Posts Tagged ‘stiffener’

I Love Brackets

January 12, 2012

I must because I made the same one three times tonight. Probably lack of sleep this week has softened up the synapses. Basically I spent a frigid evening attaching a stiffener rib between 707 and 706 bulkheads. I got one J-channel trimmed down as well. I ran out of steam with the cold weather and covered her up for a few days of non-activity. See you next week!


More Forward Fuselage Work

June 21, 2011

Work travel, a renewed interest in running and enjoying the weekends with the family put the project in low gear for most of June. I have been working on a number of tasks in parallel. It’s definitely not the most efficient way to do things, but kinda of fun to change things up from one session to another. Tonight I finished the preliminary drilling for the Tank Attach Bracket. I spend the weekend making the F-796B angle 4 times (you only need two of them) because I kept screwing up the dimensions. The bolt holes look like they’ll be drilled later.

On the rudder pedal front, the brake pedals are ready to be riveted now. Then I can prep the rest of the rudder pedal assembly and drill the mounting holes in the F-719 forward skin stiffeners. Finally, on the floor stiffener front, the two center stiffeners, are all drilled except for the aft most holes on the cover support ribs. That leaves the two outer stiffeners to take care of once I get the floor skin back in place.

Started Floor Stiffeners

June 3, 2011

Not much time for the project tonight, but I did start to fit the floor stiffeners. The center stiffeners needed to be carefully fitted as there’s not much wiggle room with the rivets on either end of the angles. Also you have to notch the forward end to fit around a firewall angle. I didn’t have time to drill them tonight. I’ll have to wait to drill later in the week. Bummer.

Here is the forward end with the notch cut out to fit around the forewall angle.

This last hole on the aft end of the stiffener is going to be challenging to drill and rivet. Yeehaw.

Weekend Update

May 30, 2011

Nothing better than a three day weekend with good weather! In addition to lots of outside time with the fam, I got to dig into the forward fuse some more. Friday night I went through a the forward fuse progress and made a laundry list of to-dos including a drilling sequence for some of the critical drilling on the firewall angles. I did not want to screw those parts up and the instructions in the manual at this point are, shall we say, not explicit. They tell you “what” to do but leave the “how” up to the builder.

First I tackled the connection of the 719 stiffeners to the firewall. I had fabricated the 719B bracket a while ago but waited to drill the holes here until I looked at how others had done it. I ended up using Mike Bullocks method of a 12″ drill bit to drill the two holes in the stiffener and then a angle drill for the hole in the firewall flange. After some careful double checking of measurements, everything came out perfect.

Here’s a shot at the two holes I used a 12″ bit from above (below) get to. Some folks have removed the stiffener and drilled on the bench but I was worried about keeping everything aligned.

Next up was to finish the gussets at the intersection of the lower/auxilery longerons, the firewall mounting bracket and the vertical firewall flange. This must be the most complex intersection yet on the aircraft as three axes converge at the bottom of each side of the firewall. With the gussets I had two rows of rivet holes remaining to drill. I also has already cut the part out according to the plans. Saturday I spent the afternoon with my micrometer and files tweaking the edges until each gusset fit snuggly in place I felt good about all the edge distances.

Here’s a detail of the other gusset. The notch in the gusset is what allows it to fit inside the steel engine mount bracket but ouside the vertical firewall flange. However you can’t let the notch get too big in order to keep your edge distances tolerable. Confused yet? Me too. I took my time and drilled the vertical flange with the skin peeled back. Then used the skin to match drill through the bracket at the horizontal row above. It all turned out good and I’m very happy to move on.

On Sunday I prepped and installed the 902 bulkhead and the 7101 Gear Attach Web. There was a small gap where these parts meet up (see the four copper clecos in the pic above). I added a .020 shim between the parts for a better fit. The foward fuse with the bottom skin cleco’d back on is pretty stiff now. I am going to skip ahead and fit the floor stiffeners next before tackling the fuel tank attach and the rudder pedal install.


Firewall Countersinking

April 1, 2008

I finished all the countersinking tonight on all the stiffeners and gussets. The hard wood jig I use to hold the part while using the microstop in the cordless drill is working great. I started to dimple the firewall, but after a few holes trying to holding the part and dimple by myself I thought better of it. I’ll get Annabelle to help out later this week.

Tasks Completed:

  • Finished countersinking stiffeners and gussets
  • Started to dimple firewall

E: Priming Prep.

October 27, 2007
  • Washed, Acetoned, and Alumiprepped L and R stiffeners

E: Stiffeners, Cover Plate

September 24, 2007

–Finished dimpling the elevator stiffeners
–Dimpled E615 and the nut plates 

E: Stiffeners

September 23, 2007

–Scotchbrite stiffeners
–Started dimpling stiffeners 

Note: Dimpled one of the E720H stiffeners on the wrong side. Ordered replacement from Van’s. 

E: Stiffeners

September 11, 2007

–Trimmed the E 720 J, K and L stiffeners
–Clecoed left stiffeners 

E: Stiffeners and Prep

September 4, 2007

–Trimmed the vinyl on right elevator skin
–Clecoed stiffeners on right elevator skin 

Note: The tapered end on some stiffeners needs to be trimmed further.