That's drilling, deburring, and dimpling the parts for the left elevator. It is amazing how much more progress you can make once you get past the stupid counterbalance drilling fiasco. In the days since my last post I managed to get the elevator skin and frame parts match drilled, and I am about to finish deburring, dimpling, and countersinking everything.
Here is the elevator all clecoed together adn ready to drill:
A note about the control horn. Apparently many folks have issues with the control horn holes not lining up in the E705 rib and E702 forward spar correctly, and they have to drill additional holes or try to fill in the others that end up a bit oversized. I am pleased to say that I had no such troubles. Everything lined up perfect.
Here is a bit of an oops on my part. Of course it happened because Van's did a lousy job of explaining everything that should be done BEFORE you rivet the E616PP trim tab reinforcement bracket to the bottom of the skin. I should have gone ahead and drilled, dimpled, and installed the nut plates that will hole the access panel for the trim tab servo in place. Now I have to get these holes dimpled somehow and figure out hoe to rivet the nut plates on. I think I will be using my C Frame tool for some of the dimpling/riveting where I cannot get to the holes with a squeezer.
Next - at least I won't have to drill out the rivets this time to drill out and dimple the elevator skin and counterbalance skin for the number 6 screws that I will use to attach the fiberglass tips to the elevators. Did it all ahead of time this time.
Next is another area where folks seem to mess up alot. IN this case the instructions from Van's are clear. This is a blurry pic of the rear elevator spar where the trim tab will be attached to the elevator. You must dimple the bottom flange of this spar and countersink the top flange. The countersink in the top flange is necessary so that the trim tab hinge can be installed flush up against the bottom of the spar flange without being dimpled itsef. You are making a kind of aluminum sandwich as it were, with the elevator skin and trim tab hinge acting as the bread on both sides, and the spar flange stuck inbetween as the peanut butter, jelly, salami, or whatever sandwich fixin you prefer! Pic shows the bottom flange dimpled - still need to countersink the holes on the top.
Next is a pic of a K1100 platenut for a number 6 screw that will hold the trim servo access panel in place on the bottom of the left elevator. Any platenut designated as 1100 means that the center hole with the threads for the screws comes pre-dimpled for the screw head. A platenut designated as 1000 is NOT pre-dimpled. This pic also shows the mounting hole for an AN426AD3-3.5 flush rivet that will attach the plate nut to the skin. The holes for the rivets need to be dimpled in the same manner that the skin is dimpled so that everything lines up for the flush head rivet correctly. Note for builders, I ordered a small radius dimple die from Cleaveland tools some time ago that I have used in several places since. It has a smaller radius than the standard sized die which works great for dimpling the mounting holes of small platenuts. Your only other option is to grind down a set of standard dies yourself,which is also entirely do-able.
This one is a bit blurry but shows the ehole nut plate ready to install:
Next is a pic of the trim tab servo access cover that has also been dimpled for the number 6 screw that will insert into the platenut attached to support bracket. I have also written orientation arrows to help me remember which way the dimples needed to be set.
If you click on the pic to enlargen it you can also see the edges of the platenuts sticking out on the inside of the support bracket on the left side of the pic. I will need to file these down so that they do not interfere with the placement of the trim tab servo mounting brackets that will be attached to the access plate. Lots of detail work goes on here to make certain that the trim system is installed and functioning absolutely perfectly for reasons I have mentioned in previous posts.
Next is a very dark pic. What I am trying to show here is the flat edge of the male #6 screw dimple die that I had to grind down on my grinding wheel just a bit. this die is a bit larger in circumferance than the number 30 or #40 sized dies that I normally use. As such, it just caught the edge of the skin that overlaps the support bracket when I tried to dimple the screw hole in the center. So I flattend out one side just a bit and problem solved.
I don't think I will finish everything before I get to 400 hours total time on the empennage. That would have been a nice round number to pic as a finish goal. Unfortunately there is still a bunch of drilling, prepping, dimpling, priming, riveting, and edge rolling to do, and then comes the mounting to the HS, and drilling out the location of the bolt through the center bearing of the HS and control horns of the elevators, drilling out hinges, and mounting and testing the trim servo and the remaining trim tab assembly. So close but yet so far.
As I mentioned to my friend and fellow builder Steve the other day, you just keep doing the things that need to be done each day, and then one day you have an airplane that needs to be flown. It will happen if you just keep at it. My motivation is very simple - all I do is read the posts from other builders/pilots who have made the journey and finally made it to that coveted first flight. Every single one of them says to keep building, because the end result is absolutely worth every minute and every dime spent to get there.
KPR......
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