Wed Nov 26 2008

Fitting F-7101 web plates

These first three images are from last night. Here are the two shims I mentioned on the previous page. They're made from scrap .025 thick alclad.

I could see that the F-7101 web wasn't nesting well into either the auxiliary or lower longerons, so I marked the edges for some chamfering.

After a few passes with the file, it was clear this chamfering process wasn't going to be all that quick. So I decided to call it a night and get some sleep. I'll finish this up tomorrow.

After work, I got the F-7101L completely fitted. There's actually quite a bit involved in getting this thing in position, so I'll detail the process for the F-7101R on the right side.

First, remove the lower longeron and set the F-7101 in place on the auxiliary longeron. Only put a single cleco in here at this time near the bottom of the fuselage (top of image).

Then I used some AN470AD4-4 rivets to hold the auxiliary longeron in position.

Once I was sure that those rivets extended through the skin into the auxiliary longeron, I installed one more cleco in the upper / aft most hole.

Then it was just a matter drill, cleco, drill, cleco until...

...the F-7101 is fully drilled through the auxiliary longeron.

Next, I reinstalled the lower longeron. Notice the single AN426AD3-5 rivet here in the single hole I had previously match drilled through the skin into the lower longeron. I'm using a couple clamps to hold everything tight together.

Repeat the drill, cleco, drill, cleco process until the F-7101 is fully drilled through the lower longeron.

Now remove both the auxiliary and lower longerons and the F-7101 and debur everything.

Cleco the parts back together on the bench... you can check where the F-7101 needs to be chamfered (or radiused) to eliminate interferences like this.

Next, spend some time with a file until all the parts nest nicely together.

Then reassemble the whole shebang. Now that the F-7101 can be clecoed down tightly to the auxiliary and lower longerons, the forward flange of F-7101 can be used to transfer drill into the F-902 bulkhead.

Another disassembly, fit the shim and...

BAM! Got 'er done!

Well after that I was in a mood to do something (engage Monty Python voice here) completely different, so I broke out the brake pedals and started deburring. I clecoed all four plates together using my recently acquired long-reach clecos and sanded all the sides smooth on the disc sander. I suppose there's no real good reason to have all four parts exactly the same size like this, but it appeals to my sense of uniformity. :-)

A little more time with the file had the outside edges smoothed down.