More F-705 Fabrication And Reworking The F-705G

I started my Saturday with drilling the F-705K and the F-705L to the F-705F channel.  These are basically the components that allow the seats to be reclined to two different positions for traveling in comfort at 200 mph.  Anyway, the F-705 F channel is the only component of the three that is pre-drilled.  The F705K and the F-705L basically come as strips of aluminum.

Not pictured, you have to take the F-705K and bend a 4 degree angle in it (come on Van's>>>  4 degrees ?!?!?!?). Who can bend to that precision out of their garage?  Regardless of the specification that Van's has, the idea of bending the F-705K is so that when the F-705K sits on top of the F-705L, one end of the F-705K will sit on top of the F-705F channel.  Don't worry if this doesn't make sense, I have pictures of it below.

First thing I needed to do is figure out how to locate the F-705K and L on top of the F-705F.  Van's instructions just state "DRILL THE F-705J ANGLE, THE F705K PLATE AND THE F-705L SEAT ADJUSTMENT SUPPORTS TO THE F-705F CHANNEL."

Okay, not much to work with.  I can usually figure out this what I need to do by looking at the prints and referencing builders web sites, but sometimes I would feel a lot more comfortable if I had a little more direction...

Here is how I got everything to line up:

  • I drew a centerline on the F-705L, marked the first hole in 1/4" from the edge of the strip and drilled one #40 hole in that location.
  • I clecoed the F-705L to the F-705F channel and lined up the center line in the row of pre-punched rivet holes.  I colored in the last hole with a sharpie marker and then removed the F-705L to ensure that I had the last hole 1/4" from the edge of the F-705L.
  • I drilled all the F-705L holes to #40 using the F-705F channel as my guide.
  • Removed the F-705 L to transfer a couple of holes to the F-705K.

I had to scratch my head a minute on where to locate the F-705L with respect to the F-705K. 

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Here is the first #40 hole I drilled between the F-705L and K.  For placement of the F-705L, I positioned it up on the F-705K right where the F-705K the 4 degree bend was made.  The pictures below show better what I mean.

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I basically drilled three holes between the F-705L and K.  One at each end and one in the center so that I could cleco those two parts to the F-705F channel and drill the remainder of the holes.

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Here is how the F-705K & L sit on the F-705F channel.

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Just another angle.

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This picture shows my left to right alignment of all the pieces and parts.  I couldn't be happier.  Both left and right seat adjustments lined up this good.

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While everything was clecoed together, I countersunk the F-705K for the flush rivets it will receive later.

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I won't get into just how many times I have fabricated these angles....  Anyway, lets just say it was more than twice!!!  Anyway, one of the last things I had to do with the F-705G angles is to mill / drill a slot in angle to account for the canopy latch.  I chucked up a 3/8" end mill and put the angle in a cross vice mounted to the drill press.  With a little Tap Magic cutting fluid and some patience, I got some great looking slots cut into the angles.  The drill press doesn't make a very good milling platform, but it still did a significantly better job cutting the slot than I could have gotten with drilling a series of holes and doing lots of filing....

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Here is shot of what my cross-vice setup looks like.  Until I get my bench mill, this did an acceptable job.

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I clecoed the angle back into the F-705F channel and then filed the slot with all the parts installed to more or less make the hole  look uniform with all the parts.

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Just another shot....

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Here is what they angles looked like from below.  I had to dress up an area on this angle on the bottom left corner there.  On these angles, I didn't cut the 1/8" taper like Van's calls out.  I clecoed the angle to the F-705F channel and then sharpie marked the angle to taper the angle so it more or less lined up with the taper on the F-705F channel.  It isn't perfect, but it looks pretty good.

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This  side, looks better, if only the picture was fuzzy.....

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If I wouldn't have had to spend  3 hours re-fabricating botched F-705G angles, I would have gotten a lot farther.  Ooh well, not expensive mistakes, just time consuming.  Now I think I am going to move back up to the center section and finish some odds and ends up there.

I am getting really close to being able to prime and assemble something here.