Is a doubler needed for outboard fuel sender?

[DonMcKee]

I am going to install dual CiES fuel senders in my RV-14A tanks. The outboard senders will be installed in the most outboard tank bay on the aft baffle (0.032 Alclad), using nutrings, either Textron/Cessna style (picture), or the beefier ones CiES sells (picture in this post).

With nutrings being used, do I need additional doublers, too? If yes, can you point me to any "how-to"/best practice documentation for using/making doublers? I looked in AC-43.13-1B, but I didn't find anything appropriate.

 

[Ralph Inkster]

How heavy are these senders? Any heavier than stock senders from Vans?
Those mounting rings look tough enough to hold a tank together!
Will you be able to position those senders far enough away from the tank filler opening so some uncaring rampie doesn’t snag it with a filler nozzle?

 

[bertschb]

I didn't install a doubler but then I'm not an engineer. I used the Cessna style nut rings FWIW.

 

[Phil Sprang]

No doubler needed. I’m not an engineer either but the guy that designed my ER tanks is and his plans allow for the outboard sender without a doubler.

If you are interested in the Cessna nut rings, I have some, brand new, that I’d be willing to sell. Send a DM if interested.

 

[HAL Pilot]

Here's my write up on the WIKI. I did a doubler but only because I am not an engineer. Probably didn't need it.

 

[DonMcKee]

No doubler needed. I’m not an engineer either but the guy that designed my ER tanks is and his plans allow for the outboard sender without a doubler.

It looks like you're building an RV-14A, too. Is the baffle on the ER tanks the same 0.032" 2024-T3 Alclad used on the standard tank? Do the ER tank plans call for using nutrings outboard, or do they call for nutplates? Are there any concerns re: Normal vs. Utility vs. Aerobatic category structural requirements?

(I'm assuming that nutrings will provide more "doubler-like" support than nutplates will. Correct?)

 

[Phil Sprang]

It looks like you're building an RV-14A, too. Is the baffle on the ER tanks the same 0.032" 2024-T3 Alclad used on the standard tank? Do the ER tank plans call for using nutrings outboard, or do they call for nutplates? Are there any concerns re: Normal vs. Utility vs. Aerobatic category structural requirements?

(I'm assuming that nutrings will provide more "doubler-like" support than nutplates will. Correct?)

I'm building a straight -14. As far as I know the aft baffle on the ER tanks are the same as the standard tanks, but longer. My standard tanks were quick build and I sold them so I can't measure the aft baffle and my ER tanks are installed, so I can't measure them either. Sorry. I did not use nut rings as the ER tanks called for nut plates, just like Vans. The only difference that I can tell in the ER tanks are that the plans call out an option to add outboard senders.