NorthWestFloridaBoy
Well-known member
How high should the rudders extend up past the center of my prop? what are the pro's & con's of a single versus dual set up? Thanks guys.
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Good rudder height?
- Thread starter NorthWestFloridaBoy
- Start date
cowboy
Moderator
Hey Lonewolf!
Some say that dual rudders are more responsive, and offer quicker steering action.
Some believe that a big single rudder offers more racking power if your boat is stuck, and you start working the rudder to wiggle your hull free.
I like either. They both do fine.
I prefer a higher rudder mounting, it affords better clearnce when departing a dry bank into water, or if driving over brushy vegetation.
This way the branches or limbs dont spring up behind the boat, and smack the rudder quite so hard.
Higher you go, the more force from the rudder will be applied to your cage for a longer distance. It will need to be strong enough to withstand the rudder forces, and transmit those forces down into the hull.
I've seen boats working the rudder while stuck, and noticed the whole darned cage flexing around.
Makes me duck for cover, cause the cage just might his the prop while running full blast!
For what your gonna do, I'd mount the rudder low. The lower they are, the easier to keep everything lighter and safer.
Down near the height of the transom, then make sure they are tall enough to at least reach the hub of the prop.
Stay cool there Northwest
Some say that dual rudders are more responsive, and offer quicker steering action.
Some believe that a big single rudder offers more racking power if your boat is stuck, and you start working the rudder to wiggle your hull free.
I like either. They both do fine.
I prefer a higher rudder mounting, it affords better clearnce when departing a dry bank into water, or if driving over brushy vegetation.
This way the branches or limbs dont spring up behind the boat, and smack the rudder quite so hard.
Higher you go, the more force from the rudder will be applied to your cage for a longer distance. It will need to be strong enough to withstand the rudder forces, and transmit those forces down into the hull.
I've seen boats working the rudder while stuck, and noticed the whole darned cage flexing around.
Makes me duck for cover, cause the cage just might his the prop while running full blast!
For what your gonna do, I'd mount the rudder low. The lower they are, the easier to keep everything lighter and safer.
Down near the height of the transom, then make sure they are tall enough to at least reach the hub of the prop.
Stay cool there Northwest
NorthWestFloridaBoy
Well-known member
Thanks, I appreciate the info. I'll make them just an inch or two higher than crankshaft center. I'll post some pics tonight of the cage and engine stand on the boat. It's almost done. Oh yeah I almost forgot, how should i construct the rudders to keep them light as possible? keep in mind they only have a 13hp with a 42 inch prop pushin on them.
NorthWestFloridaBoy
Well-known member
A
Anonymous
Guest
Northwest, have you ever built a fabric covered model airplane?
You can take a sheet (s) of guality 1/4" exterior plywood, cut out the shape of the rudders, and then round over all the edges. Then, mark (a paper pattern works good to make them uniform) two or three 'windows' in the rudderes, leaving about 3" all around and between the 'windows', with plenty of material where you intend to attach them. At those points, glue on another piece of the scrap plywood to make a sronger, stiffer mounting point. Bevel all the edges. Same for where your linkage will connect that will operate them.
What you've done so far is lighten the two rudder panels.
Then go buy a new, unbleached 100% cotton bed sheet and fabric cover them just like you would a light airplane. Use Spar urethane varnish. Watch for warping as the fabric tightens while drying. Once they're covered, dried and lightly sanded you can paint them any color you want.
feather
You can take a sheet (s) of guality 1/4" exterior plywood, cut out the shape of the rudders, and then round over all the edges. Then, mark (a paper pattern works good to make them uniform) two or three 'windows' in the rudderes, leaving about 3" all around and between the 'windows', with plenty of material where you intend to attach them. At those points, glue on another piece of the scrap plywood to make a sronger, stiffer mounting point. Bevel all the edges. Same for where your linkage will connect that will operate them.
What you've done so far is lighten the two rudder panels.
Then go buy a new, unbleached 100% cotton bed sheet and fabric cover them just like you would a light airplane. Use Spar urethane varnish. Watch for warping as the fabric tightens while drying. Once they're covered, dried and lightly sanded you can paint them any color you want.
feather
A
Anonymous
Guest
Not anymore, Kevin. I did years ago, and I've helped cover a couple of the full size ones before. I love fabric airplanes.
BF
BF