Moving onto the rudder

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The fin only needs four gussets glued on, I will do that next time I mix up some glue. Time to start building the rudder.

Before the rudder can be built I need to cut off the excess of the fin and rudder spar. This is necessary to establish a straight line so the top rudder rib is installed straight. In the picture above the red level is keeping the top of fin and rudder rib straight.

Cutting the top of the fin off, for me, is a little difficult due to the curve of the nose. To establish a straight reference to make the cut I clamped two straight blocks to each side of the rib.

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This was not so simple to hold and cut in my cramped workshop. So I clamped the fin to my workbench.

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That took just a few minutes.

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After a few minutes of sanding it looks pretty good.

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Once that was done I started cutting some RS-17 to length for the rudder ribs as seen in the image at the top of this post.

The ribs need to be tapered towards the trailing edge. Keeping everything straight while the glue dries might be a challenge with the tapered ribs. To make this easier I am going to use a method I picked up from building R/C models. One of the first models I built was a Sig Kobra, it had washout built into the wing. To make it easy to assemble and keep the washout accurate the back of each wing rib had a little tab to keep the rib at the proper height. Found a picture here that shows this. I plan to leave a little tab on the back of the rudder ribs when I cut them, I will be sure to take some pictures when I start cutting them.

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