Rudder build for Bad Kitty

[Guest]

And here's the first one almost finished, just a bit of a tidy up, tape the leading edge and done! [attachment=0]Rudder finished.JPG[/attachment]

 

Old rudders with 50mm 2205 stainless stocks & bronze tillers, blades made of foam & eglass = total weight 28kg each.

 

Carbon stock, blade & tiller = 7.1kg each.

 

Thanks to;

 

Nina, Clever Fox Engineering. Engineering and nearly all of the work.

Jamie Logan, Custom Marine. Machining and technical help.

Richard Edlin, mould making & boatbuilding.

Willy, bugger all labour, cockad a few things up which meant more work for the first 3, did buy the lunches, beer & Mt Gay.

 

Gooday 'B-K' - Well done to the whole team. Sure does save some weight. May I ask why you didn't go for a more advanced rudder blade shape that may have reduced surface area thus drag & weight & have created less drag at less angle when turning the boat??? Sure does look the 'full monte' !! Nice job. Ciao, james OH & thanks for sharing with all of us !!!!

[BelowPAR 0]

Thanks for the info !

[Bad Kitty 252]

(quote]

 

Gooday 'B-K' - Well done to the whole team. Sure does save some weight. May I ask why you didn't go for a more advanced rudder blade shape that may have reduced surface area thus drag & weight & have created less drag at less angle when turning the boat??? Sure does look the 'full monte' !! Nice job. Ciao, james OH & thanks for sharing with all of us !!!!

 

Hi SR, well it's the same shape as the old rudders which work well on the boat. It's an offshore cruising boat with a reasonably big rig & long foot on the main, so I do like a good grip when the wind is up & aft of the beam.

The high aspect shapes you are talking about are high performance, but do stall more easily from my limited understanding of it all.

And the boat speed is usually max of 15-18 knots, not a 25 knot sort of drag to worry about.