Month: February 2020

Today I final drilled a few holes in the aft bulkheads.

Most of the holes were #30, but a couple were 1/4 inch, which I did on the drill press. Then I took the pieces apart and deburred the drilled holes.

I skipped ahead a little, as I’m waiting on a drill block to help with some of the drilling where alignment is critical. I worked on the F-01410 bulkhead; deburred, stepped-drilled a systems hole, fluted and dimpled the F-01410 bulkhead. Then I straightened and final drilled the 1/4 in holes in the F-01410C, then clecoed it ready for final drilling.

Then I clecoed the F-01411 Bulkhead ready for final drilling.

These two bulkheads will hold the horizontal stabilizer onto the fuselage, so there is a lot of reinforcing here.

I put in a couple of hours tonight deburring parts. Not much to report. It’s a straightforward process, but can be a bit slow going, especially where there are corners. I almost finished deburring the aft three bulkheads, but started falling alseep, so calling it for today. Of course most of these parts will need final drilling and then more deburring, but that is a relatively quick process.

My 3/8 countersink arrived today, so I in stalled it in my modified cage and calibrated it on some scrap. Using the bench press, I countersunk the 8 holes in these two stops.

I’m really happy with how these turned out.

I spent a couple of hours today deburring parts for the aft two bulkheads. I also finished shaping the rudder stops.

Deburring was straightforward, except for the flanges at the bottom on the bulkhead, where there is a very small gap. I picked up some Emory cloth to squeeze in between the tighter spots, otherwise I used files and edge deburring tools. I still need to final drill some of the holes, but I’m waiting on a drill block that will help ensure the holes are exactly perpendicular, since some of them receive fine-tolerance bolts that hold the vertical stabilizer.

Finishing the rudder stops involved some more filing. I clamped my vixen file to the bench and this helped ensure a straight edge.

I also modified a countersink cage to allow me to countersink the rudder stops. There is very little clearance between the flange and the hole. Also on-order is a 3/8 inch countersink bit to allow enough clearance (typically they are 1/2 inch).

I spent a couple of hours this week working on fabricating the horizontal Stabilizer attach bar support angle, and the rudder stops. I used a combination of the band saw, vixen file, and small files to get the shape as close as possible to the drawings. I’m still not completely done, but these are pretty close. The vixen file has been great at getting a nice clean flat surface, it makes the job much easier. Once these are final shape, I need to countersink some of the holes, then they will be ready to be primed.

I spent some time cleaning and reorganizing the garage, including building a couple of storage racks for the elevators. I stored them out of the way and then put some loose zip ties on to keep them from falling off.

Then it was time to start on the aft fuselage, and I was able to complete the first few steps, separating parts and straightening a couple of stiffeners.

Several of these pieces were snipped or hack-sawed into separate pieces, including the plastic rudder cable guides. In the picture you can see the open crate in the background. I’ve been storing the skins and stringers in there for months, and it’s good to start pulling them out.

I trimmed and final drilled a few pieces, and then straightened these doublers. Here you can see the “before and after” where one piece is straightened and one is how it arrived. These bend as a result of the hole punching process. Straightening involves putting them in the vice, putting some tension on the part, then pounding with a rubber mallet. The majority of time is spent fine tuning, and having some patience is important.