by mtaylor » Sat Oct 24, 2015 11:19 am
90 deg. leading edge. There are no compound curves till out at the tip bow, so 45 deg. is only used there. Even with 45 ply I couldn't get my leading edge ply to completely comform to the leading edge tip bow/ spar/end rib triangle so I glued the triangular piece of ply to the leading edge following the curvature of the tip bow ply, to the rib at the beginning of the tip bow, and to the spar as it works it's way from the leading edge wing tip up towards the end rib (forms a triangle). Halfway between last rib and where the spar meets the tip bow, I cut a wedge slit in the ply to get rid of where the skin wanted to pooch out. Cutting out that triangular slit allowed the skin to lay flat to the spar then I glued a piece of ply to the underside of the slit area and, after the glue set, I sanded through the top ply skins and into a bit of the bottom ply I glued on underneath. That allowed me to "round" out that last bit of compound curve that I was trying to get out of the ply. Sort of faking it. Hope this paints a picture that you can see in your mind. Hard to put into words, but, hope it helps.
90 deg. leading edge. There are no compound curves till out at the tip bow, so 45 deg. is only used there. Even with 45 ply I couldn't get my leading edge ply to completely comform to the leading edge tip bow/ spar/end rib triangle so I glued the triangular piece of ply to the leading edge following the curvature of the tip bow ply, to the rib at the beginning of the tip bow, and to the spar as it works it's way from the leading edge wing tip up towards the end rib (forms a triangle). Halfway between last rib and where the spar meets the tip bow, I cut a wedge slit in the ply to get rid of where the skin wanted to pooch out. Cutting out that triangular slit allowed the skin to lay flat to the spar then I glued a piece of ply to the underside of the slit area and, after the glue set, I sanded through the top ply skins and into a bit of the bottom ply I glued on underneath. That allowed me to "round" out that last bit of compound curve that I was trying to get out of the ply. Sort of faking it. Hope this paints a picture that you can see in your mind. Hard to put into words, but, hope it helps.