25 - Fwd Mid Fuse Bulkheads (completed); 26 - Mid Fuse Lower Structure (bottoms skins; seat ribs; baggage ribs)

This week saw the completion of section 25 and the start of what seems to be a very long section 26.  The fuselage is coming along and it was nice to bolt and rivet the seat ribs, and thus form the skeleton of the structure where my rear end will eventually find its home.  I dimpled the large center bottom skin - it was tough to get all the rivets but with a little bending, the center holes were not as much of an issue as I had anticipated.  The following were accomplished this week:

- riveted cover ribs and final-torqued bolts on forward center section bulkhead; reamed .311 and .375 holes
- deburred and riveted doublers to outboard baggage ribs and baggage ribs
- dimpled, fluted, deburred and attached nutplates to seat ribs; attached bushing clips, routing angles and doublers to ribs; riveted crotch strap assemblies (incl. nutplates); fluted outboard seat ribs and baggage ribs to match curvature of center bottom fuselage skin
- bolted and riveted seat ribs to F-01414 bulkhead; separated, deburred and primed seat belt attach lugs; deburred baggage ribs, routing angles, and seat belt lug brackets
- riveted seat lugs and lug brackets to baggage ribs; riveted F-01405 bulkhead to inboard seat ribs and outboard seat ribs and bulkhead angle; assembled and riveted Idler bracket assembly to F-01405 bulkhead; clecoed and match-drilled forward bottom skins
- match-drilled forward bottom skins; cut-out rectangles for gear legs; deburred and countersunk large skin stiffeners; dimpled and deburred small stiffeners; primed all stiffeners
- deburred forward and center bottom skins; up-drilled a bunch of holes; dimpled K1000-06 rivets
- dimpled center bottom skin; back-riveted nutplates, stiffeners and doublers to center bottom skin; separated, deburred and dimpled seat angles; straightened gear brace bars; primed gear brace bars

Reamed inboard 0.311" and 0.375" holes in the spar flanges:

 The rest of the images are a bit out of order.  Here are the doublers and stiffeners for the center bottom skin, which received a coat of primer:

Crotch strap assemblies assembled:

Seat ribs, likely midway through dimpling:

Dimpling the center bottom skin:

Fluting the outboard ribs to match the curvature of the skin:

Crotch strap brackets, deburred:

Final-drilled #27 holes for nutplates; also, rectangular holes for gear legs were match-drilled, rough-cut with a die grinder, and then final-sized with a hand file (and a lot of patience):

Here's the other outside ribs being fluted to match skin curvature:

The seat ribs bolted and clecoed to bulkheads - already, this is exciting; I can envision sitting on the left and making airplane noises:

Seatbelt lugs riveted to baggage ribs:

Doublers attached to different baggage ribs:

Match-drilling forward bottom skins:

Assembled and riveted idler bracket:

Seatbelt lugs, trimmed, deburred, and primed:

Seat ribs, bolted and riveted to center spar:

Attaching a bulkhead (F-01405) to the aft portion of the seat ribs:

Seat ribs, midway through bolting and riveting:

Stiffeners and doublers back-riveted to center bottom skin:

Primed gear brace bars: