Aileron hinges and install

With the ailerons complete, it was time to install them onto the wings!

First step was to make sure the trailing edge of the aileron wing pockets were perfectly straight. I did this with a straight edge and sanding block...


Next was to notch out 0.2" where the hinges will go. This is so that the hinge can get tucked between the wing and aileron.


I then marked where the bolts will go so we could match-drill the hinges to the wings... I also made a 45-deg bevel on the fiberglass so that the hinge could get tucked a further 20 thou... this helps get the aileron as close to the wing as possible and keep the gap between the aileron and the wing to a minimum.

Happy with the hinge placement, we used hot-glue gun to "tack" the hinges in place. Hot glue gun is a lot easier to clean up than bondo as it peels right off.



Since the hot glue is not strong enough to hold the hinge for match-drilling, my buddy is helping me press the hinge towards the wing while I match drilled through from the other side...



Taaa-daaaa!!! Hinge holes drilled! (first with a #30 pilot, then opened up to #12 drill bit)...


Here's a good shot of that 45-degree bevel I mentioned earlier... this really helps the hinge tuck in for a minimal gap...


Before installing the nutplates, I wanted to make sure the AN525-10R8 screws all fit well, so I installed the hinges using regular nuts.. and double-checked to make sure all hinges were perfectly in-line! All looked great!




 I then installed the nutplates onto the hinges... I explained in detail how to do this when installing my rudders.. click on this link for those details...



With the nutplates installed, I bolted the hinges onto the wings...


This is one of those moments where the plans say something like "go ahead and install the ailerons to the hinges".... and you're left trying to figure out how the heck to do it!

First of all, I needed a way to get the hinges to stay up so that I can tack them to the ailerons.


I cut a few "L" shapes from plastic cards...


And taped them to the bottom of the hinge. This created a "spring" so that the hinge would stay up and allow me to press the aileron down onto it...


I did this for the inboard and outboard hinges only for now... you'll see why in a minute...


I then brought the aileron into place... and positioned it exactly where I wanted it...


I then raised it up a tad...


Raising the aileron a bit created a small space between the aileron and the hinge which allowed me to inject 3 small blobs of hot glue in there...


I then pressed the aileron back down onto the hinge... while making sure the aileron was flush with all surfaces... and held it there until the hot glue gun cured...


Another shot showing me pressing the aileron down onto the hinge while the hot glue gun cured...


Small blobs of hot glue gun between the hinge and aileron...


I then repeated this for the outboard hinge...


I tested the aileron travel by hinging the aileron back and forth... when I was happy with the aileron travel, I removed the AN525-10R8 bolts, and brought the aileron to my bench... placed a few extra blobs of hot glue gun on the bottom to make sure it was properly tacked in place. I then marked all the rivet holes per plans. (NOTE: the plans show you the rivet pattern but do not show which side of the inboard hinge is the inboard or outboard end. There is an extra rivet on one end, and I came to find from other builders that the extra rivet goes on the inboard side (to reinforce the hinge onto the A2 bracket and A10 tube).


I also marked the rivet patterns for the middle and outboard hinges...


But what size drill to use? First we need to know what size rivet to use.. which the plans don't say! However, CP #32, under "builder hints" says the following:

Clarification: Anywhere on the airframe where you are installing nut-plates, on hinges,
access panel, use 3/32" diameter flush pop rivets, or solid aluminum rivets. When
installing aileron hinges onto the ailerons, use 1/8" round head pop rivets (Avex
1601-0410, or cherry MSP 43) rudder hinges are installed into the rudder using flush pop
rivets (Avex 1604-0412 or cherry MSC 43). CS2 elevator hinges are installed on the
elevator using flush pop rivets (Avex 1604-04 or cherry MSC 43).

So since I will be using MSP-43 rivets, I used a #30 drill bit...


After drilling all 48 holes (YES, 48 holes!! 10 for the inboard hinge, 7 for the middle hinge and 7 for the outboard hinge... that's 24... but remember, there are TWO ailerons!).. I then removed the hinges, removed all the hot glue gun blobs, sanded the surfaces and prepped everything for a nice glass flox to aluminum bond!


I also dulled up the hinge surfaces to prep them for flox bonding...


The plans say "make sure not to get flox in the hinge hoops"... so I put grease inside the hoops to keep any flox out!


I then painted plain epoxy onto the ailerons where the hinges will go...



And also painted plain epoxy onto the hinge backs before applying a thin coat of wet flox...



 With all hinges prepped, it was time to install the hinges to the ailerons!



I used MSP-43 rivets as clecos (positioning pins) to install the hinge exactly where it needed to be. Notice I didn't place ALL the rivets in for now... this was to give me room to squeeze the rivet tool.. and to focus on installing all hinges before the flox started to cure... after all hinges were in, I went back and installed all remaining rivets.






Notice there is one rivet on the inboard end of the aileron that is exposed...


Here is a close-up of the exposed rivet... just above the A10 tube...


Since I had flox leftover, I added a bit to the corner and sealed the exposed rivet head to protect it from weather...



After all rivets were installed, I used a flat toothpick to remove as much excess flox as possible..



 I then let the hinges cure...


The next day, I removed all the grease from the hoops using q-tips... and reinstalled the hinge halves with the nutplates...



I installed the ailerons on with AN525-10R8 screws and AN960-10L washers...



PERFECT FIT!!!!



I then hinged the aileron back and forth... I noticed a little binding on the edges, but used a metal file to take care of it... page 19-14 in the plans specifies the min-max tolerances on all aileron edges...




Super happy with how the ailerons turned out! The gaps are perfect!!! I do need to file the edges a bit more per plans.. as CP #43 "builder hints" warns us that the ailerons may be nice and free on the ground, but when in flight, the gap might shrink and cause the aileron to bind!


And there you have it! Ailerons are installed!!!




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