Fitting the Stiffeners to the Rudder

I started on the sections of the plans labeled “Building the Rudder” and more specifically, the sub-section “Fitting the Stiffeners to the Rudder”. The rudder is made of thin .016″ aluminum, so Vans uses tiny L-shaped brackets called stiffeners to help support the skin, and keep it from wobbling.  In the kit, these are parts that you have to fabricate a little.  The kit ships with 8 pieces of L-shaped aluminum that you have to trim into the shape of a stiffener.  The plans has the dimensions, and there are some notches in the stock to help you align your cuts.  I used my bandsaw with a metal cutting blade to make the cuts instead of using snips. Here is what the stock looks like:

And here is what it looks like after you rough cut the two stiffeners from one piece of stock:

After we have the stiffeners cut from the stock, we have to trim 7 out of the 8 per side to fit the rudder because it gets smaller towards the top.  In the RV-7, Vans has made this really simple: You cleco on the stiffener and then mark the hole on the forward edge that is the closest to the spar, and then trim off the excess.  It’s important to note in the plans, that we need to leave a 1/4″ edge distance from that hole which I did.  I then used the non-trimmed stiffener as a template to mark the cuts for the end angles.  Repeat this until you get 16 stiffeners and you are good to go!

Next up was to cleco the stiffeners to the skin to match drill.  I started with the left side, marked my stiffeners and skin and then match drilled them right down into a sacrificial piece of particle board to hold everything secure. I did the same to the right side.

After everything is match drilled, I disassembled everything so I could prep the edges and debur the holes.  This is going to take some time, so I only started on the left side stiffeners.  I was able to round off all the corners of the stiffeners, as well as knock down some really rough edges.  All 8 of the left stiffeners are ready for deburring, and then a trip on the scotchbrite wheel to smooth them out.  But, thats work for another session, I have already put in 4 hours tonight cutting out the stiffeners.

Here is all the photos from tonights work:

And the link to the Google Photos: https://goo.gl/photos/1RtwoBeyMD8rGqJo7

Hours Worked: 4
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