I'm trying to create a centre section for a 3 piece body, I've cut it from the sycamore log that I have,but fot the life of me I cannot get the edges right,I can't get 90 degree angles,I've planed it,I've used a surform,I've tried putting sandpaper on a flat surface and trying to square it off with that which created good flat edges but at slight angles which would obviously throw off the other sections when tryin to glue! Can anyone help because this is driving me crazy!