FIREWALL AND BULKHEADS PAGE 3

 

 

The F-705 bulkhead was not quite complete yet.  The assemblies that hold the upper seat backs in place were not installed yet.  The photo at left below shows the 2 F-705J angles, the 2 F-705K plates and the 2 F-705L shims cleco’d in place.  The photo at right shows these assemblies riveted in place.

 

Seat back retainers cleco’d in place Seat back retainers cleco’d in place

 

There should be pictures of the installation of the seat belt ribs here but I have misplaced them.  One of the problems associated with my lack of time (and maybe desire) to add to this photo log on a daily basis is the threat of loosing photos or loosing the disc that the photos may be on.  Whatever the case, the pictures of the seatbelt brackets are forever gone.  I will say that one must pay very special attention to the drawings when drilling and assembling these parts.  The drawing is slightly confusing and I misdrilled two of the brackets.  I was able to salvage the parts by changing their position from inboard to outboard but I regret that I do not have photos to document the installation and also the mistakes.

 

Bulkheads F-706, F-707, F-708 and F-709 were assembled along with the center fuselage or the aft fuselage.  The next bulkhead that I will describe in this section is the F-711A, B, C, and D and the F-712A and B.  The photo at left below shows one of the F-711C horizontal stabilizer attach bars being drilled on the mini-mill to match the holes in the F-711B (aft half of bulkhead).  These two attach bars are made from AB4-187 X 1 ¼ bar stock per drawing number 21.  The photo at lower right shows this F-711C cleco’d in place.

 

Drilling one F-711C One F-711C in place with clecos.

 

To drill the other F-711C I clamped it to the first one , drilled one hole, installed a cleco in that hole and drilled another hole at the other end.  I put a rivet in that hole to keep the holes precisely aligned and then I proceeded to drill the rest of the holes.  Why so much bother you ask?  Actually it was easier drilling the second F-711C from the first rather than the bulkhead.  Also this made the two F-711C bars inter-changeable.   The RH photo shows the next hole during the drilling process.

 

F-711C horizontal stabilizer attach bars F-711C bars during drilling process

 

The photo at lower left shows the horizontal stabilizer attach bars freshly etched, alodined and primed hanging with the F-711D angle and the F-710B angle to dry.  When priming just a few parts, I use a “Pre-Val” paint gun.  This set up combines all of the advantages of a aerosol spray can with 2 part epoxy primer.  This process is quicker than using a pressurized paint sprayer when priming just a few parts.  Clean up is quicker and easier too.

 

   

 

 The picture at lower left shows the aft half of F-711 (F-711B) with the horizontal stabilizer attach bars cleco’d on.  Next to each bar is a small slot.  In the far right of the photo is a larger slot, vertical in the photo.  The material between these slots gets cut out on both halves of the bulkhead along the lines I drew in pink (arrows).  The photo at right shows this modification (The picture was taken after the F-711 A and B were riveted together).  The F-711D is also attached at this point.  The center part is the F-710 bulkhead with the F-710B angle attached.  There is not much to this part just the web and the angle.  The last part on the right is the completed F-712, parts A and B riveted together.

 

711B prior to modification 710, F-711 and F-712 assemblies

 

Did I forget to take pictures of some important steps?  Why yes, of course I did. Sometimes I get so wrapped up in the assembly process that I simply forget to take pictures of important steps.  Other times I take pictures of the wrong part of an assembly sequence.  And last but not least is the Flash Card that I obviously lost that contained pictures of the seat belt brackets plus who knows what else.  Documenting this airplane assembly is as educational as the assembly process itself.  At any rate, the "Firewall and Bulkhead" portion of this project are completed.  The rear fuselage is next.