Continued Forward Fuse initial prep

Tonight I experienced the good and the bad.  First off I was able to trim and drill the Aux Longerons.  All went well, and I was excited to see additional strength come into the firewall connection.  These required some trimming and a bit of a twist to make sure they fit correctly, no problem and look good.

Then I started working on the skin stiffeners.  The first one went well, with lots of trimming and even modification of the bend where it rides over the F704 flange.  I even put a slight bend in the stiffener so that it matched to the skin quite nicely.  Worked great on the first one as you can see taped to the skin for drilling..   On the second one I learned what angle can do if you try to bend it just barely too much.   All at once it twisted in my hands and then whamo !    You can see what happened... Needless to say I was mentally done for the night..  Now to order new parts from Van's..  The only good news is that this won't slow me down because there is much more to do on the forward fuse..   I can keep busy, just is frustrating..

Firewall Drilling and Misc Items

Tonight I was able to ensure the firewall was lined up correctly and drilled all the side skin holes through the Stainless flange on the firewall.   I am sure glad only the firewall is made of stainless because it is very tough to deal with.   All went well though as I drilled from the Top longeron to the bottom..   (Bottom up in the pic, since everything is upside down.  ;-) ).   Also, when complete I made sure it was clamped tight and was able to drill the longeron through the top firewall extension.  You can see this step in the pictures.  It turned out great.  

 Also I am adding some pictures from last weekend that I forgot to post.   I trimmed and drilled 2 of the 4 connecter straps.  But I am fresh out of .063 aluminum, since I used the other straps that were provied for other parts, so now I might have to borrow, or buy new from Vans to finish the job.  Also, I drilled the side ribs to the skins and opened up the pilot hole for the pitot/wire run..  Over the next few days/weeks I will need to match drill the entire fuse, so I thought I would get started.

Longeron Trimming and Firewall

I was able to move forward quite a bit over the weekend.  In this session, I trimmed the longerons at the firewall.  Van's has you  make them about 3/16 inch too long and them trim them back in this step.  It took a couple of tries and then some filing, but I think I got them perfect.  Below is a before and after pic.  After the second pic, I had to file it back a bit more to allow the firewall to be set back far enough.

Next on the firewall, per instructions I drew a center line on the bottom aluminum flange to use as a guide to set the distance of the firewall from F-704.  Then slid it in and measured 5/8 inch back from the blue skin all the way around.  Looks pretty good, so I drilled the two outside holes and put in clecos to hold it.  Next the instructions say to "take a brake" so I am going to put it away for tonight.   Next I come back and drill the firewall to the skin, which is a fairly important step..  So will come back, re-measure everything, then go for it..

Drilling the Longerons

Today I spent about 4 hours working through the longerons from tip to tail.  Basically you use the pre-drilled holes in the skin and with the longerons in place, drill what seemed like 1000+ holes all the way through the angle.

Forward of F704 I used additional clamps to make sure the longeron was aligned perfectly with the forward skin. Drilling these took forever, and really gave the compressor a work out. Glad this is behind me.

Conical Bend #2

I finished the second conical bend and didn't crack the skin, which is great news..  But for some reason I don't think this bend is quite as good as the first one, but it still looks pretty good.  Actually, I can tell you the two bends are different, but I can't tell you which one is better, its kind of wierd..

Anyway Here are some pictures of the process that I used and the finished product.   Note, I put some tape on the backrivet plate, which protected the metal in the focus area of the bend.

Conical Bend #1

Last night I had a bit of success with the first conical bend.  These bends are fairly challenging and builders commonly end up with cracks at the focus point of the bend.  Even after you do it on the first skin, many people end up cracking the other skin, so until you are done there is always risk here.   Luckily my first one went successfully.  The first thing I did was deburr where the bend was going to take place.  I completely worked this with emery cloth until it was a very fluid edge..  Then I went for the bend.

I borrowed some predrilled angle from a fellow builder and was able to cleco this to the tab on the side skin.  Using my backrivet plate clamped over the skin to the table and a vice grip, I slowly bent the skin in a single motion.  Then worked the tip with my thumb until it was approx 90 degrees.  Hopefully I can get more pics on the next one.  When I pulled it off the table, it looked pretty good and just took a bit of finesse and Bekah's help to get it in place.  Turned out pretty nice..

Side Skins and Arm rests

I was able to get the side skins onto the structure.   It wasn't easy, since when you first match them together, the cleco holes were off by about 1/2 inch where the rear of the skin matched to F-706, so there was a lot of movement that needed to happen to get them to line up.  The entire fuse needed to flex around a bit in order to get them lined up.   Once they lined up though and I got a few clecoes in,  the structure became very rigid, it was pretty cool to see..

Also, looking at my longerons, the forward bend was pretty spot-on with regards to the side skin.  I don't think I will need any tweaking as you can see here, they both fall exactly along the line of the skin.

Also, before I work the conical bends in the side skins, I put the arm rests in and predrilled the holes.  Its funny Van's has you do this now because you immediately pull them out and then they sit on the shelf for months..  Also, I didn't drill the hole yet where the armrest connects to F-704.  Not sure when this is supposed to happen, as F-704 isn't predrilled, I didn't want to put a hole in it yet until all the parts are together.   Drilling a non pre-drilled hole might be so slightly off at a later date if there is something else that uses the hole..  So better safe than sorry for now.

