Disaster strikes on the left F-7105B sub panel - 1.5 hour

Next step to finish the riveting of the subpanels, was to install the six AN4704-4 rivets to the fuselage rib. Unfortunately the access in this area is horrible for both the pneumatic gun and for bucking bars. The angle of the fuselage side skin makes things poor for the gun, and the lip on the fuselage rib makes it difficult for the bucking bar. I ended up using the double offset rivet set and the results were disastrous. 

The first rivet was ok, but not great. The second was about the same. The third was terribly slumped. Not any good at all. I have to remove these! Standard rivets are just going to be awfully difficult to set correctly for me.

 

After inspection, the two top left holes are in good shape, the bottom left is not usable. The 3 on the right are perfect and untouched. Now, how to figure out an acceptable fix? There is no question that I will order a new F-7105B-L sub panel. After consulting with some knowledgeable friends, we decided that replacing the F-902-L fuselage bulkhead is not the most wise. The fix we settled on was to clean and salvage the fuse bulkhead. Install a new sub-panel and fabricate a 0.032" patch to fit behind. Essentially sandwich the fuse bulkhead between the patch and the new sub-panel. Of course I will abandon the idea of using solid rivets here due to the high risk of damaging the parts...again. I will have to use cherry max rivets here.  

I used the dremmel and I deburred the holes with scotch brite. I used a round file on the large oblong hole to take out any sharp edges, as well I polished it with 800 grit sandpaper on the dremmel. I do not want any cracks forming from this spot. 

Next, I cleaned and prepped the areas to spot prime.

Started riviting the F-7105B sub-panels to the Fwd Canopy Decks - 1.5 hours

 Excited to finally get these pieces together, I started with clecoing the F-7105B sub-panels to the fuselage assembly. The easiest rivets to attack straight away are the AN4704-4 rivets that attach the Sub-Panels to the Fwd Canopy Decks.  

Priming the forward canopy deck parts - 6 hours

 Big day in the garage today. To start I cleaned and spot primed the fwd canopy decks to cover the newly installed rivets

Next, I took some time to debur, file and clear all edges and nooks/crannies of the forward canopy deck parts. 

 I set up the garage for a priming run which takes a while to set up and the process itself is a lot of work. Soap wash and scrub with scotch-brite, rinse, acid etch, rinse, MEK wipe, prime!

Installing the right F-721 fwd canopy deck - 2 hours

 I managed to squeak out a small work session today. I riveted the right F-721 fwd canopy deck to the fuselage.

 As well, I needed to dimple the holes for the vent support brackets in the fuselage side skins. I used the pop rivet dimple dies for this. While they do the job, they don’t do the best job at making a crisp dimple. On the other hand…ever try to drill accurate holes when they are already dimpled?…haha can’t be done. I will live with these being so so dimples.

 

 Last small item, I riveted the 4 nutplates onto the fwd canopy decks.

More brake line fitting - 3 hours

 I went back to Mopac and purchased 2-14" lines for the park brake to pedals, and 2-36" lines for the pedal to pedal connection. 

 

Do there is no doubt that the 14" lines are the correct choice over the 16" lines. However I am a bit concerned with the length of the 36" lines. They look right, and run nicely to the other pedal with gentle sweeping bends, however when moving the pedals back and forth, I see that I am getting some rubbing of the lines on the brake pedal tubes. To help combat this, I designed and 3D printed brake line clips to help separate lines. After installing them, they certainly do much to keep lines from rubbing together, however I'm still having some issue with the right pedal. I just need a little more slack in the lines. I might need to go back to 38" lines. 

 

 

 

Started installation of flexible brake lines - 1.5 hours

 Before I get the front deck into place, I want to ensure that I have all of the brake lines on the rudder pedals sorted out. The local auto race shop Mopac, which is similar to Summit Racing in the US sells stainless braided PTFE brake lines.  

I ended up purchasing 2-16" lines for the park brake to pedals. And 2-38" Lines to run from pilot pedal to co-pilot pedal. On initial fit, both look a tad long.

Perhaps I should go to the next size down line 14" and 36" respectively.

 One item that I did, was to route the brake lines through the lightening hole in the brake pedal brace. I 3D printed a type of 2-piece interlocking grommet/line holder out of black PLA. It took a revision or 2 to get it right. Holds the lines nicely in place.

 

Installing the left F-721A fwd canopy deck - 3 hours

 Well, this part of the build has taken some time to finally get to. Riveting the F-721A forward canopy decks to the longerons. Some builders choose to get these installed early in the canopy deck fitup. I however left it to the bitter end. (I suppose I don't like things becoming permanent unless they need to be).

Riveting these on is fairly easy when working forwards then aft. The tricky part comes in as you get to the last (aft) two rivets. Accessibility becomes very tight and in order to buck these I had to use a very long, but very slim tungsten bucking bar.