Well, that didn't work as expected.

After the work last night and posting the pictures, a builder with obviously more knowledge than me said "I believe  you may have overlooked a major issue related to bending the tempered aluminum tubing - spring back.  It is impossible to form the tubing over an exact pattern. The tubing must be bent well past the desired shape, held for a few seconds for a "set", then allowed to spring back."

Whoops.

So much for the "quick, easy, and rewarding" promise from the kit manufacturer about the build. It seems to me that you need quite a significant about of metal-working experience and engineering training.  That I don't have.  The problem is the instructions are not as detailed as hoped and have some "there are several way to do this and no one right way" statements.  Now, I don't want to seem like I am degrading the manufacturer because, by all accounts and brief personal experience, he is responsive and will talk things over on the phone.  However, the thousands of calls I envision for every bend have me embarrassed, so I'm trying to not call him whenever possible.

Long story short, as much as I desperately want to do this project, I'm starting to have thoughts that I don't have the engineering qualifications required for this project.  I can drill and clean holes, rivet sheet, safety-wire bolts, and many other things related to aircraft.  But, there is a lot more fabrication in this project than expected.

Still, I'm pushing forward with the practice rudder.  I gradually formed the rudder frame with a small series of had bends outside the form.  Below are the pictures of the work done tonight.  I'm not all that happy with the work, as I want something that will carry me in the air to be built as precise as possible.  Ironically, the advice I keep getting is from builders telling me to not worry:

"This is not an F18, so do not drive yourself crazy with minute precision"
"We are building airplanes....not heart valves"
"Perfection is the enemy of completion"
"Airplanes, and in particular AA aircraft, are simple (crude?) machines
where precision is only required in a few areas"
"Keep it simple light and strong 'enough' !"
And my favorite:"you're building an aeroplane......not a pocket watch! "

I get it, I really do.  Micrometer precision on metal bends aren't practical.  However, when you have an office job and no formal A&P or engineering training, I have no real idea of what mistakes are safe to work with and what ones compromise safety (in some instances). That makes me paranoid, especially without step-by-step instructions.

That said, here are tonight's pictures from the practice rudder build.  Please comment and be critical if you see something wrong.  I need it.

The final rudder frame, not a precise as I wanted.

Marking the rudder spar for cutting

Using the marks to drill a 1/2" hole for the rudder frame slot

Testing the hole with a 1/2" drill bit after using a step-bit to drill the hold and deburring it.

Cut along the line, which turned out to cause problems

Here is that problem demonstrated with a 1/2" drill bit:  the walls of the slot don't go up high enough to attach a rivet.

Used the tube notcher to drill out the hole deeper to give more metal area on the sides for rivets.

Test fit works, so the spar then went to the sander to smooth and debur before drilling and riveting.

Used a rubber mallet to hammer the sides flush against the rudder frame.

After the test fit, the spar and the frame are marked and drilled with a #30 bit for the rivets.

The finished rivets.  Not too happy with the finish (the term "wonky" comes to mind).

My biggest concern:  the structural integrity of the rivets with the gap in between the frame tube and the spar walls. Of all these photos, this is the one I REALLY want comments on.

The bottom of the spar was drilled as instructed with a #30 hole in the forward side and a 1/2" hole on the rear for the rudder frame.



The fit was nice and tight after trimming the rudder frame.

This is the fit inside the spar.  The plans call for screwing into wooden dowels placed inside the rudder frame tube.  I'm not really understanding that part, and there were no dowels in the kit.  PLEASE HELP!  What do I do here?



Next, the same #30 in the front and 1/2" hole on the rear for the middle support strut/tube/whatever it is called...



Test fit looks good after notching the end of the strut, deburring, and sanding the cuts.

Next, cutting and fabricating the gussets for the left and right of the support strut.  These were mage with 0.032 sheet, marked and trimmed to match the curve of the rudder. Made two, one for each side.

The finished and riveted gusset for the middle support strut.

Top view of the riveted gussets.

The other side...

Finally, where I stopped tonight. I need some help understanding exactly how the middle and bottom tubes are to be attached to the spar, so that is the next step.

 Well, there it is.  It seems to be coming together, but I am really having doubts about my ability to finish this.  Comment and tell me what you think.

Planning time = 2.5 hours
(again, this is the practice rudder)