4.0 Hours -
Today, I spent four hours working on the plane, but I don’t feel like I have much to show for my work. There are a lot of parts that have to be fabricated for the F-705 bulkhead, and that’s just about all I did today.
The first thing I did was finish making the F-705G angles. It was a good thing that I studied the plans some more because, when I started the parts yesterday, I didn’t realize that one side of the angle had to be shortened. I studied the plans a bit more to make sure I was doing everything that needed to be done, and then it didn’t take me very long to finish these parts.
Next, I started fabricating several parts for the upper part of the F-705 bulkhead. The plans are starting to get a bit vague, basically saying to make and attach several parts. I finding that I now have to pay much closer attention to the drawings than I did with the empennage or wings. After studying the drawings for a while, I started making the F-705J angles, the F-705L shims, and the F-705K plates.
The F-705J angles were relatively easy. I only had to cut some angle stock to the correct length, then mark out a rivet line and drill the holes for the rivets.
The F-705L shims were the easiest parts to make today, and it took me longer to find the stock material than it did to make the shims. Once I located the correct aluminum stock, I just had to cut it to length.
The F-705K plates were a bit more challenging. These had to be cut to length and then they had to be bent down the middle. If I had a bending brake, this would have been easy, but I don’t! First, I tried clamping the part between my work bench and another piece of wood, but, when I tried bending it, the part moved out from the two pieces of wood. Next, I put my back-rivet plate on the bottom of the F-705K, then clamped a board over the top of the part. I then used my hand seamer to bend the part. This worked fairly well, but only because the bend was slight. Yep, the bend only needed to be four degrees!
To bend the F-705K, I sandwiched it between my back rivet plate and a board...then I bent it with my hand seamer.
The bent F-705Ks...4 degrees isn't much!
All of the parts I fabricated today for the F-705 upper assembly.
Once all the parts were made, I had to figure out how to get them all match-drilled to the F-705 channel. At this point, I had to take a break and do some internet research to see how other builders were getting this done. Luckily, it turned out to be fairly easy, but time-consuming nonetheless.
The sequence I ended up using was to first drill the F-705L shims to the F-705F channel. Then, I used the shims to match drill the F-705K plates. With both the shims and the plates match-drilled, I clecoed those to the channel and then clamped the F-705J angle in place and used it to match-drill the channel. A bit confusing, but it worked out well.
First, I drilled the F-705L shim to the F-705F.
Once the shim was drilled, I added the F-705K and back-drilled it.
The F-705F channel with the F-705J shim and F-705K plate.
Finally, I clamped the F-705J angle in place and used its holes to drill the F-705F. It's kind of an odd assembly.
Finally, I countersunk the top of the F-705K plates since those will be riveted to the F-705F channel with flush rivets. Before calling it a day, I also deburred the edges and holes of many of the F-705 bulkhead parts, and I also enlarged several holes for snap bushings.
The last step was to countersink the top of the F-705K plate for flush rivets.
