Rollbar mounted!
I managed to get some time in on the project this weekend after a visit to my mom's and working on the 'honey-do' list.

With the rollbar riveted, it was time to get it mounted on the fuselage. I clamped the 631C/D angles to the frame and drilled holes for the keeper rivets. Pull them off and riveted them together. Next step is to mount them to the fuselage. The plans really don't help you out a lot in this area. I found one measurement on DWG 40 that calls for a 19/32" inch center line. I marked that point just as a reference. In the end, I cleco'd on the F-774 skin and used it as a point of reference. The angles set just about up against the aft end of the canopy deck. I did have to trim the passenger side a little to get it slide far enough forward. Once I was happy with the position, I clamped and drilled.

Pilot side 631C/D drilled.

With those mounted I started the test fitting of the frame. I marked where the frame ends need to be trimmed to wrap around the angle. A couple of times off/on and I had it pretty good.

Where frame end wraps around angle.

I pulled off the 631C/D angles and filed off the outboard edge to match the contour of the fuselage sides. This was by far the hardest part of the whole process. I just couldn't figure out a good way file the material off. I managed to get it done using about every power tool and file I had.

I modified the 632A channel to help hold the frame. (Tip: The channel is 19 5/16 long, so it needs 5/16" trimmed off the end AND THEN the 5/16" angle cut made.)

Frame in position with channel.

I also made the 732B angle. TIP: The plans call for the 3 holes that mount the angle to the 706 bulkhead to be 1/2" (exact center). Don't do this! As Paul discovered, these leaves the angle positioned to high and it rests against the flange of the 706 bulkhead, which would not provide clearance for the rivets that attach the skin to the bulkhead. I drilled mine about 3/16" higher than called for to allow some clearance.

As your can see.. the holes in the 706 bulkhead are exactly 1/2" from the flange.

Here it is positioned lower to allow clearance for the rivets that go above.

Oh yea... TIP #3 for today. As you can see in the picture, one of the 3 holes in the 706 bulkhead that is used to attach the 732B angle is part of the vertical bellcrank channel. In an earlier tip I mentioned to leave this angle off so you could back drill some of the holes.. where here is another place you can't get too if you drill that angle on too soon. I had to measure over and just kinda guess where the hole was.

View from rear.

With the frame in place, I drilled and tapped the holes in the angle for the screws that mount the frame. (Only the two forward screw holes get tapped.)

Finished and skins attached.

View from front.

Now that things were securely in place, I match drilled the little 732E and 732C's in place.

F-732C angle

F-732E angle

That completed the mounting of the rollbar. Things need to come off for a little deburring and then it can get painted.

The electric facet fuel pump came a week or so ago and I had bolted it in place. I wanted to run the fuel line from the selector up to the pump. Paul seemed to have a lot of trouble with the bends in the line at the pump end, so I focused on that end first. I managed to get the bends right after some work but then screwed up the fuel selector end. I need to pick up some more tubing for try #2.

Felt good to make some progress and get the roll bar complete!

(Time: 6 hrs)


- posted by Matthew @ 7:22 AM