 | 2005.11.25:
(2.5)
Started working on the seat backs. Cut the lightening holes in
the F-638 seat back braces. Cut lengths of angle stock for four
(4) F-637B and four (4) F-637C. Measured/marked trimming details
on the F-637B and F-637C angles, and F-638 seat back braces. |
| 2005.11.26:
(4.0) Trimmed and deburred
the F-638 seat back braces. Started shaping the F-637B angles. |
| 2005.11.28:
(2.0) Finished shaping the
F-637B angles. |
| 2005.11.29:
(5.0) Rounded the vertex of
the two top F-637C angles to nest in bend radius of the F-637A seat
back skins. Deburred all the F-637C angles and F-637A seat
back skins. Measured out drill patterns on the F-637B and F-637C
angles. |
| 2005.11.30:
(2.0) Pilot-drilled the
various support angles. After drilling the first bottom F-637C
(without the rounded vertex) I realized that I had misread the plans
and measured/drilled the pilot holes in the wrong locations. I
suppose I could have still used the same part by re-measuring and
drilling on the other leg of the angle, but I decided to just make a
new one. |
| 2005.12.01:
(2.0) Cut the various
hinges. Match-drilled the bottom hinges to the F-637C
angles. Started fitting and drilling the seat components. |
| 2005.12.02:
(2.0) Fitting/drilling... |
| 2005.12.03:
(2.0) Finished
fitting/drilling the seats. |
| 2005.12.30:
(2.0) Started riveting the
seat backs using the squeezer. |
| 2005.12.31:
(2.0) Finished riveting the
seat backs except for 10 rivets each that I couldn't reach with the
squeezer. |
| 2005.01.01:
(1.0) Finished riveting the
seat backs using the rivet gun and C-frame. First time using
this technique, and it's a piece of cake. As easy and foolproof
as back-riveting, even without a helper and driving AD4 (1/8")
rivets.
 |
| 2005.01.16:
(2.0) As other builders
have noted, I found there to be an interference between the cabin
frame mounting brackets and the seat back supports. I trimmed
the seat back supports slightly to clear the interference, and then
riveted them to the bulkhead.
While this interference was not a big deal, I was curious to find out
why it was so. Putting in the seat backs, as well as carefully
studying the plans, revealed an apparent design error. The seat
back supports are positioned on the bulkhead 1/4" outboard of
where they ought to be. The plans (and pre-punched holes in the
bulkhead) position the seat back supports 20" apart
center-to-center, whereas the seat backs are positioned 19.5"
apart center-to-center. I sent an email to Van's tech support to
inform them of this, but they didn't seem too interested in
understanding the issue. I'll move on. |
