Doesn't the sport pilot stuff have a radius from home restriction? Bobby
> Brian: > > My biggest concern was weakening the wing by cutting into it. I am also > toying > withe the Idea of a "Bladder Tank because the tank would collapse as the > fuel > was consumed whch should reduce the tank venting issue. My goal is to > reduce > the fuel in the cowl header tank to about an hour and have the rest in the > wings. > > How did you reinforce the wing to make up for opening the wing? I feel > also > that a properly designed bladder tank would require a much smaller opening > which > should be a plus but fuel "slosh from lack of "baffles" could be an > issue. > > I am taking over a KR2 project that was being built as a Tr-Geared bird > and is > on its main gear. It needs Fire-Wall Fwd, Nose Gear ass'y and cockpit > fit-out > pait and finish. I intend to do all that I can to get it under > sport-plane > limits so it will have a smaller engine in it to keep the Speed down. Max > fuel > load will be kept to no more than 21 gallons usable but not less 5 hrs > range. I > want it for cross country use from my midwest location to Yuma in the west > and > Raliegh Durham in the east. Shoud make for cheaper travel than by car and > a > whole lot quicker. I am a Pvt Pilot with over 300 hours but at age 63 > will just > convert to a sport pilot. > > Don > > Brian Kraut wrote: > >> I retrofitted them in the stub wings at the same time that I converted >> from >> the retract gear to fixed gear. It wasn't terribly hard and doing it on >> the >> outboard wings should be easy also. Basically here is what I did: >> >> Cut a rectangular hole on the bottom side of the wing between the two >> spars. >> Use foam sheet about an inch and a half thick aginst the spars and on >> the >> inboard and outboard side of the hole you cut. You basically want to >> make a >> box in the wing and leave a lip around it that is flat and about 3/4" >> below >> the bottom surface of the glass on the wing. Carve some of the foam out >> of >> the wing top sheet to give yourself a thickness of about 3/4" on the >> foam. >> Use some instant expanding foam to give yourself somewhat sealed corners >> and >> make them a little rounded. >> >> Now get a flat sheet of 2" foam a little bigger than the rectangle you >> cut >> out and glass one side of it with three layers of glass. Lay it upside >> down >> on a flat smooth surface with bagging film or plastic sheet on it and >> put >> some weights on it so when it dries you peel off the film and have a >> foam >> board with one side of smooth flat glass. Trim this piece so it is >> about an >> eighth inch smaller than the hole in the wing all the way around. Wrap >> it >> with bagging film or plastic wrap. >> >> Now cut yourself three layers of glass to fit each of the bottom and >> sides >> of the box hole in your wing. Make them all a little big so they >> overlap >> on the edges and make the side pieces tall enough so they wrap over the >> flat >> lip you left on the side pieces. Also cut a bunch of pieces of about 3" >> strips for reinforcement on all corners. Glass all the pieces in >> overlapping and also putting the strips between each layer in the >> corners. >> >> When it is all in you will have the glass folded over the lips around >> the >> box. Get a good amount of epoxy there and then lay in the foam and >> glass >> rectangle that you made and wrapped with the plastic. Put some weight >> on it >> around the edges. When the tank dries you will be able to pop this >> piece >> out and the lip on the tank will be nice and flat and fit the >> rectangular >> cover. >> >> Now trim about a quarter inch additional off of the rectangular piece. >> Sand >> the edges of it and the lip on the tank for a good bond and then epoxy >> it >> in. You should have at least a half inch of contact area between the >> surfaces. Put weights on the edges then pour some epoxy about a quarter >> inch deep around the edges to get even more of a seal. This is why you >> trimmed it again to make yourself the epoxy moat. >> >> When it is all dry you can fill in the gaps with expanding foam, sand >> your >> rectangular cover foam to match the wing, and put on another two or >> three >> layers of glass overlapping the original glass on the wing. >> >> I did leave out a few steps like putting in the fuel lines etc. Make >> sure >> you have some kind of screen on the end of the line. I also carved a >> concave well in the front inboard side of the cover where the fuel line >> pickup would sit and one in the rear inboard corner where I epoxied in >> an >> aluminum welding flange for the sump drain. I also epoxied in one of >> the >> plastic fuel caps that Great Plains sells before I put the bottom cover >> on. >> >> I used a good bit of expoxy on the inside of the box and still had some >> pin >> holes so I sanded it down then used a brush to paint on a good wet coat >> of >> epoxy and let that dry to get it sealed. Since the bottom cover dried >> against the smooth bagging film it didn't have any pin holes. >> >> Good luck. This process is a whole lot harder to describe than it is to >> do >> so if you don't get something I am saying just ask. >> >> You can also cut the hole in the top of the wing, but it is much less >> flat >> and will be a lot harder to make the cover for and have it seal against >> the >> rest of the tank. >> >> I used three layers of glass in the tanks. Mine were only 5 gallons >> each. >> If you are making them bigger you might want a little more glass at >> least on >> the bottom and sides. >> >> Brian Kraut >> Engineering Alternatives, Inc. >> www.engalt.com >> >> -----Original Message----- >> From: krnet-boun...@mylist.net [mailto:krnet-boun...@mylist.net]On >> Behalf Of D F Lively >> Sent: Thursday, March 09, 2006 9:48 PM >> To: kr...@mylist.net >> Subject: KR> Retro-fitting Wing Tanks >> >> KR Builders. >> >> Has anyone retrofitted fuel tranks in the outboard wings? What about >> "Bladder Tanks"? >> >> Don Lively >> riksh...@interl.net >> >> _______________________________________ >> Search the KRnet Archives at http://www.maddyhome.com/krsrch/index.jsp >> to UNsubscribe from KRnet, send a message to krnet-le...@mylist.net >> please see other KRnet info at http://www.krnet.org/info.html >> >> _______________________________________ >> Search the KRnet Archives at http://www.maddyhome.com/krsrch/index.jsp >> to UNsubscribe from KRnet, send a message to krnet-le...@mylist.net >> please see other KRnet info at http://www.krnet.org/info.html > > > > _______________________________________ > Search the KRnet Archives at http://www.maddyhome.com/krsrch/index.jsp > to UNsubscribe from KRnet, send a message to krnet-le...@mylist.net > please see other KRnet info at http://www.krnet.org/info.html >
