stacks of model aviation magazines (or similar) make great, form fitting weights.<div>"single" socks about 3/4 full of navy beans work too.  These socks can also be used as extra hands, fuselage cradles etc.  just keep dry!  If you get the canvas bags that sports shops sell for reloading shotgun shells, don't use the lead shot, it will dent your balsa all to hell....don't ask.....I have one wing that the sheeting looks like a golf ball.</div>