I wanted to lay up a thin layer of glass over the rivets holding the hinge material to the gear leg fairings. I used a couple of strips of the lightest cloth I had on hand and covered them in some Dacron (which is what you see here). I’ll do the other side of these soon and then I can put a thin coat of filler on the fairings.
I wrapped up the hinge on the other gear leg. I’m probably going to end up shortening these since they’re a bit longer than necessary. I need to fabricate the clamping pads at the top of the fairings, and then I can align them to the longitudinal axis of the plane.
The clouds lifted enough in the afternoon that I could take the plane up for another flight. I took the opportunity to calibrate the AOA system. On the SkyView, this is done by doing a series of stalls in various flight configurations and hitting a button on the EFIS each time. I also took the plane up to 8,000 ft to measure the true airspeed. I’m still slow because the wheel pants and gear leg fairings are not installed, but I saw 162 kts. I expect to be near 175 kts after the fairings are installed.
I also intentionally ran my right tank dry in flight so that I can do the final fuel gauge calculation. The SkyView system annunciated “fuel pressure” just a second or two before the engine started stumbling. I switched tanks and hit the boost pump, and the engine surged back to life within 3-4 seconds. The experience was very different than when I’ve run a tank dry in my Bonanza. In the Bonanza, the engine power winds smoothly down with no surging or stuttering. After changing tanks, the power winds smoothly back up. In the RV, the power loss was much more abrupt and there was quite a bit of stumbling before power was smoothly restored.
I wasn’t able to spend much time at the hangar today, but I did get down there for a bit in the afternoon. The winds were way too strong to fly (at least until I get more practice in the plane), but I did get a chance to resume work on the gear leg fairings. I had previously trimmed them to size and put strips of tape along the aft edge as reference points to ensure they’re straight. I then clamped the trailing edge with some cleco clamps and drilled the hinges to the inside of the fairing. After countersinking, I removed the hinge and deburred it. I used some of the G/flex epoxy from West Systems to bond the hinge halves to the inside of the fairing and then riveted into place with some soft rivets. I only had time to do the right fairing today, but hopefully I can knock out the other one tomorrow.
I had been planning on fabricating some jacking points for a while now. Even though I’m going to lift the plane by the engine mount using the shop crane I bought, I need something under the wings to keep the plane from swinging. Since I fabricated aircraft jacks awhile ago, using them to support the wings seemed like the best plan. I bought some 1″ galvanized pipe caps and drilled them for a 3/8″ bolt. I then inserted a 2″ long 3/8″-16 bolt through and tightened it down with a washer and nut. This is screwed all the way down to the stop I installed in the wing tie-down point. I might trim about 1/4″ off the bolt to reduce the bending load a little further.
The cap just fits over the end of the ram on the jack. It has just enough room to move around that I can insert it over the ram without having to be perfectly aligned with it.
My buddy Andre stopped by the hangar this morning to help me remove the canopy one last time.
I inadvertently used the wrong weatherstripping on the flange at the forward edge. It was too thick, and the canopy skin kept catching on it and was tearing it off. After Jenn and I reinstalled the canopy the last time, I found the correct weatherstripping in a box, so I decided to swap it before first flight. Unfortunately, after Andre and I removed the canopy, I could no longer find it, so I have some new weatherstripping on order.
I didn’t get any pictures of it, but I lubricated all of the bearings on the plane. There are nearly three dozen of them, and many are exposed to the elements. I’m using a product called DriSlide. It wicks into the bearing and dries, leaving behind a film of molybdenum disulfide. This film is extremely slippery, but because it’s dry, it doesn’t attract dust or dirt, is highly resistant to water, and prevents rust and corrosion. I’m also using it on the sliding pins in the brake calipers to keep dirt from sticking to them.
After wrapping that up, I installed the wingtips. I used some DriSlide on the hinge pins and they slipped in effortlessly.
I reinstalled the alternator with the washers in front of the pivot shaft. I checked the alignment, and it looks perfect. I adjusted the tension so that I could turn the alternator pulley with 13 ft-lbs of torque (with the pulley slipping on the belt), but couldn’t turn the pulley with 11 ft-lbs of torque.
After fully inspecting all of the controls under the seats, I installed the forward center section cover, fuel pump cover, spar covers, seat pans and tunnel cover and screwed everything down.
The DAR mentioned that he doesn’t like Van’s design for the flap pushrod attachment since the rod could come off if the rod end fails. Every other rod end on the plane is either captured by the surrounding attach point or has an AN970 washer to keep the rod end together in case of bearing failure. The failure of a rod end can be a catastrophic failure since a split flap condition can cause a violent rolling motion. Since full flaps are usually used on final approach when low and slow, a failure here could be fatal. By switching to a regular rod end from the ball joint linkage supplied in the kit, you can prevent the joint from ever coming apart.
Fortunately, my friend Greg had already warned me that the DAR would like the see these parts upgraded, so I had the parts in hand. I also upgraded the pushrod from the one I made to the one sold by Avery Tools. I still need to adjust the pushrod length to get the flaps back into alignment with the ailerons, but I’m much happier with this arrangement.
