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Center fuselage forward: center console, floor, pedals.

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After putting the torque tube work aside, I moved forward and took care of the floor, center console and pedals:


Not much to report here. One of the pedals had incorrectly sized holes, so I ordered a new one.

Also the plans are not clear on the part number for the firewall floor attachment bracket :




Turns out this part was in my inventory under a part number not listed on the plans: CF-BKT-029!

Also, the center console skins can go in with M3 hardware, which is what I have, even though the plans cal for M4. Apparently a change that was done at some point and never communicated.


Fitting torque tubes in center fuselage

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Spent some times trying to fit the torque tubes in the center fuselage.

2 issues:

- The flap torque tube seems to fit a little tightly. It turns out the grooves in the ribs that hold this tube are not exactly perfectly lined up. So once you put the tube in fully, it's tight and doesn't move truly freely. The factory assures me that's ok. It's the flaps, which are motor actuated, so that's OK i guess.

- The rear elevator torque tube doesn't fit right at all. Turns out that's because the ribs are not aligned vertically. Unfortunately I never noticed this until now because when I assembled all of these, everything seemed to go in very nicely. I had no reason to suspect anything was wrong. That being said I should probably pay closer attention!



The factory suggests finishing up all the skins, including the sides and so on, to ensure everything is lined up and solidly put together *before* trying to put the controls in, precisely to avoid any such issues. So hop…

Front floor and insulation progress

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I have finally moved forward and begun putting the front floor together, testing with both layers:


And then added the foam insulation through the floor of the center fuselage:




I was debating whether to bother with the foam, since it is listed as "sound insulation" on the parts list, and modern headsets do a pretty good job of that already. It turns out however that this product is primarily a fireproof barrier, so good safety-wise, and also acts as a decent thermal insulator. So, in it goes!


Finally some progress with the main spar carry-through

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After an inevitable slow down during the gorgeous summer months, I had to deal some health issues, which means that progress ground to a near stop for several months.

In the past couple of weeks I have finally managed to get back into it.

I had some troubles with the main spar which caused some frustrations. Although the holes I think were all in the right place, the main spar has a spring to it, which means that even when fully clecoed in, things weren't aligned quite right.

So when I checked the gap where the main spars will fit, nothing was right! AND the holes had been matched drilled and enlarged incorrectly, uh oh.


It turns out the best practice is to put a precise and correct spacer where the main spar would go, and to then secure the main spar accordingly. Of course, the manual does NOT mention any of this.

Then I needed to fix those holes. That wasn't too bad. After checking with the factory, I could oversize to 1/4 inch, which is the size of the hole where the shop h…

Center fuselage progress

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After long boring work prepping the metal, I finally started assembling everything yesterday! All went quite smoothly!

Main spar and center fuselage progress

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Test fitted some of the parts to be attached to the main spar:
As it turns out however, the tube guides should not be assembled yet. You will find that the vesconite bushing mentioned in the plans is already mounted to the control tube, and therefore cannot be installed at this stage. I will instead mount the tube guides around the bushing on the control tube, and the whole thing will get attached to the main spar later ... this is how others did it as well it appears. Look for a future blog entry where i will likely show this later!
I've also been prepping the numerous other parts for that section of the fuselage. I decided for the first time to remove a strip of protective film, instead of the hole thing all at once. You do this by using a soldering iron to melt a line in the film, allowing to cut it without damaging the underlying skin:

Very easy to do and works nicely!
Here is the gear mounting box with some connecting parts I am testing for fit and making sure I understand ho…

A note on multi-grip rivets and grip size.

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TAF supplies Gesipa multi-grip rivets. This means these rivets can be used on varying thicknesses of material, and therefore "grip" various total thicknesses, hence the name.

The rivets have two lines where the material folds over, a lower and and a top one. When the thickness line sup with these lines, rivets look one way, whereas if the material thickness is somewhere in between, they look another.

This image illustrates this well:

Note how the right and left most rivets look, with the widest part of the bulge flush with the material, versus the two middle ones, where the bulge is a little removed from the material, looking more like a mushroom.

I came across a situation where I had two rivets of the same diameter, but different lengths, and used what I later realized was probably not the length the factory had intended (the plans were silent on this).

I ended up with rivets looking like this:


Now  had never seen this before, because normally you use rivets where the fold …