Cowling Piano Hinge

The hinge holds the upper cowling to the firewall. To remove the cowling, you pull the hinge pin out and the cowling can then be removed.

I have struggled with this seemingly easy step for a couple weeks. The instructions appear to have an error in them. The index holes that they call for do not line up with the holes in the firewall flanges and the top skin.

I also was concerned that the holes in the hinge that they call for in the instructions will be too close to the edge of the hinge. I have seen two different tolerances for edge distance: 2 diameters and 1.5 diameters (from the center of the hole to the edge). In this case, that would mean an edge distance of 3/8″ or 9/64″. My first attempt was a little shy of that smaller distance. Perhaps a more experienced builder would have ignored this and continued on but it bugged me.

While doing research on this topic I found Stu’s Aircraft Factory on Youtube. He built an RV-8. He has lots of interesting building tips. He mentioned in one video that the piano hinge supplied by Van’s is MS20257-3 and is susceptible to having broken knuckles (eyelets) over time. He recommended substituting MS20001P-3 extruded aluminum hinge. About 4x more expensive, but I decided to go with it since I had several broken knuckles on the RV-8 and RV-10 that I had owned.

I am confident in saying he was right and the added expense was worth it. Look at the difference between the two parts in the following pictures.

This is the original part from Van’s, an MS20257-3. Each knuckle is just formed by rolling the edge.
Here is the more expensive MS20001P-3 extruded part. You can see each knuckle is one much more substantial piece.

I spent about an hour putting the hinge on and match drilling it. I am happy with the result so far.

The Finish Kit has Arrived

I picked it up at the ABF freight terminal this afternoon. No damage to the box. I found out that a friend of mine is the loading dock foreman there so he helped me get this BIG box onto the trailer (it just fit on the 5×10 U-Haul trailer). The only problem is that I had no way to unload it at the house other than to open it and remove all the parts. On perhaps the most windy day of the year I had packing paper flying everywhere.

Now the canopy and the back window plexi-glass are safely upstairs in the house where it is reasonably warm. The rest of the stuff is downstairs ready to be inventoried. The shipping container ended it’s life at the county dump.

There were a few things on back order, but now I will be able to continue building for awhile.

Things are Starting to Ship!

The Whirlwind propeller arrived today and it is beautiful. I opened the box just to look at it despite not being able to do anything with it for at least three months.

Meanwhile, I got news that the finish kit will arrive at the freight terminal next Friday. It weighs 411 lbs and is 98″ x 49″ x 30″. The shipping charges were $770.00. If I had had it delivered to the house it would have cost an additional $70. I wasn’t sure when I was going to be home so I decided to just have it shipped to the terminal and then I can rent a trailer to go get it.

The panel is still being built at SteinAir. According to Nick, the panel has been cut and painted, but the technicians still have 4 to 5 panels in front of it. Still guessing it will be mid-April.

Flaps and Upper Forward Fuselage

Jon and I got a lot done today. We finished up routing the brake lines. We fixed a couple pop rivets that I screwed up (last post). We installed the flap actuation system. We installed the Forward Upper Fuselage. We pulled several cables from the tail cone forward.

Soon it will be time to remove it from the rotisserie so we can start on some firewall things that are currently unreachable. The rotisserie makes working on the airplane so much easier.

Total time: 12 hours (Jon 7, Me 5).

This is the flap actuation system. The motor is surprisingly small. The orange cable supplies power to the baggage compartment light.
The upper forward fuselage is the structure that holds the canopy and the instrument panel. It is riveted to the firewall and to both sides of the fuselage. It also has a center bracket that connects it to the tunnel. In this picture you can see the can of paint I used to hold one of the NACA air vents in place while the ProSeal dries.


I was putting in a small number of AACQ4-6 rivets to hold the plastic guides for the rudder cables. Apparently, my pop rivet tool was not tightly against the side of the tunnel and I ended up with a bad rivet. Normally, not a big deal — just take it out and put a new one in. Except I had exactly zero AACQ4-6 rivets left. Oh well, a call to Van’s to order $8 worth of rivets and a small assortment of other stuff I needed…

Moving the Project to its New Home

Yup, we decided to move it to my basement so that I could more easily work on it whenever I had some free time. The challenge was getting it into the basement. I determined that taking a window out would allow me to move it into an unused space in the basement that from this point forward will be referred to as “The Airplane Factory”.

Don’t worry, I will be able to get it out in a few months when it is ready for the engine and landing gear.