Oh **** moment need advice

[nacoblio]

So I got a lot of work in today on my tank. I should have stopped 20 min before I did. I think I was tired and made an error in reading the plans and orienting my inboard tank rib. The image below is of my T-703. As you can see I did not have the part oriented correctly when I drilled the first hole for the fuel vent line. I realized my problem and drill the correct hole. So now I have to decide what to do with the bad hole. The way I see it I have three options.

1: order new parts and build the a new rib. (my least favorite and I don't think necessary)

2: Use the bad hole for a fuel return line. I was going to install one anyway but I was planning on putting it up higher on the rib and having it return fuel to the third bay. Anyone see an issue with putting it lower on the rib and working the fuel return line to the top of the tank in the first bay then straight over into the third bay?

3: creating a patch. Cutting a piece of AL to fit over the hole and using tank sealant to close the hole. If I did this would it be necessary to sandwich the rib between two pieces of AL or could I just put a patch on the outside?

Any advice is appreciated

Also while I am at it. I have read about people using HEX head screws to secure the fuel tank access panel. Are those ordered from vans? Anyone have a part number or link if they are from an outside source.

Thanks

[ed. Pic link added: https://photos.app.goo.gl/zgSJU6MofuHHqSkc9v/r,dr]

[az_gila]

The hex head would be these...

https://www.aircraftspruce.com/pages...ws/nas1801.php

They are full strength structural screws. They are also useful for other spots where it is hard to get a Philips screwdriver in.
Yes I know about these, but the above screws also allow a wrench to be used...

https://www.sears.com/craftsman-7-pc...p-00947477000P

An alternative may be Allen head screws.

[jcarne]

I can't see the picture to give advice on the rib.

I did however use these screws for mine. They worked great! I'm glad I used them too as I had to remove one of the end plates to gain access to the inside.

https://www.aircraftspruce.com/catal...es/NAS1351.php

[PilotjohnS]

I seem to have made the same mistake and drilled the tubing hole in the wrong spot. I just patches with a plate on the inside and two tank pull rivets. Held pressure fine and should not be a problem.

I used stainless allen screws ( internal hex) from the aviation isle of home depot. I did rhis because i want to be able to remove the plate while the wing is still on the airplane. Also, watch the torque on these screws, it is easy to over torque, which would make it a bear to remove in a cramped space.

I used stainless because my experience is around fuel tanks, screws tend to rust easier.

[Draker]

I can't see the picture, but if it's anything like the mistake I made:



I decided to patch it and build on:



It looks like this on the outside after sealing it with the black death, and did not leak:



As for the tank access plate screws, I went with hex head cap screws as well. Ordered them from Aircraft Spruce. 24 total. I used part # NAS1352-08-8P. This is only how I did my own tanks. Make sure whatever you go with is suitable to your needs.

[nacoblio]

Thanks for the help. For some reason the photo I posted is not showing up for some people so here is a link.

https://photos.google.com/photo/AF1Q...vbM7aZmy9a6aZY

This tank is not going to have a flop tube so does anyone see a reason I cant use the hole for my fuel return line? I have looked ahead at the plans and I cannot see a issue but I would be interested to see if there is anyone a little further along who might have some insight.
Thanks again to everyone.

[tomkk]

Originally Posted by nacoblio

Thanks for the help. For some reason the photo I posted is not showing up for some people so here is a link.

https://photos.google.com/photo/AF1Q...vbM7aZmy9a6aZY

This tank is not going to have a flop tube so does anyone see a reason I cant use the hole for my fuel return line? I have looked ahead at the plans and I cannot see a issue but I would be interested to see if there is anyone a little further along who might have some insight.
Thanks again to everyone.

Getting an error with the link: "The requested URL was not found on this server. That?s all we know."

[lr172]

Originally Posted by nacoblio

So I got a lot of work in today on my tank. I should have stopped 20 min before I did. I think I was tired and made an error in reading the plans and orienting my inboard tank rib. The image below is of my T-703. As you can see I did not have the part oriented correctly when I drilled the first hole for the fuel vent line. I realized my problem and drill the correct hole. So now I have to decide what to do with the bad hole. The way I see it I have three options.

1: order new parts and build the a new rib. (my least favorite and I don't think necessary)

2: Use the bad hole for a fuel return line. I was going to install one anyway but I was planning on putting it up higher on the rib and having it return fuel to the third bay. Anyone see an issue with putting it lower on the rib and working the fuel return line to the top of the tank in the first bay then straight over into the third bay?

3: creating a patch. Cutting a piece of AL to fit over the hole and using tank sealant to close the hole. If I did this would it be necessary to sandwich the rib between two pieces of AL or could I just put a patch on the outside?

Any advice is appreciated

Also while I am at it. I have read about people using HEX head screws to secure the fuel tank access panel. Are those ordered from vans? Anyone have a part number or link if they are from an outside source.

Thanks

#2

There is no need to bring return fuel outboard or even to the top. Just put a bulkhead AN fitting in the hole and your done. Fuel comes into the tank under pressure, so no need to have the line above fuel level.

Larry

[nacoblio]

Still trying to figure the photo thing out. Thanks to everyone for their input.

Another shot. I am trying to use google photo.

https://photos.app.goo.gl/zgSJU6MofuHHqSkc9

[Paul Thomas]

A patch or return should be fine in that area.