I think of 2 angles as important. The first angle is the angle of the front wing to the board (Or fuselage, since fuselage is usually square to mast and mast square to bottom of board). All you want here is for the board to not be pointing up or down comedically at cruising speed. For your front wing the angles of attack range from 11.5 degrees at 12.5km/hr, 0.7 degrees at 24 km/hr and -1.1 degrees at 35 km/hr. You are likely to be spending most time cruising in the top half of speed range (from the lowest drag dip and faster). So I would say setting front wing at 0 degrees to fuselage should be just fine.salvatoreone wrote: ↑Sat Oct 17, 2020 9:52 amOh beautiful! Yeah, I think I'll go with the thicker option so SG6041. Is the front wing at 0° AoA relative to the fuselage? I know that stab is usually at negative 1-3° but I'm not sure about the front wing.
I was thinking about printing the mould but I'm a bit worried this will be more difficult to laminate than 3D printed foil. I think I'll go with the easiest way for my first foil but I already have some ideas I want to try out later such as making a mould for expanding foam which will later be laminated... I'm sure someone has already done it.
NICE modeling. That looks great!salvatoreone wrote: ↑Sat Oct 17, 2020 11:02 pmOkay... So this is the result of few hours in Fusion360. I might have gone a little too ambitious with the front profile - I copied it from online pictures of Slingshot Infinity 76 wing but I think the final product will need to be simplified. Other than that I think that's a beauty! This is SG6041 airfoil profile, anything thinner would be too thin I think.
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3D printing the core is definitely easier. If you want to have it match the NACA profile then you will need to subtract your layup thickness in advance. To get closed cells I use cubic infill on prusaslicer.salvatoreone wrote: ↑Sat Oct 17, 2020 9:52 amI was thinking about printing the mould but I'm a bit worried this will be more difficult to laminate than 3D printed foil. I think I'll go with the easiest way for my first foil but I already have some ideas I want to try out later such as making a mould for expanding foam which will later be laminated... I'm sure someone has already done it.
Hand layup should be fine. But would be easier to get 200 g.m^2 fibreglass to conform than carbon fibre. For Fibreglass I would probably go for 8 or so layers of 200 g/m^2 S-glass. And yes it might be best to do a handlayup wing first before adding complexity of vacuum bagging. I'm just a big fan of the consistent good results vacuum bagging gives.salvatoreone wrote: ↑Sun Oct 18, 2020 12:11 pmIf it was only $50 I would be all in, but I don't have any pump to actually make the vacuum so unless there is some workaround I'll need to stick to handcrafting...
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