It's time to cut out the rudder head. It has an arc on the end around which the rudder blade with a matching arc will rotate. My skills with the jig saw are a bit lacking and the attachment I have for the Rotozip doesn't open enough to make an arc 6&3/4" in diameter. So I cut a piece of scrap plywood, cut a hole in it the size of the Rotozip (fortunately I had a bit that fit it perfectly), cut out a piece big enough for the adjustment knob to also fit, and gave it a try. Worked wonderfully!
Here's the jig:
And the two matching halves to the rudder head:
I had wondered whether the bit would survive. I had previously broken several in trying to learn how the Rotozip worked. They seem to snap off easily. I ordered some new bits and decided it was worth a try. I was able to set the bit in it's deepest setting, meaning the tool was close to the board. I turned it on with no contact with the board and eased into it. Worked! I believe what snaps the bits is binding it in the board when you turn it on. Anyway: presto! I have a rudder head.
I took a breakfast break and went back out. I needed to shape the rudder blade. I Used the same jib to cut the curve in the blade. It is supposed to have a 1/8" larger arc which is the diameter of the bit. The rudder used the inside of the arc and the blade uses the outside. There you have it. I drove a nail through the hole in the head and lined up the blade with it. Clamped it down and then put the zip jig nail through the same hole. Easy peasy.
After cutting the arc I had to cut a couple more angles and then plane the foil shape. Not perfect but it'll have to do.
I went down after church tonight to do a little epoxy work. I wanted to laminate the rudder head and glass the blade. Here's the result of an hour and a half's work.
Not sure whether I'm going to put the rudder "cheeks" on just yet. It calls for 1/4" ply and I haven't torn into any of it yet. Will want to use scraps to do it. We'll see.
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