Friday November 27, 2009
Rolled F-770 Side Skins, Drilled Longerons, Started Fitting Firewall
(1.0 Hours Aft Fuselage, 2.5 Hours Center Fuselage, 3.0 Hours Forward Fuselage)
6.5 Hours Total

The fuselage is getting really large. We moved it about as far back toward the garage door as we could and that leaves about a foot between the front and the workbench I have up there. Will have to rearrange to give a little more space.

First up today, we drilled the F-720 armrests to the side skins (after some fluting to get them to fit). Then, the side skins had to come off in order to roll this little piece that curves over onto the bottom. We experimented for a little while with the bending process until finding a method that worked out pretty well.

Here is the right skin rolled and cleco'd back in place.

And here's the left skin post-bend. I think they both came out very well.

The next task was to drill the side skins to the longerons. This mainly involved a lot of careful clamping and drilling. Here's the left side, drilled up to the F-704 bulkhead. Note the closely spaced line of clecos along the bottom.

And the same for the right side (remember, it's upside down).

Then, I checked for longeron length on the forward side (the manual specifies 3/4" between the front edge of the side skin and the longerons. As others have mentioned, it's silly that they have you cut the longerons to such precise lengths back in a previous step. Anyhow, both of my longerons were about 1/8" too long, so I used my die grinder with a cutoff wheel to make the trims.

Then, more clamping and drilling of the longerons to their forward edges.

Easy...

I made and drilled these F-704L straps that connect part of the F-704 bulkhead to the longerons.

Finally, I clamped the firewall into place and cleco'd on the forward bottom skin. It's wrong in this next picture--the sides of the bottom skin fit underneath the side skins. I fixed it after taking this picture.

It looks like my left longeron is still a little bit long and is preventing the firewall from sitting back where it should be (by about 1/16"). So I need to take the firewall off and trim the longeron again. Then, I'll be able to start drilling the firewall to the side skins.

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