So with Mark on vacation in the Florida Keys...it was time to fix my stuff. With that said...
I started out with the Rave in the hopes that bearing noise was finally gone. It was! And...Oh the horror! I ordered a new bearing set for my O.S.105HZ from RCBearings (good thing I did!). When I removed the main bearing, it became obvious as to where all the noise was coming from! The main bearing was totally shot. Heavy pitting all around the inner race, and some on the outer. It was the inner that was giving me the noise issues. Had I continued to run the motor that way, it would be a matter of a few more flights, and "bam," time to order a new motor!!!
Now my Rave is purring like it should. I put 3 flights on it, and boy was that ever a treat! I need to do a little tweaking with the collective pitch, as the plus side seems weak, and possibly a bit more aileron response. Other than that, its good to go!
Next up was my new Synergy N7. Ok, it is still a nightmare to fly, but I think I figured what's going on with this heli! Its in the links! They are so tight that the Spartan Vortex VX1n controller is having an issue with it. At first I thought it was the cyclic gain being too high…nope. Then I thought I had dialed in some "sub trim" in the menu…nope. And I thought the aileron tilt problem was only in idle up 1&2…and again, nope, that wasn't it.
So with no distractions and spectators watching…its time to figure out this problem I'm having, once and for all! Well, actually there were 3 people watching somewhat. A mother and her two children were walking the school grounds and would walk past me…from time to time, but not just standing there to watch me fly!
First flight, I lifted the N7 off the ground and placed it into a hover. I let it sit there a bit to watch it. Then I moved the aileron stick a little to the left and right quickly to see how it would react. It seemed to be fine, but then it started to happen…it twitched all by itself to the left, ok… I flew it around the field a couple of times to see how it would respond. A couple of times it moved itself to the left, and I would correct it. Then I tried idle up 1, it didn't move when I switched into idle 1.
Ok, so a couple of more laps around the field. Everything seemed good for the time being, but it didn't take long for it to start acting up and making aggressive moves all by itself! Wow, this is interesting! I tried idle 2 and it seemed to settle down some. So a few more laps around followed by some hammer head turns. However, the rudder is responding better! A couple of aileron rolls, and WATCH OUT! Man those are lightning fast!!! Ok, mental note, turn down the aileron roll rate!
One more lap around and oh, oh! The clutch let go! I know that feeling all to well. Ok, switched into throttle hold and head back towards me. However, it became a battle with the ailerons as the VX1n controller wanted to over command the ailerons...the dreaded roll over! Oh no you don't! I managed to fight it quickly without panicking (but lost head speed in the process), switched into normal mode and switched out of throttle hold (all this in a blink of an eye...muscle memory at this point!). Thankfully the clutch caught and began spooling the rotor head back up in time to avoid smacking into the ground…saved it!
I brought the throttle to idle and let it sit for a moment, then throttled up and returned the heli close to where I was standing. As it was hovering, that's when I noticed the swashplate seemingly fighting the tightness of the links. I experienced this before with a newly built heli, but it normally goes away in a few flights…not this one! Because of the cold weather, it would take many flights to break them in. The warmer/hotter weather would have made this task faster as the plastic links would have stretched some, or just enough. Then with many more flights, the exhaust gasses would have acted as fine sandpaper (a rubbing compound) and formed them to the balls. Well, that's my thought on this subject.
I also noticed, through the mist of everything else, the collective pitch sensitivity has changed quite a bit. I set the total pitch range to +/-11 degrees, now it feels a bit sluggish. Ok, so I'll set it to +/-12 degrees. The 11 degrees made a difference in the collective "pop" feel, it did change the resolution of the pitch range. The collective stick is no longer touchy!
So later today and after 4 flights, I popped all the links off and ran the Botos link sizer through them again. This time making sure they are a lot smoother. However, I found that I damaged the large sized link ball with my link tool/pliers. It flattened the cutting surface some...great! NOT! Ok... Ah, umm, not sure if this will work...but I tried the heat method. I snapped the link sizer in the link and used my Bic lighter to lightly warm the link. 3 fast passes with the flame and several turns both direction...whoa la, almost perfect!
My N7 is ready for yet, another flight!