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Aerofoils and Curves in Depron Having recently returned to Indoor model flying after a gap of some 15years I have been amazed by the advances in materials and technical items available. As it have been over 40years since I built a stick and tissue model I decided to build with the new Depron material, building the fuselage was fine but forming the wing was not so easy, I tried bending over a curved table edge, baking over a mould in the oven, and wrapping around a tube with bandages and immersing in hot water, none of these were successful, the best results were the bandage trials but not perfect. After messing about with various ideas I came up with the following system. I found a long tin 270mm long ( 10inches ) X 75mm Dia ( 3inch ) , I cut a 8 x 10mm hard wood the length of the tin and cut a 2 x 2mm rebate in one edge and used epoxy to glue this to the tin, ( see attached sketch) , Cut the wing to desired length and cord, if using 1mm Depron use a 1mm packing piece to ensure the wing is tight against the tin surface ( packing not required if using 2mm Depron )Fill with Hot water and wearing suitable gloves ( I use thick gardening ) slowly bend the depron around the tube until you get the desired curve, hold for about 30 seconds and remove from tin . Using the method I have formed several wings from 50mm cord to 100mm and 500mm to 600mm span. If you do not have a suitable tin you can use copper pipe etc provided that you can seal one end, a larger dia will produce a smaller curve and a smaller dia will produce a larger curve. You will need to experiment to obtain the aerofoil you require, I have found this method to be quite easy to produce good profile wing sections. WARNING, THIS METHOD IS DANGEROUS, ENSURE NO ONE IS AROUND YOU WHILE DOING THIS.
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