3D printed system brackets [3.0 hours]

Under the front seats, there are four “systems brackets”, F-1084A/B, which have slots for a fuel line, brake line, and electrical wiring. In my case, there are two fuel lines, so one issue is how to deal with the return line. Another issue is the fact that s/s braided teflon lines are different in diameter than the Aluminium tubing lines that the system brackets were designed for. There is apparently enough scope to squash them in with a sliced apart grommet.

None of this sat well with me, and it was a simple matter to design a replacement upper bracket section and 3D print it in Nylon. There are two right-hand and two left-hand brackets, which have snap-in rings for two fuel lines, one brake line, and electrical wiring. Each ring has a slot for anchoring a cable tie, or waxed string tie, if needed. Each part takes about two hours to print, and bolts straight onto the standard lower systems bracket F-1084A. If in the future I need to make a change, I can simply print up new brackets and bolt them in place.

The brackets weigh 7 grams each. This replaces the metal upper section (F-1084B) and three snap bushings, which weigh a total of 9 grams, so there is no weight penalty in this change.

  • f15a
    f15a
    System bracket design
  • f15b
    f15b
    System bracket design
  • f15f
    f15f
    Part being printed
  • f15g
    f15g
    Printing complete
  • f15c
    f15c
    Parts replaced weigh 9 grams
  • f15d
    f15d
    Nylon system bracket weighs 7 grams
  • f15e
    f15e
    Plenty of stretch in Nylon support rings
  • f15h
    f15h
    Four system brackets
  • f15i
    f15i
    Bolts to standard metal parts

Section 28/29/31 marathon [71.5 hours]

Although I’ve in general followed the Van’s plans, like the wings I’ve tended to do things less incrementally. In the case of the fuselage sections 28, 29 and 31, this has resulted in a large tear down, de-burring. countersinking and dimpling activity which has occupied the last few weeks. The list of jobs to do seemed endless at times, but I finally¬†got through it. Not a lot of pictures across this time, my bad. There was a very large pile of parts to be primed at the end of this exercise. I primed everything except the five skins (aft/forward fuse, upper forward fuse) in one marathon priming session. I then went ahead with riveting those parts I could in the fuselage structure, as well as riveting sub-assemblies together. This reduced the huge pile of parts to a manageable size.

Next job is to prime the five skins, and rivet these to the fuselage.

  • f14a
    f14a
    Countersinking F-1004K center section side plates
  • f14b
    f14b
    Installed hard-to-get-to nutplate ahead of time
  • f14c
    f14c
    Dolly cut down, mid fuselage section in place
  • f14d
    f14d
    Parts for priming
  • f14e
    f14e
    Forward fuselage assembly riveted to mid fuselage assembly
  • f14f
    f14f
    Large batch of parts for priming
  • f14g
    f14g
    Large batch of parts primed
  • f14h
    f14h
    Ready to rivet replacement front angles to F-1045 forward fuselage ribs
  • f14i
    f14i
    Replacement front flanges riveted to F-1045 ribs
  • f14j
    f14j
    F-1046, F-1013 longerons riveted in place
  • f14k
    f14k
    Forward fuselage channels, longerons riveted in place
  • f14l
    f14l
    F-1044 forward fuselage rib assembly riveted
  • f14m
    f14m
    F-1044 forward fuselage rib assembly riveted
  • f14n
    f14n
    Other misc fuse assemblies