Flying Dutchman Dinghy Rudder

[DionK (Rafnar Hellas)]

I’m here struggling to design the rudder of my Flying Dutchman dinghy. I’ve downloaded the nessesary NACA profile and design the outline of the rudder. I’m now trying to figure out how I’m going to model the tip of the rudder Anyone with prior experience in foils?

FD-RUDDER_RevB.3dm (55.7 KB)

[martinsiegrist]

Rudder design

Most of the rudder I design use the following method quite successfully: draw a leading edge curve with tip radius. draw a trailing edge curve. import my favorite NACA thickness section and scale appropriately for a tip and root chord. sweep two using the the leading and trailing edge curves as the guides and root and tip chords as those to be swept along the leading and trailing edges. I’ve included a couple of simple screen shots for your perusal; it’s something I did in 5 minutes for the p…

You’ll find a few more examples in this forum. Try the search function looking for ‘wingtip’ or ‘rudder’

[DionK (Rafnar Hellas)]

[DionK (Rafnar Hellas)]

Same subject different design.

[martinsiegrist]

Also if you want any specific help, it is always good to share your Rhino file…

[Stratosfear]

[DionK (Rafnar Hellas)]

That’s an interesting one! How did you achieve that?

[Stratosfear]

I start with surface extruding the cross section shape. I’ll use split surface along isocurves, Shrink Yes. Then I split back the leading the trailing edge blends. Then Surface blend the tip and split it back to make room for the corner Surface blends. Curve dup the corner round edges. Curve Pull back them on to the primary surface in Teal. Then use those curves to trim the edges. Then use Surface match preserve iso direction to match/join the corner round edges to the primary surface. Watch Sky’s youtube channel Thirtysixverts to learn this method.