View Full Version : Too much servo travel - servos twist main shaft!
avalys
11-15-2007, 08:33 PM
I just finished reassembling my Blade CP Pro after a bad crash. Everything is a plastic part except the swashplate, which I replaced with an aluminum part from E-Flite.
I have adjusted it properly for -10 to 10 pitch range (I think...), and changed nothing else (the servo horn holes in use are the same), but now at max aileron deflection (left and right) the servos overdrive the swashplate (travel too much), to the point where the whole frame is twisted to one side.
What could be going on?
=-C°G-=
11-17-2007, 12:05 AM
Got any more detail? If the frame is actually twisting something is seriously binding. Its a fairly rigid component in general.
Are you sure there are no cracks in the frame?
I've been looking at mine and I can't see where I could actually get the swashplate to bind that bad. The servos don't move that far. :)
Can you supply a pic? (as they say...a picture is worth a thousand words.) :)
avalys
11-17-2007, 01:49 AM
Well, I guess I described it wrong - it's not really the frame twisting, but if I hold the heli by the tail boom, and I give it full left/right cyclic, the main shaft is pushed over slightly in that direction.
carlo_the_wonder_frog
11-17-2007, 09:02 AM
Check that the frame is not cracked around the mainshaft bearings, or that the main shaft bearings are still in place. The servos should not be able to tweak the mainshaft at all.
=-C°G-=
11-17-2007, 09:17 AM
Well, I guess I described it wrong - it's not really the frame twisting, but if I hold the heli by the tail boom, and I give it full left/right cyclic, the main shaft is pushed over slightly in that direction.
If you hold the frame and grab the head with your other hand. Can you move it side to side? Forwards and back? There should not be any play in the mainshaft. If so, like carlo indicated, look for cracks in the frame/bad bearings/ poorly seated bearings etc.
Good Luck! :)
EatMorePizza
11-23-2007, 03:17 PM
Mine does the same. I believe it started when I also changed the swash. It actually pulls the main shaft and twists the frame. It really only happens durring full cyclic since I dont use full cyclic I lrft it alone for now. What I will do soon is move the link rods on the servo horn closer so it has less travel.