Wing root rubber channel.

Has anyone successfully used a rubber channel, other then the one Vans supplies in the wing root gap cover?

I been having a bear of a time getting the fairing in place and screwed down with the rubber channel in place. I gradually trimmed back to a 1/4" gap and now the rubber seal doesn't have quite enough pressure to maintain a nice curved shape against the fuselage ( and it was still very difficult to install it).

Spruce sells a channel that is a little wider ( http://www.aircraftspruce.com/catalog/appages/opencenter.php ) that I thought might work.

Any ideas or suggestions?

3/16" is the max you can go for a nice fit and still have pressure to the fuselage.

Try this

This may sound over simplified but make sure you have the smooth side up. Make the sure the gap is right and then tape in place as you install. Once it has been installed for a few days it will form and be easier to remove/replace.

Rick_A said:

......I'm having a bear of a time getting the fairing in place and screwed down with the rubber channel in place.....

Click to expand...

Rick,

The channel that Van's uses is quite acceptable. I cut the gap as narrow as practical so that mine tend to fit tightly all around. The downside to that is installing the seal in the first place. One slip up and you have to start all over. I never could get it installed by starting on the upper wing surface first. On the -8, I eventually learned to loosely insert the rubber gap seal on both the upper and lower fairing pieces held together with a cleco button then start the installation process with the aft-most screw on the lower surface and then working my way up, over and around.

This is a tedious/difficult task

You are not trying to seal tanks here so study carefully what you are dealing with in the current state. My first reaction is, if you can't get a good looking installation with the rubber touching the fuselage all along the edge I would back off and start over with new closure strips and proceed very persistently (and that has it's own new set of challenges) before going to nonstandard seals. That is only my arm's length view. Thinking about it a little more as you have certainly done I think in a situation like this rubber is cheap and certainly is an option to consider - I would probably buy it and try it if I couldn't get the original materials to work. I had a difficult time getting them on with a good fit also. I did finally get them on with a tight fit against the fuselage. It is a a intuitive belief that the rubber has to be jammed hard against the fuselage to do its job but I'm not so sure that is true. Under certain conditions even with a pressure fit the sealing rubber will blow out of the interface and beat against the fuselage and wing until the rubber is bonded to the closure strip with yellow 3M Weather Strip Adhesive. When I pulled up after the diving pass of the finish line in the 2005 AirVenture Cup race at well over 200 mph the rear of one blew out and the beating noise of the loose rubber was alarming even above the engine noise with my David Clark Headset. It left black marks on the wing and fuselage but they were cleaned off and no damage resulted for the incident. Now years later they go back on after the annual condition inspection fairly easily and with adhesive they stay in place during extreme conditions even though I have modified the plane to get it 12 kts faster than it was back then.

Bob Axsom

Use a few spots of 3M trim cement to glue the rubber on the AL fairing prior to installation.

Wing root rubber channel

Warm the rubber as much as practical to make it more pliable. Also, use an awl or very small Phillips screwdriver to align the screw holes as you go, installing only every third one or so. On first install, an extra pair of hands helps.

As Bob stated, it's a tough install when the rubber is new. Over time, it will conform more to the fuselage, and in fact will begin to get loose. I have 451 hours on mine and I will probably replace mine this year for a tighter fit. The more Gs you pull, flexing the wing, the more the rubber gets worked around. As happened to Bob, I've had mine come loose in flight and it will get your attention.

I guess I'm going to have to bite the bullet and re-do the metal gap cover. The seals are no so bad that will need to re-do them before my first flight but I think over time they will be too loose.

Live and learn.

Rick
I have an extra set of covers if you need them

Jeff, check your PM's. Thanks.

How far back on bottom side?

My seal went on real well except at the aft bottom location. The trim aluminum overlaps the fuselage bottom surface there and the thickness of the channel part of the seal keeps the aluminum trim from laying flat. What have others done here? Did you take the rubber all the way back and let the aluminum push down or did you cut the rudder off short and let the aluminum lay flat against the bottom of the fuselage?

I put a tab on the end

I riveted a thin aluminum tab onto the rear end of the wing root closure strip on the bottom side of the wing. The tabs are located on the inside of the wing and I slip them inplace behind the wing skin when I install the strip. Locate where the tab can do the end securing job, mark it clamp on the tab, drill several tab mounting holes through the closure strip and tab clecoeing each hole as you go, take apart, shape the tab for surface (round off the corners and debur the edges, debur the holes, dimple, rivet. I used this tad approach in several places for skin butt joint alignment (aluminum and fiberglass) etc. In the RV-6A the MLG fairing also has a securing effect for the aft end of the closure strip on the bottom of the wing .

Bob Axsom

Jeff Vaughan, great guy

Jeff, I received the wing root gap covers today. Thank you very much - I'll definitely buy you more then 1 beer when we run into each other.

Rick

Rick,
Glad to help. They were just gathering dust.
Looking forwrd to the beer!!

Tape the seal to the gap covers then put a little baby powder (used on your inner tubes) on the rubber seal and it will go on real easy.

Refrigerator gasket

I'm not to the point of fitting these wing root seals yet, but it sounds like a tip I learned when fitting a refrigerator gasket may come in handy:

Throw it in they dryer for a while before fitting it. It warms the rubber up nicely and becomes much softer and easier to work with.