RE: Draganfly iv. Anyone flew it?Control?
Laminating Rotors
Howdy Moe. I was very tired of clipping blades while in flight as well. DFI recommended that I use packing tape to reinforce the blades. However, they said that I should only apply it to the bottom. Well, I did that and cut the tape to perfectly fit the contours. Then, I thought of the fact that over time and with temperature changes and blade flexing that eventually the edge of tape is going to slightly begin to separate from the blade surface allowing air to be caught between the tape and the wing surface. This would cause drag and affect performance. So, the solution was to get some 3" (minimum width) clear, thin packing tape and just cover the top and bottom of the blade with the closed end of the sandwich on the leading edge and the opened end on the trailing edge. Actually when you fold the tape over on itself, it sticks together quite well at the trailing edge, even after trimming it down to contour the blade. So, with this method, the leading edge is not succeptible to separation. I did this seperately for the left and right of the blades and covered the middle section with a single layer to each side. Any more than 2 layers in the center increases the thickness of the rotor thereby shortening the nylon bolts penetration into the rotor head gear. I let these sit overnight to see if there was any separation and there was some slight bubbling and separartion but mostly near curved areas. I just took a pin and popped the bubbles and that fixed them but I have had to make some small cuts to relieve the stress of the tape in the curved areas. The blades look really nice and are very smooth but it just takes too long to do. I also noticed that the wind noise was much quieter because of the smoother finish of the blade surfaces. I bet they will be more efficient too. I think the standard blades' texture is just too rough for maximum efficiency, especially the sanded leading edge, and just have to create more drag than desired as they are. I am definitely going to be investing in carbon fiber blades soon.