CHAPTER 32 - Bulkhead Fabrication
The firewall came nearly pre-punched. I guess I had not noticed that the design had changed, but gone was the double-'x' pattern of stiffeners, replaced with single cross-stiffeners on each side. Made sense to me. I ordered the recess because, even though I intend on fixed pitch, I wanted the flexibility to change my mind later or have extra room in case an accessory demanded it. Anyway, it was a simple matter to drill out the pre-punched holes and add the additional shims and such. You can't see it on the first photo, but I also tentatively marked the locations for firewall penetrations. That photo was taken before I got myself a halogen worklight; the second one is after. I like my worklight - bright-as-day visibility and garage heat all in one go.
Well, I still had not located a painter (the local EAA chapter was checking out some leads for me), so I got started on the next bulkheads. The local Home Depot sliced up a sheet of 3/4" particle board for me (that rig they have is slick) and I used double thickness to simulate the wing spar. You can see in the third photo that I used the splice plates to bolt it all together and used the spacer material Van's provided to space the forward bulkhead parts at either end. In the next shot, you can see the oversize hole I made in the 'spar' for the trimtab cable and (almost under the clam) the oversize hole where the control mount would go (three other locations as well). I don't think I need access to the other spar holes, but I can always drill out the mock spar if I do. The spar was bolted into the bulkhead with ordinary bolts, saving the good bolts for actual assembly.
Ok, on to the F605 bulkhead. I laid out the geometry on a sheet of particleboard, then assembled all the components. Nothing to it. Tapering the rear spar mounts (not shown) was farmed out. My landlord teaches a sheet metal class and the students (or at least one of them) eagerly ran the parts through a bandsaw for me. I have been doing so much filing and hacksawing that I finally broke down and purchased a pair of mechanics gloves; raking a vixen file across my knuckles was the last straw. I should have done this a long time ago. The second photo of the F605 shows the left side muddle where all those little pieces come together for the seatback. I was surprised that the rivet pattern did not continue all the way up the F605E but I stuck to the plans and also omitted the holes for the canopy latch. It seems a little sparse there; if someone has heard something I haven't, please let me know.
Finally, I fabricated the F611, again getting bar stock tapered for me. I cut out the center section using a hand nibbler after drilling the corner radiuses. Pretty simple, overall. By the way, you can see the nifty cleco holder I made from a detergent bottle. I bought a larger size so I can do the same with all my #30 clecos. *grin*
The rest of the bulkheads will be finished in the jig, so it's time to start riveting - except still no painter. Oh, well, I just head down to the local airport, walk into the FBO and ask. Wiseman Aviation, being the nice folk they are, accept my little job; you can meet my new painter by going back to Chapter 28. While I wait for parts to be painted (they can only do a few at a time), I'll find other things to do...