2004-10-10


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I've deburred and dimpled the other R-901 skin, Here it is hanging back up. The instructions at this point say to prime the stiffeners and back rivet them to the skin. I'm going to hold off on that until I have a few more parts to prime. Like maybe the entire rudder skeleton. So... on to the skeletal assembly.
You have to enlarge the hole in R-904 to match the 3/8 hole in R-902. 
This is accomplished most handily with this baby.
Now, fabricate the R-917 shim. Start by cutting it out.
It needs to fit right underneath R-904. It make a nice flush surface with the flange. 
The drawing says to use the spar as a drill guide. So I'm going to clamp the shim to the spar...
...and mark the holes to be drilled with the sharpie. Those of you who have been paying attention will notice that I've found one of my black sharpies. 
Except now I can't find my center punch. I want to drill two holes on the drill press. 
Then I'll match drill the center one.
Round the corners and it's finished.
I have no 3/8 inch bolt to attach the rudder horn in place while I drill it. So I used a bunch of clecos to hold it in place, moving the cleco out of the next hole to be drilled and placing it in the newly drilled hole as I go along.
Now you cleco the rudder horn (R-405PD) to R-904. Check to make sure that the flange sits flush against the horn. (it won't, see red arrow) You have to radius the edge of the rudder horn so that it does. I used a file to file a radius in R-405PD.
Now it fits perfectly. You can see the radius that I filed clearly in this picture. (yellow arrow). It is interesting to note at this point that the instructions say to drill 4 holes in the aft edge of R-405PD as per the detail view on DWG 7. Except there is no detail view on DWG 7. There is a revision note that says the detail view was removed. Ahh well, I guess it's ok since the holes are already in R-405PD anyway.
Now cleco R-606PP, R-607PP and R-608PP reinforcement plates to the spar. And, just like it says, One goes on the fore side and the other two go on the aft side. 
Time to flute some ribs. BTW, if you ever want to get the labels off of the part, this stuff takes the glue off with very little effort. Flute the ribs so that the holes in the flange are in a straight line. You can check it with a straight edge. 
Cleco the R-913 counterbalance skin to the ribs. This was easier said than done. 
Now cleco the skins to the whole mess. This thing is looking like a rudder. 
Now, on the the rudder brace (R-710). It says to trim the excess material from R-710. Hmmm, must be talking about this wackin' big piece of aluminum. Just follow the dots. 
Fits in there nice and snug.
Now make the R-918 rudder bottom attachment strips. The only way I could match drill these babies was to drill the first hole "freehand" and then cleco the strip into place. Then I used these clamps placed so that there was one clamp supporting the strip right where I was applying pressure with the drill. Made both of the strips and now it's time to take it all apart and deburr, dimple and smooth!

That'll have to wait until tomorrow.