Question about note on stiffeners in tank

[Lemmingman]

I am just starting the assembly of my first fuel tank. There is a note on drawing 16A that says:

Note: Stiffener angle may be reversed (with free leg of angle closest to leading edge) to aid, if desired, in final application of sealant.

So far in my experience there are notes and there are NOTES! and the reason for the note doesn't always become apparent until you get to the part where you go "Man, I wish I had done what that note said.". So whats the deal here? Is there a stiffener somewhere that needs to be rotated?

 

[instructor_bill]

free legs

if you orient the "free leg" of the stiffener towards aircraft front you will be able to see the rivet shop head easier for encapsulation and inspection.

if you orient them the other way, you will need a mirror and four hands... ask why I know... I dare you.

 

[jpharrell]

I Just Followed the Plans

I installed the stiffeners as shown on the drawings (with the free edges to the aft) and had no problems at all with sealing the rivets. Access is wide open with the skins open before the ribs are installed (see the photo in the link below). Fuel tanks were pressure tested with no leaks.

http://johnsrv7a.wordpress.com/2010/12/13/finished-installing-tank-skin-stiffeners-2-hrs/

John
RV-7A
Empennage done, Wings done, Building Fuselage

 

[bird]

stiffeners

I reversed mine on the -8 as the note implied. I am using a capacitive fuel level system, so on those particular locations, I left them as the dwg. That allowed better clearance from the plates.

bird

 

[Smilin' Jack]

I installed them according to the picture and have no problem with the fuel sender or vent line.
Smilin' Jack
just posted new pictures along the way. The tank deal is a mess but one down and the other almost done will finish by the weekend. I ended up building the flaps while I was waiting for my wife to help with the riveting on the bottom of the tank. my arms are not long enough to do the bottom rivet on the top of the tank closest to the leading edge.
5 ribs done will finish the other 2 tomorrow morning and put the vent line in.

Just click on the picture it will take you to web shots.

 

[Smilin' Jack]

One last thing,

your using a back set plate and backset rivet. on the stiffners.. it is not hard to see your work.
Jack
Were keeping pretty close with the building ...

 

[Lemmingman]

Thanks for the comments, everyone.

 

[instructor_bill]

if you encapsulate the rivet shop heads all at once...

if you encapsulate all of the rivet shop heads at once like I did, you would wait until the wing ribs are riveted too. You can't open it like a taco anymore. So if the loose leg is towards the back of the tank, you won't be able to see the shop heads.

I didn't have any leaks, but it'd have been easier to encapsulate all of the shop heads before adding the tank ribs, or spin them 180 degrees.