Inspection cover in tail

[Luke68]

I made and inspection cover and backing ring for one side of the tail but now I'm not sure on how to attach it to the fabric once I get that far. I thought it would work just like a regular inspection ring but the nutplates are going to be in the way of it laying flat.
Wondering how others did theirs
thanks
Luke

[jaredyates]

Maybe you can cement the ring to the inside of the fabric, then make slits and wrap around the bits that used to be where the hole now is. Add a doubler with a 1" overlap on the outside fabric.

[Steve W]

Google Stewart Systems Paints or fabric covering videos. There are a bunch on YouTube. Watch them all and you will see what you need to know.

[Bdflies]

I used "Piper inspection Frames" from ACS:

https://www.aircraftspruce.com/catalog/cspages/inspectframes3.php?clickkey=3031725

Glue them on, where you want them, after the covering is shrunk. Cover with a doubler. Cut out the center after paint. I attached the inspection panels with clip nuts and sheet metal screws. Easy Peasy!

Bill

[Luke68]

When you say clip nuts I'm assuming you are talking about tinnerman nuts? That sounds like a great idea but do the nuts space the cover away from the fabric?

[Bdflies]

Yes, the proper description would be tinnerman nuts. No, the thickness of the clip is not an issue. When I made the covers, I 'eased over' the edges of the panels, meaning I bent the edges a bit. This allows the edges to contact the surface while the screws contact the tinnermans. Works great.

Bill

[Flygirl1]

Luke, Dennis and I used aluminum rivnuts or nutserts, I believe they are the same thing. There is a tool you use that squeezes them. There is a post or two about it. Type in "rivnuts" in the search. Some folks don't like them because they could spin in the hole. There are the keyed and unkeyed kind and we used the keyed kind. They are not something I would use in areas that I would be getting into a lot like the cowling. So far ours have worked well and are flat enough for our use. We also used them in the aileron and flap hinge covers. As far as attaching we placed our frame where we wanted it, like Bill said after the fabric has been shrunk. Then we cut a piece of fabric with the pinking shears and glued it over the frame, and then cut out the center. The holes were already drilled and matching the cover to the frame, then we used a wood burning tool to burn out the holes. Ours are round and custom sized. In a prior discussion about this somebody posted a link to a rivtless nut plate, which I wish I had seen before I had finished!! http://www.cherryaerospace.com/product/rnp

[Battson]

I found that after dozens of times installing and removing the inspection cover screws, the glue joints start to give in, and the fabric started to separate from the inspection ring metal in places. I am not sure how bad it will get in time, but repairing it isn't easy.

I am glad I attached my inspection rings to the steel structure, because it relieves stress from the glue joints and will keep things in place even if the glue becomes weaker. I put flanges on the metal rings, so they are stiff and self-supporting when you lean on them with a screwdriver. Otherwise they would flex and pull the fabric glue joints apart even faster.

[jim.mclaughlin924]

I glue aluminum frames on the inside, then cut an x in the opening and fold and glue the fabric back on the inside. finish with patch on the outside and rivet the nutplates through the fabric with soft A rivets. I have not flown my Patrol, but have not had any problems with the other 3 planes I have covered.

[svyolo]

I was wondering if inspection covers are necessary for the trim horns in the horizontal stab. I was thinking of putting a composite (kevlar) frame around it, and another piece filling that frame inside that I cut the slot for the horn. If I ever needed to get to it I could just cut out the cloth inside the frame, and add a patch after I was done. 5 minute patch job with Oratex.

I used kevlar to back the fabric in several places where it wasn't possible to support the fabric any other way.

[Nev]

Not sure how necessary they are, but I put some in. Just made the covers from .025 aluminium.

[spinningwrench]

In the tail I welded on some small tabs and then attached a permanent custom size inspection ring. No movement possible and a decent size to access the important bolts. Nut plates on the backside.

CEDC1908-C935-4E9C-B3A0-9463B3F355AF.jpeg2A7C7C13-6B86-4344-8800-F6FA9E9EC6BC.jpeg

[interstate al]

I wish I would have had your foresight to do the same! Those look great!

[Mark Goldberg]

Inspection ports on the tail should be installed as you will need access. For inspection and even the final set up and tweeking of things. For annual inspections for sure. Mark

[JimParker256]

Also helpful for disassembly in case you ever need to move the plane by other means than flying it... (See BackCountryPilots.org or SuperCub.org for many illustrations of people who've "earned the hat" by wrecking their plane and having to have it trucked or airlifted out...)

[Gerhard Rieger]

I will rivet the inspection ring to the stringers and fold the ceconite 101 around it