Filling Fuel Tank Rib Tooling Holes - Question

jdog0411 · #1 04-07-2021, 07:26 PM

Hi everyone,

I'm working on my fuel tanks for my 14A and have what is probably a dumb question, but i searched and didn't come up with anything.

The fuel tank ribs have two tooling holes each, and the plans say to fill these with 3/16 rivets. All of the ribs have these holes, and the plans say to fill them all in. I'm assuming that only the inboard and outboard ribs need to have these holes filled, correct? I can't think of a reason why the inboard ribs would need to be filled since they are internal to the tank, but maybe there is a reason I'm not thinking of. Wanted to check before I install the ribs and then find out I have to plug these holes while they are in place. Thanks!

Girraf · #2 04-07-2021, 07:34 PM

On my RV-7, the outboard rib was the only tooling hole that needed some sort of cover or 3/16 rivet (builders choice). The inboard rib tooling hole ended up getting covered by doubler ring and access panel. I left all inboard ribs alone. Can't imagine why the 14 would need inboard rib tooling holes closed up.

jdog0411 · #3 04-07-2021, 07:37 PM

Thanks for the reply, that was my thought as well. The 14 actually doesn't have the access panel in the rib like other models, so the inboard rib has to have the holes plugged as well.

I'll go with just the inboard and outboard ribs and leave the inboard ribs as they are. Will save me a few minutes of time. Thanks!

PilotjohnS · #4 04-07-2021, 10:04 PM

I am not sure about the RV14, but on my RV9, I enlarged the tooling holes on the ribs inside the fuel tank to help with filling the tanks. Something to consider.

jdog0411 · #5 04-07-2021, 11:42 PM

Thanks John, I will take that into consideration. I am planning on installing the ribs in the first tank tomorrow, so I will need to decide quickly. I'm following your build by the way....very inspiring!

HAL Pilot · #6 04-11-2021, 02:08 PM

I think the confusion is that the instructions do NOT mention the 1004 ribs which are all the "other ribs" There's a lot of gotcha's like this where you need to identify all parts sometimes on different pages to get full understanding of a set of directions.

So you only seal the outboard ribs in this case.

Step 7: The T-1003C-L & -R Tank Inboard Ribs-Fwd, T-1003B-R & -L Tank Inboard Ribs-Aft, and T-1003-L
& -R Tank Outboard Ribs each have two .188 [4.8 mm] diameter holes. These holes are used to hold the
ribs in proper alignment with the tool during hydropress forming of the ribs.

I added this thread to the WIKI (see signature)

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nohoflyer · #7 12-13-2021, 04:00 PM

Btw i am at this point and could not find the 426 6.xx rivets to fill this hole. Did i miss it?

Carl Froehlich · #8 12-13-2021, 04:16 PM

Quote:

Originally Posted by PilotjohnS

I am not sure about the RV14, but on my RV9, I enlarged the tooling holes on the ribs inside the fuel tank to help with filling the tanks. Something to consider.

May not want to do this for tanks on an aerobatic RV.

Carl

RV6-KPTW · #9 12-14-2021, 06:54 AM

The 14 fills adequately and does not need additional / enlarged holes for fueling.

Girraf · #10 12-14-2021, 09:49 AM

Quote:

Originally Posted by nohoflyer

Btw i am at this point and could not find the 426 6.xx rivets to fill this hole. Did i miss it?

Van's didn't supply any rivet larger than 1/8" in my kit. Its up to you to procure the 3/16" rivet if that's how you want to close the hole. I made a small plate held on with four NAS1097 rivets. Seems counter intuitive to drill 4 new holes to cover 1 hole, but it worked.