Since my CG ended up farther back than I was hoping, I’ve been looking for ways to move it forward. I purchased the Bell tailwheel fork a long time ago since I really dislike the Van’s design. I didn’t realize at the time how much heavier it was though. While researching other options, I found that the tailwheel fork sold by JDAir was even lighter than Van’s. I haven’t measured for myself yet, but they told me that I should save about 1 pound from the Bell fork. This doesn’t sound like much, but with an arm of over 249″, this change alone will move the CG forward by over 0.15″. The fork comes plain or powder coated in either gloss white or gloss black, but I previously powder coated all of my tailwheel components in matte black, so I ordered it plain so that I could match the finish. I stopped by the TechShop earlier today and smoothed out all of the edges and then sandblasted the areas that will be powder coated. That produces a nice textured finish that the powder coat will stick to nicely.
I applied the powder coat and then baked it in the oven for about 20 minutes at 350º.
My big goal for the day was to compute the weight and balance. To do that, I needed to have the plane ready for flight.
In preparation for reinstalling the canopy (hopefully for the last time), I applied a strip of UHMW tape under the leading edge. This will help the flange slide over the weatherstripping without catching and dragging on it.
I sanded down the epoxy I applied the other night and painted on a few coats of primer. There are a few pinholes I need to deal with, but this is good enough for first flight.
Between coats of primer, I fixed the pitot and angle of attack tubing. I had previously made these connections in the wing root, but that was a mistake since there’s no room to ever service them. I had planned on running new lines down the conduit, but I realized I could use the same lines if I added a couple of additional connectors in the wing. I disconnected the tubing at the pitot tube and slid it inboard inside the wing enough that I could pull the excess through the holes in the fuselage. These fittings will now be trivial to service if that is ever necessary.
I then cut the lines in the wing and took some longer pieces and ran them from the pitot tube to these fittings. This is better anyway since I can disconnect the tubing here and pull the pitot tube out of the mount. This is looking up into the inspection port just inboard of the pitot mast. With the way the lines were previously run, pulling the pitot tube out of the mount required disconnecting the lines right at the top of the mount. That wasn’t too painful, but reinstalling the pitot tube was a real pain since it required hooking up the tubing entirely by feel. This way, the fittings are easy to inspect and verify correct installation.
I got my replacement fuel pump from Andair, so I ran down to the hangar tonight to install it. I pulled the old pump out and removed the fuel filter. Since I’ve pulled fuel from both tanks, I wanted to clean the filter to remove any debris that might have made its way into the tank or fuel lines during construction.
Despite my best efforts to keep the tanks clean and sealed and clean the fuel lines before installation, there was a surprising amount of junk in the fuel filter. I rinsed everything in a few ounces of gasoline. It looked like mostly dust and small sandy particles, but there were a couple of small metal particles mixed in. It’s good to get all of this out of the fuel filter before the first flight.
I lubricated the o-ring, safety wired the filter and reinstalled it on the pump.
Here’s the completed pump assembly with wires cut to length and a molex connector installed.
Finally, I reinstalled it in the plane and re-torqued all of the fittings.
Next, I installed the wingtip so I could get an idea how the light was aimed. It looks pretty high, but I’ll need to level the plane to be sure. I’m pretty happy with how bright this is. Here’s the hangar across the way with the light on.
And here it is with the light off.
To get a better idea how the light is aimed, I pulled the plane out into the taxiway and put the tail up on my chair to get the fuselage level and then turned the light on.
I adjusted the light until the beam was roughly level. You can see it does a pretty good job of lighting up the taxiway.
I walked to the far end of the taxiway to get an idea how much light was making it down there. The picture doesn’t really capture it well, but it was uncomfortable to look directly at the light, even from this far away.
This picture of the shadows cast by my legs gives a pretty good idea how well the far end of the taxiway is lit up.
Finally, I resumed work on the canopy fairing. I started with sanding the fairing down to be flush with the two layers of electrical tape and got the overall shape where I wanted it. Next, I removed the upper layer of tape and sanded the fairing down again to be flush with the remaining tape.
After taping over the exposed parts of the canopy bubble, I mixed up some epoxy with black pigment and applied a sealer coat on the fairing. After this cures, I’ll sand it down and apply a coat of primer.
In preparation for wrapping up the canopy and getting it reinstalled, I applied the weather stripping to the flange and trimmed it to fit. I also recently received my avionics cover from Flightline Interiors, so I installed the supplied velcro and tested the fit. It works great and should hopefully help me keep my avionics dry.
Next up, I started working through the list of issues that were found in the inspection yesterday. I safety wired both brakes since I don’t think there is any reason to remove the wheels now before first flight. I also checked the two bolts identified yesterday as having too many threads showing, and they’re both fine.
No pictures tonight, but I spent a few hours at the hangar knocking various tasks off of the to-do list. First, I trimmed the excess sealant around the leading edge of the canopy and put a little bit more where there were a couple of small holes Next, I finished torquing the vent line fittings in the cabin and zip tied the fuel sender coax to it on the right side.
I tried the modified tool and it works pretty well. I’m going to do a little more adjustment on it so that it doesn’t hit the steel bracket and clears the universal rivet heads.
I wasn’t quite getting the aileron throw I wanted, so I switched to the smaller bushing I had.
Adjusting the aileron bolt required dropping the flaps. I could almost remove the rod end that screws into the flap, but the pushrod hit the edge of the hole just before the bolt could slip out. I sanded the hole a little bit larger, but kept it inside the black line I drew that showed where the flap overlap sits. This covers the hole when the flaps are up.
In preparation for installing the weatherstripping that will seal the forward edge of the canopy, I fabricated a couple of strips to span the gap in the flange. This way I can have a continuous strip of the weatherstripping across the entire edge.
Afterward, I used some Sikaflex to seal up all of the gaps.
Sealing around the canopy hinge is the most tricky, but I think this will do a pretty good job.
