Rib stiffener layout question

[LukeS]

I'm getting ready to mark and drill the ribs for stiffeners, and looking at drawing six the stiffeners all appear to be placed perpendicular to the chord line, which is difficult to draw on the flanged rib. What methods have those of you that have completed this step used to located the stiffeners? I honestly wonder if they could just be eyeballed, but I don't know how critical their placement is. I could always build a jig, but don't want to over think it if it's not that crucial.

[dedgemon]

One each Mark I eyeball

[John Rheney]

One suggestion: look at where the stiffener leg (perpendicular to the rib web) is in relation to the rivet locations for riveting the skins to the ribs. You can flip the leg to be either left or right to avoid blocking your bucking bar later on.

[LukeS]

One suggestion: look at where the stiffener leg (perpendicular to the rib web) is in relation to the rivet locations for riveting the skins to the ribs. You can flip the leg to be either left or right to avoid blocking your bucking bar later on.

Good tip. It would definitely be better to flip the leg than just wishing it wasn't in the way.

[bestbearhawk1231]

I just eyeballed them making sure it wouldn't interfere with where the skin rivets will be. In other words, I tried to get the upward leg as close to the flutes as possible.

[LukeS]

Thanks guys, I was hoping it was that simple.

[DRLPatrol]

Don't forget that the rear stiffener on 2 of the 0.032" mid ribs in each wing are also the attach bracket for the false spar. They are 0.32" and location is critical. Don't ask how I know.
Doug

[LukeS]

Don't forget that the rear stiffener on 2 of the 0.032" mid ribs in each wing are also the attach bracket for the false spar. They are 0.32" and location is critical. Don't ask how I know.
Doug

Thanks for the reminder! I had thought I would save those for assembly, to make sure everything lines up OK. Can you think of any reason I shouldn't do that?

[DRLPatrol]

That should work.Or lay a false rib up against the mid rib and that will show you where the false spar will land.
Doug

OOPS; Just noticed that this was in the 4 place section. I am building the patrol but I guess it still applies.