Posts Tagged F-706 bulkhead
Aft Fuselage Clecoed (2/11/12)
Posted by Ethan Jacoby in Aft Fuselage, Construction, Fuselage on February 11, 2012
2.5 Hours -
I started off by trimming the ends of the J-channels. On the lower four J-channels, both ends require trimming. However, I’m still not sure on the upper two, so those will have to wait. The actual trimming was completed by drilling a hole in the bend on the channel, enlarging the hole to the desired radius with a step-drill, and then finishing the cut with a Dremel and cut-off disc.
Once the J-channels were finished, I slid them back into place on the aft fuselage assembly. I then when to work clecoing the F-706 bulkhead to the aft fuselage. This took a little time since the F-706 assembly is a little bulky, and it took a little brute force to get things to line up at times.
With the F-706 in place at the front, I turned my attention to the rear and slid the F-710 bulkhead into place. The plans say to put the F-710 in last, but it is obvious that it would be a real pain to get the bulkhead in after the tail assembly is in place. With the F-710 loosely in place, I next started trying to cleco the F-779/F-711/F-712 assembly to the rest of the aft fuselage. At first, I couldn’t get the assembly to fit, but I quickly realized that the J-channels were interfering with the F-712 bulkhead. To fix this, I had to remove the tail assembly and trim a little more off the ends of the J-channels.
Once the J-channels were trimmed a bit better, it still took a little work to get the tail assembly to fit into place, but, eventually, I got it. I was able to cleco everything in the tail section except for one side of the F-711 bulkhead. The flanges of the bulkhead aren’t bent quite right. So, I’ll have to remove this part and re-bend the flanges so that they better match the angle of the fuselage side skin. Hopefully, this will take care of my fit problem.

A side view of the aft fuselage. The upper J-channels are just sitting on the top for storage...that's not their actually positioning.

The flanges of the F-711 bulkhead still need some work. I'll have to remove the bulkhead and bend the flanges to better match the angle of the skin.
F-706 Again And Still Not Done (1/18/12)
Posted by Ethan Jacoby in Bulkheads, Construction, Fuselage on January 18, 2012
1.5 Hours -
If I had time for one long work session, I could easily wrap up the F-706 bulkhead. Unfortunately, working an hour or two every other day is really dragging out this section. Today, I managed to get the F-730 plate and the F-729 rib riveted to the F-706 base. Once this was riveted, I final-drilled the F-706 sides to the base. Once drilled, I deburred the holes and prepped the sides for priming. With the primer sprayed tonight, I should be able to rivet the sides to the base tomorrow.
F-706, F-709 and F-710 Bulkhead Work (1/16/12)
Posted by Ethan Jacoby in Bulkheads, Construction, Fuselage on January 16, 2012
3.0 Hours -
Another day of bulkhead work…
My first task was to get some of the F-706 components ready for priming and riveting. However, before I could do that, I still had to match-drill, deburr, and dimple (as necessary), the F-706 base, F-730 plate, F-728 bellcrank channel, and F-729 bellcrank rib. Once that was done, I scuffed, cleaned and primed all of the angles and the F-706 base.
Next, I started working on the F-709 and F-710 bulkheads. The F-709 was the easiest to complete since it is a one-piece bulkhead and it only needed to be deburred and fluted for now. The F-710 was a little more complicated, but not by much. The F-710 is also a one-piece bulkhead, but it also requires a small length of angle to be fabricated.
I would have made quick work of the F-710B angle if I could have found the correct angle stock. However, I spent well over a half-hour searching the garage for the 17 inch length of .125 x 1 x 1 angle stock that was listed on the inventory sheet. Since it was checked off the inventory, I knew it was hiding somewhere. When I was just about to give up, I finally found it buried deep inside the parts crate. For some reason, I didn’t put this piece of angle stock in the same place as all the other angle stock! Once the angle was located, making the F-710B was a piece of cake.
F-706 Bulkhead Work (1/15/12)
Posted by Ethan Jacoby in Bulkheads, Construction, Fuselage on January 15, 2012
3.0 Hours -
I still feel like I’m doing a lot of work on these bulkheads with little to show for it! Oh well, back at it today.
The first thing I did was to rivet together the, now primed, halves of the F-707 and F-708 bulkheads. One bulkhead had 6 rivets that could be set now and the other had 8. All of these rivets could be squeezed, so they took no time to install. At least I now have a couple finished bulkheads to show for all my work!
I couldn’t delay the F-706 bulkhead any longer. This is the bulkhead with the really crappy looking parts. Specifically, the sides and bottom are a mess…very warped and ugly aluminum. After deburring the edges of the parts, I attacked them with my fluting pliers in an attempt to get them straight. This was a lot of work and they still aren’t as straight as I would like them to be. However the metal is so thin and flexible that I don’t think it will be a problem if I have to slightly ”pull” them into place with clecoes through the skin when the time comes.
Next, there are three angles pieces that have to be fabricated out of .063 x 3/4 x 3/4 stock. The F-728B and F-729B angles are easy as they just have to be cut to the proper length. However, the F-729C angle takes a bit more work. For this part, the stock is cut to length, and then the plans state to close the angle very slightly to 88.5 degrees. To do this, I just clamped the angle in my vise and continued to close the vise jaws until the angle was closed very slightly. Easy enough.

