The seat belt anchors do not have pre-punched holes, so they have to be lined up with the holes in the F-705 bulkhead.  Each anchor is made up of two F-634 brackets.  To attach the anchors, I first drilled a hole in the left brackets as shown in the plans.  I then made a spacer out of wood in the shape of the bracket to position the right brackets.

With one side bolted to the bulkhead, and the spacer in place, I put a bolt through the opening where the seat belt would normally attach to keep the two brackets aligned.

I used clamped the right bracket to the F-705 bar with a block of wood to give it some support, turned the whole thing over, and match-drilled the hole.

Then I simply repeated the process for the four anchors, and put all the little brackets away for a while!

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Trimming F-705C Rear Spar Fork   July 25th, 2010

The two F-705C form a ‘fork’ that the rear spar bolts into.  The inboard end of the F-705C gets trimmed to save some weight.  I drew out the patter to trim out, making sure there were at least 0.25″ from the center of the hole to the edge.

I used the bandsaw to remove most of the material, and then used a hand file to round out the end.  Unfortunately, I can’t find any pictures of the finished part!!

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Fabricating F-705B Doubler   July 24th, 2010

This doubler bar is where the wing rear spar is bolted to the fuselage, as well as the seat belt anchors.  The picture below shows how a single bolt through this bar attaches the wing rear spar to the fuselage.  The distance from the bolt to the edges is critical.   The drawings call for the bar  to be 45-3/32″ long.

I started out by measuring 45-8/32″ to get 5/32″ of ‘headroom’ before cutting.

This is my el-cheapo abrasive cutter — makes these kinds of cuts very easy.

After the bar was cut to the right length, I used the drill press and the lower piece of the bulkhead to drill all of the holes.

Here is the F-605C, which goes on top of the F-705B bar.  This one is a little long as well, so it had to be cut down to length.

Finally, here are all of the bottom F-705 pieces , including the little spacer bar.

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F-705 Real Bulkhead Spacer   July 14th, 2010

This little bar goes between the ‘fork’ that accepts each wing’s rear spar.  We start out with a piece of aluminum bar, and cut out two pieces:

I am still surprised how well my Sears bandsaw cuts through aluminum.  I just use a little cutting oil and it goes through like butter (well, not quite, but still very effortlessly).

One of the corners needs to be filed about 1/32″, so I just clamped in a vice and filed a little at a time until it matched the dimensions on the drawings.

Here is the end result.  Nice and shiny…

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