aluminum rudder?

Moderator: GreenLake

aluminum rudder?

Postby DavidOates8011 » Fri Oct 01, 2021 10:02 pm

Has anyone made an aluminum rudder & rudder head? This would save weight over my rudder from D&R that must be solid fiberglass. I've seen discussion on an alum. rudder head. The by-laws only regulate the side profile, not the thickness or foil.
If so, any advice on the rudder thickness, how to include the down & uphaul? Does it perform any different?
David Oates
DS1, #1924, year 1965, 'Survivor'
San Antonio, TX
DavidOates8011
 
Posts: 26
Joined: Thu Feb 05, 2015 10:07 pm
Location: San Antonio, TX

Re: aluminum rudder?

Postby GreenLake » Fri Oct 01, 2021 10:53 pm

David, I know for sure that there are discussions on aluminum rudder heads here. Several people have done them. I'm not sure how you can find them the quickest other than searching for "site:forum.daysailer.org aluminum rudder head" (without the quotes) in your favorite search engine.

I've not seen anyone make an aluminum rudder blade before. The problem is that to get best performance you want a NACA profile at least 1" thick. Unless you can manufacture a hollow blade from aluminum, that gets heavier than you might like, and shaping wouldn't be fun.

Why not do a wooden blade, sealed in epoxy and with just a bit of glass for scratch protection (more where you tend to hit things...). And do an aluminum head for that.

A wooden blade has some buoyancy, but it's not too bad: you're not seriously loading the pintles and gudgeons in the opposite direction. Especially not with some weight in tiller, head and fittings. But that buoyancy means, you don't have the weight dragging down the stern; it's basically neutral.

A profiled rudder should perform somewhat better. When I did mine, it was hard to tell. Definitely not worse than before ;). You may need another boat to carefully trial against in like conditions to note anything - the kind of thing that wins races but isn't observable in cruising.

I don't know about up and downhaul. Don't have either. There are some clever solutions out there and some you find discussed here. A while back, though.
~ green ~ lake ~ ~
GreenLake
 
Posts: 6482
Joined: Mon Jun 18, 2007 3:54 am

Re: aluminum rudder?

Postby DavidOates8011 » Sat Oct 02, 2021 3:26 pm

Greenlake,

I'll stick with my rudder blade & make a new rudder head from alum. That will lighten up a little. Thanks for the advice.
David Oates
DS1, #1924, year 1965, 'Survivor'
San Antonio, TX
DavidOates8011
 
Posts: 26
Joined: Thu Feb 05, 2015 10:07 pm
Location: San Antonio, TX

Re: aluminum rudder?

Postby GreenLake » Sun Oct 03, 2021 12:25 am

One thing to consider for the design of your rudder head and the routing of the downhaul is to make sure that the tiller can still swing up, even when your are under way.
~ green ~ lake ~ ~
GreenLake
 
Posts: 6482
Joined: Mon Jun 18, 2007 3:54 am


Return to Racing/Performance

Who is online

Users browsing this forum: No registered users and 2 guests

cron