nofx

Hi all.
I'm currently getting some new rudders machined up for my boat. The existing ones are 2mm thick, Can I make the new ones 3mm without too many problems?
Thanks.

OLD_SLOW and in the WAY

studies on rudder shapes pretty much dictate tha they be a wedge shape with a square back edge this creates an air pocket behind it at speed and not allowing the water to be dragged causing drag. but i think the rudders are more like 3/16 to 1/4" thick.
one rudder i saw is from a guy that ran in a turtle infested pond and he used a large lockback knife blade for a rudder just so the very hardware unfriendly turtles didnt swim away unscathed

pompebled

The size of your rudderblade is linked to the size of your boat.

My 50 cm mono-hull has a 2mm thick wedgeshaped aluminium blade (which I recently swapped for a 1,5mm stainless steel one, my 65 cm mono-hull has a 4mm wedgeshaped alu blade, the ones with a waterpickup in it are 5-6mm thick.

Regards, Jan.

nofx

the size of my boat is 52 inches. She's a pretty big girl....

pompebled

I'd go with something like 35-40mm wide, 150mm deep (depending on how deep it sits under the prop/hull) wedgeshaped, 4-6mm thick in aluminium, in steel you may go thinner, but not so thin that it can flex under load.

Assuming we're talking about a rudder behind the transom and a surface piercing drive.

Please post some pics of your boat.

Regards, Jan.