Center Section/Aft Fuselage Joined

This weekend started with the notching and trimming off the aft end of the longerons.   I don't have any pictures of this process, but I did it by the book.  Measured it out, drilled the holes, used a hacksaw to do a rough cut, then filed them the rest of the way smooth.  I think I know why Van's has you be so careful measuring the longerons in the beginning but then has you cut them a bit once they are mounted.   Lots of builders have indicated that the length isn't that critical in the beginning because of the step where you cut it at the end.  Well, I think the length is critical because when you are bending and drilling the side rails, you measure from the FRONT..  Then when you notch for the F-11 bars you measure from the REAR.  If you don't measure the length to begin with correctly, then you risk having it not match up in the middle...  Anyway, mine are looking good so far and but I haven't got all the way to the end yet, where they get cut shorter.  You wait until the the side skins are mounted before you know for sure.

After the Longeron work I had some local friends stop by to check on progress and I talked them into helping me flip over the center section so I could mate it to the aft fuse.  Big step and a bit stressful, but overall it went really well.  This hunk of metal is getting big now for sure..  Thanks for the help guys !

One thing I did here that might help other builders, not sure, but it definitely didn't hurt.  When I riveted the bottom skin on the center section, I left the aft 2 rivet holes open on the baggage ribs.  This made it a bit more simple to fit the bottom skin over the F-706 bulkead..  for what it is worth..

Also, I haven't mounted the side skins yet, so I don't know fully that my forward longeron bends will match up perfectly or not, but it is looking good when I compare it to the bend on the F704 side plates per the pic below.

Here is just a gratuitous shot from down below looking up the fuse..

Side Ribs and Seat Belts

During the latter part of the week, I was able to finish up the side seat ribs on the center section.  They were fairly straight forward.  Lots of fluting to get the curve just right, but also, I think mine seem to have been bent just a bit different than others.  The rear part is absolutely flush with F-705..  The instructions say to let the outside of the rib stick out just a bit from the seat skins by about .032.  This worked well, but at the very aft part of the seat pan (next to F705), there was no way I could get that much out of it.  But in fact the seat pans stick out past the edge of F705 anyway..  Which really tells me I need to get the seat pans on the scotchbrite wheel a bit longer and take off some of that aft edge.   I am fairly sure things will work out OK here, but looking at other sites, it appears that the side ribs on some other builders just stuck out a bit more from F705..  Which really doesn't make sense to me anyway, since the skin has to be smooth across the two of them.   Does it make sense to you either?   I didn't think so..  ;-)

Also, I know it is way too early, but I ordered my "Crow" 5 point harnesses and they just came in.  Was going to go with Hooker Harnesses, but the cost of these was just way too attractive.  Turns out the harnesses themselves look awesome and I am really happy with them.  Rebekah and Libby approve as well and says they look very secure, which is important in her book.  Now to just figure out the bushings that I will need to get and how to mount the crotsh strap in the plates that I worked on a few weeks ago.

Center Section Bottom Skin complete

Bekah jumped in and helped for another 45 minutes or so and we were able to finish riveting the bottom skin on the center section.  It went well and we were able to turn it over and see the results..  Looking good so far, now need to work the side ribs and then I get to join the center and aft sections together.  Either this thing is starting to get bigger or my garage is getting smaller.  ;-).

Brake Pedals ? ?

I know, it is a bit out of order for the typical build, but I had extra time and Rebekah wasn't able to help riveting until later in the day.  So I took a couple hours and got through the majority of the fabrication on the brake pedals.  They aren't too tough, but they do get confusing until you get an understanding of which pedal you are working on and what is the front and what is the back.   I also took advantage of cutting out all the "lightening" options that Van's recommends.  Takes a bit more time and saves about .000001 of an ounce..  But looks good and worked for me.  Now they will sit for a while, but when I need them they will be ready.  I might end up anodizing them down the road for a clean looking tough finish, but we'll see.

Also,  After Bekah got home this afternoon, she helped me get started for about an hour riveting the center section..  We got about 1/2 way through it in one hour as this piece of riveting really goes fast.   I bucked from the bottom and she shot straight down from the top.    Worked my arms and her back quite a bit, but we got through it.  Can't wait to get finished and turn it upside right to see what we have..

Center Section - Bottom Skin

I have had some challenges on the seat/baggage ribs but have overcome them fairly well and am ready to move on.  The first problem was a rivet that didn't agree with anything I wanted to do to it.  It was in the forward section of the seat ribs where they connected to the F-704 bulkhead.   It was really messed up and I was worried that I would have to drill it out and use a bolt in its place.  I carefully drilled it out and luckily was able to put a replacement in that was a bit more cooporative.   Looked good and I moved on.  Ran directly into another problem with the baggage ribs.   I accidentally riveted two in reverse order..  Don't ask me how I did it, but boy was it frustrating..  Drilled those out and re-ordered them, then with everything back in shape I put the bottom skin on ready to final rivet.   This should go quickly, hopefully through the weekend I will be able to get this done with Bekah.  Mistakes are funny becausee you feel like its the end of the world until you rectify them.  Then depending on how you fixed them, it still bothers you until you do it again, or replace a part etc..   Luckily, in all my mistakes I am 100% confident with the fix before I move on..  No sleepless nights here.   Ya Right..   ;-)

Center Section Rib Riveting

So the riveting has gone well, all except for one rivet.   I will need to drill it out, and hopefully replace with another one, or even widen the hole and replace with a bolt.   I hope not to do that due to the added weight, but won't know until the rivet is out and I can inspect the hole.   All other rivets are pefect though and this one will come around with a little TLC.  Next step is F705 onto this assembly, then baggage ribs, and bottom skin.   Not long now and I will be joining to the aft fuse.

Center Section - The riveting begins

Now that I got through some of the "extras"  ( i.e. the electric aileron trim and crotch plates) complete, I am able to start the riveting of the center section.  Hopefully getting back to a consistent pace throughout this week.

Also, you can see how I gave myself more edge distance on the crotch strap plate.  Not that it is even really needed in this case but I wanted to be sure, so now the crotchstrap is bomb proof.