silent 3 bladed prop - I got the equation curves down in inventor.

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Uppdate 29.11.15 Added 9X4.5 blade sett, (Prop4) i hadent done this for a while so i hope i got it right. I finally got the equation curves in inventor all set, if somone wants a spesific airfoil profile let me know. This has less tip turbulence and makes a lot less noice I use it as a silent replacement for 5-7" props for my quad. 3 mm axel print as solid. I print it on hight resolution and treat it with acetone vapour I have upploaded an inventor file with a naca profile equation curve, feel free to make any wing profile by simply tweeking the numbers. Instructions Equation curve in inventor. thickchordt5(0.2969sqrt((1 in)/chord)-(0.1260t1 in)/chord-(0.3516t^31 in^2)/(chord^2 )+(0.2843t^51 in^3)/(chord^3 )-(0.1015t^7*1 in^4)/(chord^4 )) where: • c is the chord length, • x is the position along the chord from 0 to c, • y is the half thickness at a given value of x (centerline to surface), and • t is the maximum thickness as a fraction of the chord (so 100 t gives the last two digits in the NACA 4-digit denomination). You need to add chord and thick as variables in inventor (the fx button) before compiling the equation curve, PS ! The part file mustbe in inches!!!!!! The foil must be made in 2 sections one for the top curve and one for the lower just add "-" in front of the lover airfoil curve.