[sbalmos]

I'm scratching my head a bit. I know the center rib of the instrument panel is the most important one. But I'm trying to figure out how I will match-drill the flange that mates to the firewall (it has no holes), and then how to match-drill it to the firewall itself (which has no holes for the center rib). I'm thinking clamp together the center and one of the side ribs' flanges, and just match-back-drill from the side rib flange into the center rib's? Then, with the skin on so the rib is centered, play Gumby and twist myself underneath, and try to match drill the rib to the firewall? Sounds painful even for my relatively-young self.

Further, as I came to determine, the instructions say to drill the stiffener angle to the rib first, then later cleco the rib and panel subassembly to the firewall. But when I did this, I ended up with what looks like a 1/16" gap between the stiffener angle's bent tab and the firewall upper stiffener it's supposed to mate to. I'll almost certainly just cut a new angle, and match drill it while the rib is cleco'd to the firewall so I can ensure this tab is flush to the firewall stiffener. Or should I just shim it?

Anyone else experience this?

 

[cajunwings]

Center rib angle

Just did this last night and saw same issue. What I did: Cut the notch and bend the angle according to the plans. Clamp the bent up tab to the firewall angle. Mark the angle thru the rollbar brace bolt holes with a sharpie to check for correct edge distance. Needed to raise the rear end of angle 1/8" to get holes centered in angle which required enlarging the slot in the sub panel just a little. I'm replacing the firewall, all the forward ribs & sub panel and everything came pre punched.

Don Broussard

RV 9. Rebuild in Progress

 

[rapid_ascent]

I think the problem is the instructions don't explicitly say to attach the angle to the firewall angle. I think it should be clamped before you drill the angle to the center rib.

 

[sbalmos]

Ray, there's a rivet callout to attach the two.

All, I talked with Sterling tonight (actually, the first time I've ever actually called into the factory builder support line ). He had no problem with just shimming the gap. As for drilling the rib's flange to the firewall itself, we discussed a couple options, like I mentioned in this thread. I'm just going to cleco the top skin back on, so the rib is in the proper centering position, and just lay out a few rivets at their proper locations on the firewall itself, then match-drill both the firewall and the rib flange at the same time. One way or another, talking with Sterling, you just have to eyeball and lay out the rivets on your own, since the tip-up version apparently doesn't have this rib.

 

[rapid_ascent]

I guess I was thinking just make another angle piece. Clamp it to the firewall angle then drill it to the center rib, then you won't have a gap. Maybe I'm not understanding the issue incorrectly.

I've been working on my panel and these pieces seem to have lots of degrees of freedom. I keep buying more pieces so I can finalize my panel support frame, but I still seem to not be able to exactly position the ribs onto the frame. I may have to give up on this until I get further along I guess. I made the center rib angle, plate and then decided I couldn't put them together yet. The top skin piece might resolve my problem but that seems like too much for where I am now.