though, instead of locking everything up, the line gets pulled deeper into the cleat until it finally pops into the drilled channel - and at that point it can run free and release the blade to kick up.
Preferably I’d remove the torque line altogether and see how that works. The weather is starting to turn so hopefully I’ll be out on the water soon to mess around with it.
-Thomas