Building a New Rudder

[Ben Diss]

I just took possesion of an EC12 and decided to clean up the rudder a bit. I removed it and first realized that it was heavy. I didn't weight it, but I was very surprised. I took it to the belt sander to remove the bowed side and found that it was made out of poured resin.




I figured a good project for the week would be to make a new one. So, I read all I could online and reread Wells' stuff and set off about making a new rudder. I had considered glass over foam, but I'm not sure that's allowed. Since I didn't have any foam in the shop anyway I decided to make it out of balsa and glass.

I'm a complete newbie to boats, so please chime in if you see something not quite right here.

I started by cutting a piece of balsa.

[Ben Diss]

In order to ensure that leading edge is true and the shaft is perfectly centered I started with a 1/2" dowel. I chucked it up in my mini-lathe and started a hole.




I used a long bit and drilled 3.5" into the dowel.

[Ben Diss]

Next I needed to shaped the LE of the rudder to accept the dowel. I took a piece of 1/2" tube and sharpened one end. I used this to rough shape the groove.




Next, I wrapped 220 grit sandpaper around the dowel and completed the groove.

[Ben Diss]

I cut a slot into the side of the dowel to insert the rudder shaft. I then drilled a hole into the rudder to accept the shaft.




After a little more trimming I mixed up some epoxy and glass fibers to joined the dowel to the balsa.

[Ben Diss]

That's it for tonight. I've got about 3 hours into this now. I'll try and tackle a little more tomorrow.

-Ben

[Pink66]

Ben, that's a great start for the rudder. Sounds a lot like what I did when I made my plugs for my rudder molds. One thing to watch for as you develop the final shape of the rudder. You will find the top of the keel is narrower than the bottom. You may have to add some fairing compound to the bottom so you have an even transition from keel to rudder across the entire length.

Mark

[PaulP]

Ben,
The post is Great. A big help to members.

To those curious about the posted pictures, Ben is doing it by putting the pictures on his server site then referring to them in the code he posts with the message.

We will be able to post pictures in the near future.

Paul P

[Ben Diss]

Wow! You're right. I wouldn't have thought to even look. It's about .15" difference between the top and bottom of the keel.

[Ben Diss]

I fitted the rudder to the hull. Here I've marked up the bottom so I can trim it to size.




After reading Mark's comment and measuring, I decided to laminate some balsa to my existing rudder so I can make it wide enough on the bottom. I'll let the glue dry tonight and work on it this weekend.

Day 2: 1/2 hour.

[Ben Diss]

Here it is after shaping. Just a little cleanup to do and I'll glass it.

[Doug Wotring]

be sure to shape the top of the rudder where it meets the hull

[Ben Diss]

Thanks Doug. Almost forgot. I'm not sure how deep to make the recess, but I think it looks good.

Here I've got the rudder in the bag. I cut two mylars and I'm using 2 oz cloth.

[Ben Diss]

Got a little more work done over the weekend and this evening. I found that my glass work ws real crummy and I ended up sanding off most of the glass and filling imperfections. Finally, Sunday night I was able to reglass it correctly. I spent about 6 hours on this over the weekend.

Tonight, when I came home from work I sanded off the excess epoxy and did some final shaping.

[Ben Diss]

Here it is in my "oven" while letting the second round of primer dry. I'll try and shoot color tomorrow. Time spent: 1 hour.

[kahle67]

Ben,

It may be just the images, but that rudder looks to be a little long. Is it 3.5" or less?

R Kahle