Starting the Fuse Center Section

With the Tail Cone wrapped up as far as I can go for now, it is time to move to the center section.  Although on the tail cone there are two rivets I have no idea how to buck at this time.   I will do some research online and wait for Bekah to get back.  But for now I am calling the tail cone done..

The center section mainly consists of the side by side seats and the baggage compartment.  Luckily I have started working on the ribs for the last few weeks so the initial stages aren't as daunting as they might have been.  There is a lot of rib prep that needs to go on.   Deburring and modification of the seat ribs, and don't forget the baggage compartment ribs.

My current delima is whether I am going to rivet or put in platenuts for screws for the seat floors.   The instructions allow for channels through the center of the seats with removable floors, but a majority of the seat floors are riveted down.   I will probably go with the instructions because my aft electrical is going to be pretty simple, and I am pretty sure I can get all my wires through the channels that are available fairly easily.   Also, if I need to pull up the seat bottom, the rivets can be pretty easily drilled out for access down the road.

The center section starts by clecoing everything together after the rib preparation is complete.  Here I get to go back and use some of the bulkheads I created in earlier steps.  The directions are much less specific at this point, so I am relying quite a bit more on the plans as I go through this.

Tail Cone - Almost Done

I had hoped to finish the tail cone riveting last night and got about 90% there, but realized I just wasn't on my game and had a few bad rivets.   When that happens its time to stop and come back another day.  I am finding the tail cone is more difficult to rivet the traditional way than the wings were; for some reason I think due to the curves or expanse of metal or something..  Anyway, tonight I will try some different techniques to see if I can get my rivets to be a bit more perfect.   If I had to do it again I would probably look into back riveting this piece.

Sorry for the blurry pics taken with my i-phone, Bekah has run away with the other camera. 

Visit to Vans

On our way to cannon beach for a wedding, Bekah agreed to stopping in at Van's.  Couldn't justify being that close to Vans without making a quick visit.   I was able to pick up some parts I needed and a couple will call orders from others in my EAA chapter, but most importantly, Bekah got her first ride in an RV..   I told her this would help her "understand" and even bring out the RV Grin..   It did, she had the best flight and now is re-energized as to what is going on in our garage.   

Also throwing in a couple pics of Cannon Beach..  Just amazing..

Tail cone riveting and small progress towards center section

Tonight Bekah was out in the garage again hammering away.  We made lots of progress on the tail cone, basically finishing all the bottom rivets.  Started the lower J-Channel riveting and hopefully tomorrow will finish to the point where we can flip it upright and work standing up for a change..

Also, I worked on the two center seat ribs a bit and trimmed them where the electrical bushings go through F-705..   I also finished trimming the sections where they open up for the control column.  The picture here shows how that works, its pretty cool.  In fact I might do this for the next outer two ribs so that I can install and remove the control column all in one piece..

Tail cone riveting

I cornered Bekah tonight and got 50 minutes out of her to start riveting the tail cone.  We made great progress as you can see.  There are a couple that need to be drilled out, but it is looking good.  Tomorrow we will finish the bottom, then start on the sides of the tailcone.

Longerons, all but done - Center section work just started

Now that the tail cone is up and ready to rivet, I decided to take some time on the longerons and starting some of the pieces on the center section.   I like getting a few things done ahead of time, then when the actual time comes you have had a chance to think about things and also it makes some of the busy work seem to get done quicker..

So with the longerons..  Measured them, then cut to size, then on the big bend  I used the Longeron Dies bought off of the forum sites.  Mixed feelings about them.  They create a great bend that is very consistent between the two, but do scratch the longerons.  I think I can sand out much of the scratches, but I still wish they weren't scratched to begin with.  Not sure if I recommend them, but I am happy with the consistency of the bend. 

The longerons are funny, because they really give the whole shape of the fuselage and are bent very specific, but when you look at them, it looks like you just ran them over and mangled them, but trust me, they are bent very specifically.

After initial bends, I lined up the canopy side rails on the longerons and drilled them.  In general, I think I got them nailed, because I can actually connect the two together.  Talk about accurate bends, and accurate pre-punched holes.  It lined up great.  I also bent the downward angles, that look like an "A" in the picture above.  The longerons are stuck together top to top in that pic, so the bends outward are actually downward..  Anyway..  The only remaining items on the longerons are removing a piece of the back section so that it fits on the rear bulkhead, and removing some of the material at the aft end of the side rails.  That can wait..

Also, I started working on the seat ribs.  Deburring them and creating spacers that go between the center ribs and F-705..   Also, the center 4 ribs get opened up a bit for the control column, as well two of them get cut out sections so that the control column can be removed once the ribs are riveted in place.

Tailcone - I am just gonna claim victory

After much stress I did figure out the problem.  It was completely in the "keeper rivets" that hold 712 to the rear of the tail spring.   These should be drilled in assembly so that you can be sure 712 is plumb with 711.   Just using the bottom skin does not ensure this "plumbness" so when in full assembly with side fuse skins if the keeper rivets are in place it will skew the tail in weird directions..  

So to solve my problem, I had a tough decision.  Removing the tail spring is impossible without drilling out several tough rivets on the bottom skin, which in turn requires taking apart the entire structure one more time, and ends up impacting many other componets.   So to avoid doing this I took the simple approach to center the offset holes between 712 and the tail spring while in assembly and plumb, then open them up to 1/8th for larger rivets.   Now how to deal with shims and dimpling of 712 without taking out the tail spring?  Well my dimples are somewhat still there from the smaller rivets but now have lined up and plumb holes.  I countersunk the rear of 712 slightly to allow for the bigger rivet.  This is no problem because there are two ribs together and the countersink will only impact the first rib.   So Viola !    All lined up with the larger "flush" rivets that won't have any impact on future clearances.  :-)  Flipped it upside down, now we should now be good to go for riveting.