As Mark said, you won't hve any stifness with just glass, unless you did a piece 1/8" thick which you could never fair correctly. I would glue in a piece of 2" foam and glass over it.
I am assuming that the reason for trying to do it some other way is because the plane is not upside down. You should be able to glass the foam upside down if you put two layers of glass and epoxy on somethink like thin masonite with bagging film on it then stick it up to the foam surface you have already prepared. You will need something to hold up the masonite in place. Figure that out before you start the glass and epoxy! Something you can blow up to keep even pressure on it like a raft might work O.K. I did some upside down glassing on the tops of my wing while the plane was upside down. I was able to use bagging film stretched tight and held on with tape. ---------- Original Message ---------------------------------- From: "Mark Langford" <[email protected]> Reply-To: KRnet <[email protected]> List-Post: [email protected] Date: Fri, 9 Apr 2004 15:10:00 -0500 >Scott Bailey wrote: > >> My question is that since the underside of the wing (between the spars) >> is essentially a flat area, could I lay up a fiberglass "sheet" on a >> table that, once dried, could be cut to fit and bonded as done with >> wing skins? That way, it seems that the need to "refoam" the wing >> could be dispensed with. Comments? > >I don't think I'd do it that way. A layer or two of fiberglass has just >about no stiffness to it without some foam underneath. I think you could >almost count on it deforming just due to airloads. It's awfully easy to >stuff some foam in there and sand to shape, or use some 2 part urethane >poured into the holes (if the thing is upside down) and then sand to shape. >Or if it's right side up, you could use sheet foam and 2 part urethane to >hold it in place. You're going to need to rough up the area around the hole >anyway, and you'd be doing that as you sanded the foam to conform to the >airfoil shape. > >Mark Langford, Huntsville, Alabama >N56ML "at" hiwaay.net >see KR2S project at http://home.hiwaay.net/~langford > > > >_______________________________________ >to UNsubscribe from KRnet, send a message to [email protected] >please see other KRnet info at http://www.krnet.org/info.html >
