I used a 1 1/2 inch strip of fiberglass covered with 30 min epoxy diluted with a little rubbing alcohol, all the way around the center rib. This is on top of the 30 minute epoxy I used to put the wing together. I've crashed this thing a few times and so far have only had to repair the leading edge(besides replacing the fuselage, but that's another story). That will help a whole lot. Of course, you can always use a wider strip, but that's what I had handy.

I also had to add about 1 1/2 oz of sticky lead weights (the kind you get for pinewood derby cars) to the after section of the Fuse, just below the horizontal stab. I superglued them to the fuse after removing the monokote from the area. I didn't want to try and fool around with moving the battery pack back, but with my new kits, I try to do that first. It flys fine with this bit of weight.

To balance it, you can either buy a CG machine from your LHS or online, or if your handy, a piece of 1X4 two new pencils and the funny looking triangle erasures on them, and you can make your own, for next to nothing. You can find the plans in a book that's usually available at the library, written by the folks at MAN called "Radio Control Airplane Building Techniques. I got a lot of good information out of that.

Good luck!

Don