Rhumba555
02-20-2007, 06:01 PM
Well, as an update to my last post about the HDX300 build and the problems I was having, and after a couple more mods I got the bird in the air and she actually hovered (as well as I can make her hover anyway). I will post a video when I get time.
One of the mods that really helped was to install 2mm screws up through the main gear and have them go into pre-drilled holes in the tail drive pulley to make it a more positive drive for the tail. The tiny set screws that were in the tail drive pulley were contantly slipping and I just couln't get them tight enough to hold for any length of time. I know that this will eliminate tail response in an auto but I'm not doing autos yet and I will have a Trex by then. (and will be a better pilot). The other mod was to replace the solid carbon tail servo pushrod that was designed for the cnc tail with one made from a carbon tube with ball links attached to the ends. This is MUCH stiffer and does not buzz under minor vibration.
One other mod that fixed a binding issue in the CNC head (Blade TX) was to Dremel about .050" chamfers on both sides of the slot in the anti-rotation bracket. The fit of the pin into the stock bracket is very close and since the pin is not on center of the swashplate's rotation in cyclic moves, it binds in the AR bracket during cyclic/collective inputs. Basically I allowed the pin a little more angular freedom by making the walls of the AR bracket thinner.
Anyway, I was not about to allow this little heli to get the best of me. I figured it is just a smaller Trex and it should fly fine once all the bugs are worked out. Although I have never owned a Trex, I'll bet when I get one I will notice that Align worked out all the bugs that I had to on the HDX300.
Well that's it for now. Let me know if you have any questions or comments. Happy hovering!
One of the mods that really helped was to install 2mm screws up through the main gear and have them go into pre-drilled holes in the tail drive pulley to make it a more positive drive for the tail. The tiny set screws that were in the tail drive pulley were contantly slipping and I just couln't get them tight enough to hold for any length of time. I know that this will eliminate tail response in an auto but I'm not doing autos yet and I will have a Trex by then. (and will be a better pilot). The other mod was to replace the solid carbon tail servo pushrod that was designed for the cnc tail with one made from a carbon tube with ball links attached to the ends. This is MUCH stiffer and does not buzz under minor vibration.
One other mod that fixed a binding issue in the CNC head (Blade TX) was to Dremel about .050" chamfers on both sides of the slot in the anti-rotation bracket. The fit of the pin into the stock bracket is very close and since the pin is not on center of the swashplate's rotation in cyclic moves, it binds in the AR bracket during cyclic/collective inputs. Basically I allowed the pin a little more angular freedom by making the walls of the AR bracket thinner.
Anyway, I was not about to allow this little heli to get the best of me. I figured it is just a smaller Trex and it should fly fine once all the bugs are worked out. Although I have never owned a Trex, I'll bet when I get one I will notice that Align worked out all the bugs that I had to on the HDX300.
Well that's it for now. Let me know if you have any questions or comments. Happy hovering!