Scott & Tanya Card RV9A build log (N4822C)

Yippee! I found my builder mojo and conquered the brake line! Watson came to help celebrate.
It is Friday, I just had to leave work after lunch to dive back in and resolve the mess I made last night of the aluminum brake line. I finally got it worked out to my satisfaction. Not much to say about it except there is a bit of perservierance involved when things don’t work out quite right the first ‘few’ tries. I must have been excited to win this battle as Watson came out to see what all the excitement was about. It was a good opportunity to show off the handiwork. Sometimes I’m a better dog trainer than airplane builder, but I could have easily made this dog play the piano and sing opera for the hot dogs I was feeding him in order to cooperate :). On the way back inside (after the hot dog treats were all gone), he stopped at the left wheel and thought I should finish the brake line on it as well… I’m ready to build this weekend!

 

  

  

  

  

  

  

  

  

  

  

 

After work, I stopped by Academy sports and picked up a digital fish scale to use to set the breakout force on the nut for the nose gear. It worked great.
Then I moved on to working on forming the aluminum 1/4″ tubing down each main gear leg to the brake calipers. The curly bend at the wheel kicked my butt. I made three attempts all of which I didn’t like. There is nothing particularly difficult about this, but my builder skill mojo simply seemed to not be working this evening. I spent about two hours bending tubing, all of which went directly in the trash. I have spent quite a bit of time looking at other people’s pictures of their brake line bends at the wheel, and I don’t think many of them are planning for what that tube needs to look like for the wheel pant to fit. Surely some people find that surprise much later after flight testing when they try to install the wheel pants and fairings. I don’t know, it just seems like the huge looping bends that you see in people’s initial build pictures won’t cut it in the end. We’ll see. The weekend is upon us, and I think I have enough tubing to give it a couple more shots.

 

  

 

Time to get the nose wheel on it. My first glance at the washers specified for the axle, both under the head of the bolt and nut, didn’t compute. There are three washers that are stacked up on each side of the axle that provide a sliding outside bushing surface and retain the wheel pant bracket. This is one of those little tiny things throughout the build that periodically amazes me that Van actually came up with to begin with. So very simple yet so effective and easy to construct. The wheel is a very tight fit in the fork. It required just a bit of force to spread the fork to get the wheel in. I did the wheel pant bracket modifications as described in the plans. I looked at the instructions for the first time in a long time. There is a lot of useless text on this nose wheel. I kind of set the instructions aside (after reading quickly through them) and just built what I saw. I lifted the front of the fuselage by the engine hook and slid the assembly on with some washers and the nut. Woohoo, rocket science huh.
I need to get a spring scale in order to set the breakout force of the pivot nut and nose wheel fork. Once I’ve done that I can drill the gear leg for another cotter pin. Next on to main brake lines and wheel pants.

 

  

  

  

  

  

 

Another evening, another wheel. This time I tried a little bit different method of drilling the cotter pin hole. First off, I immediately removed the gear leg and put it up on the work bench. Then, instead of marking the hole and grinding the threads first, I simply ran a long #30 drill bit in the hole in the nut as a drill guide. I did that just a bit for a mark. Then took the wheel off and made sure I would still be able to get the nut off. Yep, all good. I put the nut back on, without the wheel and proceeded to use the hole in the nut as a drill guide until I had a real hole started (through the thread). Then I removed the nut to keep from messing up the aluminum too much and continued to drill the hole in the axle. No marking, punching or other grinding shenanigans. This was much better. First side hole drilled slow with a lot of boelube, put the nut back on, indexed the hole (with a drill bit), and did the same on the other side of the axle. Much better results with less hassle.
So now it is all sitting on two main tires! Woohoo! Kinda cool actually. Next we move on to the nose gear. Tanya came out to the garage this evening and her only comment was, “Wow, the airplane got a lot taller.” Yep, I’m glad I waited until the very end to put the wheels on it.

I got all three gear legs lifted and blocked up high enough to get a wheel on one leg at a time. I started with the left main. I installed the wheel after cleaning up the axle enough to get the bearings on. I then threaded on the nut. The next trick is to figure out exactly how tight is “sung”. I decided snug, in this case, meant the nut only tightened by hand and only so much as to eliminate any play in the wheel and cause just a hint of rotational drag in the bearings. That is the tightness of my wheel axle nuts. Ok, so then I used the automatic center punch to mark one top cotter pin hole. Hmmm… It landed directly on top of a thread. I looked at it and thought about this for a few minutes before I made a big fat mess of things. I just barely hit the thread with the center punch, not enough to deform it. I took the nut and wheel back off (no problem spinning the nut back off because I was careful not to hit the thread too hard). More looking and thinking about how I was going to drill the hole on the other side of the axle (bottom). Yeah, I could get under it with a right angle drill or something, but I sensed hours of frustration down that path. Ok, we’re going to pull the gear leg back off of the plane and do this on the bench. Oh yeah, and I’m drilling the holes with an electric drill by hand. I can do this kind of stuff (drilling a hole through a threaded axle) better by hand than in my current drill press. Yeah, I have a little disdain for my old crappy Jet drill press, but I’m about to resolve that :). A big pretty Clausing is in my near future.
So, I jacked the left side up a little more and put a saw horse under the fuselage just in case and pulled the one bolt that holds the gear leg. It slid right out as expected and was up on the bench in just minutes. No need to do all that mess on the floor with limited access. What next? Up on the bench, I clamped it in a drill press vice just for some stability. I then ground down the thread with my punch mark on it. I used a tapered grinding stone in the dremel. This created a flat spot where I could start the drilling and worked like a charm. I turned the drill pretty slow and kept it lubed. I opened the hole up to #30 and touched up the threads a bit with a file. I threaded the nut back on and indexed the hole to mark the other side and repeated the process. It all worked out pretty much as expected with little frustration or misalignments.
Ok, so this all took me a couple of hours to drill two slightly tricky holes. I got things cleaned back up and the gear leg reinstalled with the wheel on it. One down two more to go .