Great Thread! When I built the balsa Nova. The plane from hell!! I had it all togther except for cutting the cowl. I decide to use a hole drill bit to drill out for the cylinder. I held to cowl up to the cylinder and told myself "remember to transfer the measruements to the opposite side". Marked the cowl, Started Drilling! But of cousre not the opposite side. Had to patch it and repaint it. Then of course took it to the field for the maiden filght and took off with the ailerons reversed and crashed, but me, never have I made a mistake. Well at least not the same mistake twice!!