Fuselage - Cabin

2006-10-21 - Installing the landing gear mounts (RV-7A only). (5.0 Hrs).

Spent time this morning finishing up the flap assembly, for now. I say for now, because we need to attach the wings before we can finish the the flap assembly. The things that I still needed to do included using the hand seamer on the F-760 covers, and final install and torquing of the bearing blocks. In the process, I found some more AN3-20A bolts in another bottle, so I guess Van didn't short me after all (sorry Van). Before I started working on things this morning I wanted to remove the seat floors and see if my 3/8" nutdriver was under there--it was.

After finishing the flaps, I started working on the landing gear mounts, since I am building and RV-7EH. This presented a bit of a problem, because the fuselage stand was bolted to the fuselage through the wing bolt holes. I figured the fuselage stands needed to be removed, because they would be in the way. This meant that I would need to suspend the fuselage while I removed the stands from both sides of the wing spar.

A few months ago, I saw a neat way to suspend the fuselage on Jeff's website. I didn't want to go to Home Depot to buy an eye bolt, so I fabricated my own lifting hook, using parts that I had on hand. This took an inordinate amount of time, and I probably would have been better off if I had just gone to HD and bought an eyebolt and a few big washers. Nonetheless, I spend most of the session fabricating my device.

When I was done, I figured out that I probably could have just put the front of the fuselage on a saw horse, removed the fuse stands, and lowered the fuselage down by hand--hind sight is 20/20. Besides, I was home alone this weekend, and I didn't want to hurt my back. Yeah, right. We all know I just wanted to build the hoist attachment.

Found my 3/8" nutdriver, right where I thought it might be, under the seats. The nutdriver was still attached to the bolt that goes through the rear spar. That would have been a scarry noise on the first flight!
Inserted the AN3-20A bolts from the FWD side and torqued them down. Probably need to apply some finger nail polish, I mean, torque seal, to the nuts.
Next step in the plans is to install the landing gear mounts. Here's all the parts. I already did most of the fitting of the WD-721 landing gear supports when the fuse was upside down, but there's still a few things to do.
Since my fuselage support system uses the wing bolt holes and blocks the holes for WD-721, I need to raise the fuse and remove the supports.
I constructed a hoist attachment, inspired by Jeff Bordelon's website. I'll show you how this works in just a minute.
Here's the bottom side.
The two outside boards go in first. The tape holds them in place.
The center piece is slid between the two boards and attached to the hoist. This pushes the two outer boards up against the spar web, and the washers on the bottom of the center piece are stopped by the outer boards, so the fuselage can be lifted. Unfortunately, with the fuse lifted by the hoist, it is way too unstable to work on. I still need a way to support the fuselage after the supports are removed.
The front of the fuselage is sitting on a 1x8 supported by two plastic milk boxes. I'm not so sure if the milk boxes (actually cheap imitation milk boxes) are strong enough for me to sit in the fuselage, but I can at least install the landing gear mounts. This may be a good height to begin with, I'll let you know.
Match drilled the right gear leg to WD-721-R, using a 5/16" drill bit. I don't have a 0.311" drill bit, so per the plans, 5/16" is the closest I can get.

Note, I was not able to run the drill bit all the way through the gear leg. Even with cutting fluid, the drill bit and gear leg got really hot. The drill bit tended to stall about 1/4" in on both sides. The gear leg does not need much drilling in order to get the bolt through, so I match-driled one side, then I inserted the bolt half-way in that side, and match-drilled the other side. The bolt is a tight fit, but that's what we want. Deburred all holes when I was done drilling.