This post is all about fixing mistakes...its painful to bare my soul to my readers sometimes. :) But as I always say, I cant be the only one making these kinds of silly mistakes...so this will let you know, you're not alone.
First though, as I get ramped up for FWF work, I wanted to do a good cleaning of the shop and reposition Wablosa for better access and lighting on the engine. The dust from doing composite work has been making me crazy! So...for the first time in her life, Wablosa seen the light of day. I wheeled her out into the driveway so I could hose down the garage. Very cool to see her "out" and "mobile"...I gotta say, another one of those times I was happy to have a taildragger. It was a piece of cake moving her around by myself and I was amazed how light she was. Anyway, these are some cool pics.
I spun her around 180 degrees and put her back in nose first. I have much better lighting on that end of the shop. Eventually I will take the emp back off so I can have some extra room...the shop is getting cozy though.
I'm trying to wrap up the bulk of work that I have left on the empennage, while its on, so I can disassemble it and store it until I move to the hangar.
One of my outstanding items was to fix my elevators. When I match drilled my elevator horns...EXACTLY as Van's instructs you on my workbench...somehow, I got them mis-matched. Once I mounted them on the plane, in a neutral position, one side is sticking up about 3/16". I did some research on VAF and Van's will tell you not to worry about it. Its not going to affect the flying characteristics of the plane to any large degree and no one will ever see it unless your elevators are in their neutral position. Since, messing with controls is not a trivial thing...I have been debating this for quite a while...do I fix it or leave it?
Ultimately I decided, I couldn't live with it as is. First, it will affect the flying characteristics of the plane...even if its minor, I'm not in favor of that. Second, I would always know...and although my plane is not going to be perfect by any means, this issue would bug me to no end....crooked airplanes don't fly with me! (pun intended) ;)
So ok...how to fix it? Again...research the forums, see what others have done. No sense reinventing the wheel. Weld it closed and re-drill is probably the best option....less weight, cleaner solution. I don't have a welder and I don't plan to send my delicate elevator to a welder so that wasn't an option for me. The other way to do it is to rivet a piece of steel inside the horn and, again, re-drill. I bought a piece of 0.063" 4130 steel...which matches the elevator horn material, sometimes called "Chromoly". Don't just buy garden variety mild steel (probably 1020) or heaven forbid, aluminum, from Home Depot for this. 4130 steel is considerably stronger and harder than 1020, which is important for your control surface attach points.
First step, oversize the offending hole. Don't try to turn it into an oval or figure eight...not worth the headache even it you could pull it off, this hole means nothing anymore...its now a clearance hole. Your scabbed-on piece will have the important hole now. Just open it up just enough to give you the room to get the elevators lined up. I upsized just a little at a time until I got it just right.
Here is my 0.063" thick 4130 steel sheet that I ordered...
Again, carefully cut it to size to fit inside the elevator horn. We want to leverage the return flanges on the horns to help minimize shear forces in our attachment rivets. Although, this is overkill as the structural cherry max rivets will be able to withstand the shear forces...I like to double down on stuff like this...."belt and suspenders."
Once I got it trimmed up nicely...including radius-ing the edges to fit inside the horn...I match drilled my rivet holes. I then put it back on the airplane and attempted to drill it and get it right this time. I used the same procedure as before that Van's recommends...the only difference is this time its on the plane, not a work bench.
Bam! Came out just like it was supposed to this time. I don't have a pic...but just trust me, they are lined up nicely now. I ordered some structural cherry max rivets...threw a coat of primer on the steel...and when I receive my rivets I'll rivet this puppy together and declare victory. I was happy I did this. My advice to you...obviously try to avoid this pitfall. I would match drill it in place, on the airplane, not a bench. Just my take...
Onto one of my other &*#%-ups. Fixing the cracked plexi. As you know from my previous post, I got a nice spider crack in my rear plexi right above the roll bar. I stop drilled the cracks and now its time to fill those holes. I bought some Weld-on #16 (I think JB Weld #3 would also work)...put some tape on the back side and dabbed some in the holes to seal them up. I will then sand it down...add filler as needed to get it smooth and then paint over the top. You'll never know its there. As long as I got 'em all and don't get more cracks later, I should be ok.
I decided to do some custom inspection/access panels for my aft fuse. These will go around the elevator horns and match up with my empennage fairing. More on this later...but here is a pic of my pattern.
Thanks for sharing, that looks great!
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