The plans say to make the angle 88.5 degrees instead of 90...not much of a bend, but it was easy to squeeze closed in my vise.
With all the angles made, I went ahead and match-drilled the two longer angles to the bellcrank support structure. The F-728B angle was drilled to the F-728A bellcrank channel, and the F-729B angle was drilled to the F-729A bellcrank rib.

The longer lengths of angle have to be match-drilled to the F-728A bellcrank channel and the F-729A bellcrank rib.
Finally, I clecoed the F-706 structure together for the first time. With the structure assembled, I could check the bend on my F-729C angle. It fit perfectly, so no more bending was needed. Next up, the structure will need to be final drilled, but that’s not going to happen today.
F-706, F-707, F-708 Bulkheads Continued (1/14/12)
Posted by Ethan Jacoby in Bulkheads, Construction, Fuselage on January 14, 2012
1.8 Hours -
I’m back to work on the plane after taking about a week off from the project. The main reason for the break is that I got married last weekend. We had a small beach ceremony in South Padre Island, TX. The weather was perfect and it was nice to see some family members that we had not seen in a while. Now, I’ve got to get this plane built so that we can cut down the travel time to South Padre. Six hour drives are no fun, but two-hour flights are!
Back in the garage, it took me a little time to remember what was left to be done on the bulkheads. I had received my #10 drill from Aircraft Spruce, so I decided to finish up the F-661EF flap bearing blocks first. After enlarging the first hole in the blocks to #10, I mounted the blocks on the F-705 bulkhead assembly with one bolt and a clamp.

After drilling one hole in the flap bearing block, I used a bolt and a clamp to position it for drilling the second hole.
Since I had marked a center line on the blocks, it was easy to make sure the blocks were straight. Once aligned, I used my air drill to start the hole for the second bolt. However, I only drilled this hole about 1/4″. Then, with the hole “marked”, I moved the block to the drill press to finish the hole since I didn’t think I could make a straight hole by hand through the two-inch thick blocks.

I only drilled the second hole about 1/4" while the block was clamped to the bulkhead...it will get finished on the drill press.
Once the second hole was drilled in the blocks, I temporarily installed the blocks on the bulkhead using the appropriate bolts, washers, and nuts. However, I only loosely installed the nuts for now since the blocks will be removed to rivet the skins.

The finished product. Only loosely installed for now since they will have to come off to rivet the skins.
With the flap blocks out-of-the-way, I moved on to the F-706, 707, and 708 bulkheads once again. As I stated in a previous post, these parts are just plain ugly and they need a lot of finishing work. For today, I finished deburring and fluting the F-707 and F-708 components. However, I decided to wait on the F-706 bulkhead parts as they will require the most work. Since these parts are all such a mess, I’m going to prime them. In this case, the primer is mainly for appearance, not corrosion protection. I managed to clean, scuff and prime the F-707 and 708 parts today, so at least I’ll be able to rivet those together and set them aside tomorrow.
F-706, F-707, and F-708 Bulkheads Started (1/5/12)
Posted by Ethan Jacoby in Bulkheads, Construction, Fuselage on January 5, 2012
3.0 Hours -
I couldn’t resist drilling the F-661EF flap actuator bearing blocks even though I don’t have the correct drill size yet. The closest drill I had to a #10 was a #12, so I chucked it into the drill press, clamped the block into place and drilled. The plastic was, of course, easy to drill, and I was actually surprised when I test fit a bolt and found that you really do have to go up in drill size when working with plastic. So, I’ll have to enlarge the hole once I get the #10 bit, but that’s easy. I’ll also wait until I have the other bit before drilling the second hole.

I started drilling the flap bearing blocks even though I don't have the right size bit. Clamped to the drill press with a piece of angle, the hole came out nice and straight.
Next, it was time to move on to some other bulkheads, so I had to spend some time rearranging the plans. I have so many large plans sheets now that rearranging them can take some time. It didn’t help that the drawings for the F-706, -707, and -708 bulkheads are split between two sheets.
After organizing the plans, I had figured out what parts I needed and set out on a search through the parts crate. After a bit of searching, I found everything I needed and got to work. The first thing I did was to locate and enlarge all the snap bushing holes for the rudder cables, wiring, and static system. Once these were all drilled, I started doing the finishing work on the bulkhead parts. These parts are in pretty rough shape out of the box. They are made from thin aluminum and they are severely warped in areas due to the way they are formed at the factory. Because of this, the bulkheads are going to take a lot of fluting to get them straight again. For today, I only finished the F-708 bulkhead components.



































