---------------------------------------------------------- Europa-List Digest Archive --- Total Messages Posted Sun 12/28/14: 2 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 08:37 AM - Re: Warping or shrinkage of fuselage around and below fuel fille (Bud Yerly) 2. 01:01 PM - Re: Warping or shrinkage of fuselage around and below fuel fille (willydewey) ________________________________ Message 1 _____________________________________ Time: 08:37:49 AM PST US From: "Bud Yerly" Subject: Re: Europa-List: Warping or shrinkage of fuselage around and below fuel fille Willy Short answer: The dent is caused by fiberglassing the plastic neck to the skin directly. As the fuel vents vapor, the neck cools and shrinks, deforming the outer skin. Techniques to allow the skin and neck to move independently are time consuming and must be made to keep the neck secure in all directions yet movable... To prevent damage during refueling one has to consider making the neck firmly attached to the fuselage, in the event a line boy sticks the filler in the fuel neck and hang on it. Failure here would be a disaster. It is necessary to secure the neck hard to a reinforced fuselage side. Techniques: We prefer to heavily reinforce the fuel neck skin attach area as a safety precaution. On a new build, simply put a 1/4 inch piece of blue foam just larger than the cobra neck width by at least 1/2 inch. Bevel the edges at a 45. It should be from 1/2 to one inch shorter than the curved flat cobra section. On a used aircraft, cut the straps off carefully (you will find that epoxy sticks to the PTFE plastic very well). We often cut the FS18 neck completely off. Then heat the metal ring and remove. Consider installing the new style cap at this time. The outside dent will be a problem. All I can say is de-paint, fill, glass over, fill again, and repaint. We at Custom Flight Creations simply fit our neck and filler and mark the skin. Remove and add the foam and put two layers of glass over it. Use micro and flox as appropriate. Many have asked how we curve the foam to the skin. In the past we used large clamps that reach in, however, you can also score the foam, use micro to stick the foam and simply use long sticks to hold it in place. To be honest we now use blue foam safe super glue to tack the foam at the top and bottom and hold it secure until the micro cures. Obviously, one must leave the foam free of micro in the superglue tack areas. Once it is stuck we then smear micro and flox over the foam and put two layers of glass over the foam and peel ply down the sides and across the bottom. Done in a day. Reinstall the cobra neck and cap in place over the reinforced skin (Redux the cap area). Apply glass straps as per the manual over the plastic and lap only to the foam reinforcement area. No problems encountered in 16 aircraft. On another note. To prevent line boys from messing up our aircraft, we supply our current owners with 1 inch clear PVC flexible tube to fit over the fuel filler tube, and long enough to go down into the neck to fill. That way the shutoff on the nozzle (if it works) will kick the fuel off before a fuel explosion on an over fill. I have the line guys keep it on low flow and watch the fuel in the hose. When the hose fills with fuel, stop. Once the fuel burps down, you can fill some more until it fills again. Now, it is typically full. Unfortunately, seeing exactly how much fuel you have is difficult. You just can't dip the tank in a Europa XS or Classic. So often, guys fill to the neck. I use a sight gauge, (see my website) but if over fueled it is not uncommon to fill the top of the sight gauge also. Then you have to clear the fuel out of the top vent portion of the sight gauge. So a vent clearing technique has to be used by attaching a 1/4 inch tube to a nipple inside the fuel neck. Yea, that's convenient on a hot day. But better than not knowing how much fuel you have at all or depending solely on an electrical gauge. It is very difficult to keep an overfull fuel tank from venting and often once you have filled your tank, the fuel expands and drips out over the top staining the paint) or if your vent is underneath, then on the ramp. If your vent for your sight gauge is tucked just on top the tank fuel filler tube the fuel will expand into the vent side of your fuel sight gauge unless the tank has a vent lower than the sight gauge vent. No matter what you do, on takeoff, the fuel still can slosh and fill your sight gauge vent side (especially in a mono). Your fuel flow and wrist watch is all you have for sure. Best Regards, Bud Yerly Custom Flight Creations Tech Counselor www.customflightcreations.com -------------------------------------------------- From: "willydewey" Sent: Saturday, December 27, 2014 2:53 PM Subject: Europa-List: Warping or shrinkage of fuselage around and below fuel fille > > I have seen some severe distortion in the skin below the filler cap on a > TRI gear and would welcome independent advice why it happened and what > method of repair is recommended for a permanent repair? > > -------- > Give a wise man knowledge and he will be yet wiser > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=436326#436326 > > > ________________________________ Message 2 _____________________________________ Time: 01:01:39 PM PST US Subject: Europa-List: Re: Warping or shrinkage of fuselage around and below fuel fille From: "willydewey" hi GUYS MANY THANKS FOR A FULL AND FRANK REPORT ON THE REASONS AND METHODOLOGY FOR A REPAIR OF MY WRINKLED OUTER SKIN. THE PICTURES WILL ASSIST IN MAKING THE REPAIR. I HOPE TO GENTLY USE A HOT AIR GUN TO HELP IRON OUT THOSE PESKY CREASES WHICH I CANNOT LIVE WITH. I WILL LET YO ALL KNOW HOW I GET ON , BUT THANKS ONCE MORE BILL -------- Give a wise man knowledge and he will be yet wiser Read this topic online here: http://forums.matronics.com/viewtopic.php?p=436369#436369 ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message europa-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/Europa-List.htm Web Forum Interface To Lists http://forums.matronics.com Matronics List Wiki http://wiki.matronics.com Full Archive Search Engine http://www.matronics.com/search 7-Day List Browse http://www.matronics.com/browse/europa-list Browse Digests http://www.matronics.com/digest/europa-list Browse Other Lists http://www.matronics.com/browse Live Online Chat! http://www.matronics.com/chat Archive Downloading http://www.matronics.com/archives Photo Share http://www.matronics.com/photoshare Other Email Lists http://www.matronics.com/emaillists Contributions http://www.matronics.com/contribution ------------------------------------------------------------------------------------- These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.