Saturday April 23rd, 2005|
Still Cranking on Center Section Bulkhead
Last Thursday I left off cutting the control assembly mount brackets. This morning I got up and cranked up the band saw and finished cutting them.
Here you can see how rough the band saw cuts can be. No biggie though, that's what Scotch-Brite wheels are for.
Here are the brackets after I finished polishing them.
Next I drilled out the holes for nutplates on the top flanges of the center section and riveted on the nutplates that go there. Note the cut-outs here for the stick movement.
Here's the other top flange of the center section w/ nutplates installed.
Here are the 'cover support ribs' clecoed to the center section web. These things get nutplates on them and they get riveted and screwed to the web. I drilled these out then unibited the holes for various runs (not shown).
Here's one of the end cover support ribs. This thing actually get screwed on to the web. I'm not really sure why...but that's what the plans show. See below.
Heres's the plans. A web stiffener goes on the other side and gets a couple of nutplates riveted to it. The cover support rib attaches with screws into those nutplates.
Here's the stiffener material after I cut it down to size. These get match-drilled against the pre-punched holes in the bulkhead.
Here are the stiffeners after the match-drilling.
This is my first opportunity to use a nutplate jig. I bought these a while back but haven't had a reason to use them, since most of the nutplate anchor holes are already drilled on this kit.
...and here's another entry for my 'Blood Sweat and Tears' section. I did this while drilling out the small cover support ribs. Nothing like a #19 bit to the palm to get your day going.
The support ribs sit on top of some flush-head rivets...so I counersunk the holes in the spar web for those.
Next I started to fabricate the center section spacers...but.....the spacers where pre-fabbed. I found 'em in a bag. Nice to find stuff like this already done.
The bulkhead gets these 5/8 inch holes/snap bushings for electrical & manual elevator trim runs. I'm using electric elevator trim so this will get electrical wiring instead.
...and on the other side as well.
Then I started riveting the vertical pieces to the horizontals. I was able to squeeze all but the inboard-most row of rivets. I used this method to rivet those. If your'e not familiar with this, this is the way all the 'old school' rv builders had to rivet their spars. The spars weren't pre-assembled and they would use this method on all the thick materials. I can't imagine how long that took.
Anyway, several good whacks with the rubber mallet and the rivets were set quite easily. Gives you some perspective on how much force you're pneumatic squeezer or rivet gun are excerting on rivets.
How about an action shot? Jaime took this picture of me banging (literally) some rivets. Please ignore the filthy garage.
This method drives absolutely perfect rivets. Check these out!
Well, it was a fairly productive day today. I'm hoping that tomorrow I'll be able finish up the center section and move on to the next bulkhead.