Small dinghy Rudder Material

Can I use one piece of yellow (Alaska) cedar or mahogany for rudder blade?

 

A single piece of solid wood will likely warp, cup, check or other wise cause trouble. A strip planked blade is a better choice as it doesn't have the issues associate with solid stock. Though I don't recommend it on larger craft a small dinghy (assuming a Nut Shell or similar) will have a lightly loaded rudder blade, so plywood can be used. If you do use plywood, again, not just one piece. Glue two or three pieces together, on top of each other then cut to shape. For example, use 3 layers of 1/4" plywood to make a 3/4" thick blade. For extra strength, cant each plywood layer 12 degrees to the previous layer (cant the port side forward 12, the starboard aft 12 and leave the center layer straight up and down).

 

Thanks Par. I am off looking for some strips to epoxy up somewhat as you noted. I think the mahogany might be available. Will post some pics.

 

Mahogany is nice, but not necessary. I prefer softwood for small boat rudders anyway. They experience less moisture gain then hardwoods, they're lighter and are easier to work. If you do strip plank a blade, make sure you use quarter sawn stock and alternate the grain orientation with every other strip. This eliminates warping and internal stress issues that can arise if most of the grain is facing the same way. Again, if it's a Nut Shell or similar type of dinghy, just glue two pieces of 1/2" plywood together and call it a day.

 

Par, I believe the ply is best here too. The original rudder is ply mahogany and lasted, so, if I can find the right stuff. will do as ply core. Appreciate your knowledgeable help.