CCPM interaction

[Bobs]

Does everyone use a bubble balancer to eliminate CCPM interaction or is it unnecessary? Thanks.

[slo_dave]

I used this

http://www.readyheli.com/T_Rex_Swash..._p/leveler.htm

works perfectly and "to me", it is worth every penny.

[steve28]

i used my eyeballs

[Finless]

i used my eyeballs

[Bobs]

Finless, in one of your videos you used a bubble-balancer mounted on top of a paddle to eliminate the interaction in the CCPM and I was just wondering if that is necessary or if a swashplate leveler will do the same thing. Also, my previous T-rex (mechanical linkage) I was running a Mega 16/15/3 with a throttle curve in normal mode that had the motor running at 90 or 95 percent while just hovering. I'm using the same motor now and was wondering if I need to run the motor up that high just for hovering. Initially (a couple years ago) the consensus was that the motors ran cooler if they were run at high RPMs. Is that true or can I hover with the throttle curve at 70 - 75% instead? I also have a question about the canopy fit - or lack thereof, but I'll start a new post for that. Your videos have been extremely helpful, thank you.

[Finless]

Honestly onless you visually see thje paddles move around when moving the pitch stick from bottom to top then I would not worry about it. I went through the CCPM interaction thing in my video for completness only... The amount of interactions I had in the video you would probably not even notice.
Oh and the swash plate leveler is not accurate enough to show all interactions. Remember swash movement is amplifed at the top of the head (in the paddles) because of the mixer arms in the head arent 1 to 1. SO if your looking for perfection look at the paddles as that is where ANY interactions will show up... You may not see them at the swash. But again I think this is cutting hairs...

Bob

[Bobs]

Thanks, Bob, that's what I wanted to hear. I don't see any movement in the paddles. Any comment on running the motor at 75% instead of 90 or 95% just for hovering in normal mode? Here's what I have my pitch and throttle curves set at now: normal mode pitch is -4 5 10 with a throttle curve of 0 23 46 70 80 90 100 and that gives me about 75% throttle at lift off/hovering. Idle 1 should be okay with -10 0 10 for pitch and a throttle curve of 100 95 90 85 90 95 100. I should also mention that I'm running a 13T pinion with the Mega 16/15/3 motor which gave me plenty of power with my previous setup (mechanical linkage). Appreciate your opinion. Thanks again.

Bob

[Finless]

Of course that is a reduced head speed but as long as your not getting a wobble in hover or FF then should be OK... You do have a 10-15 increase when going from normal to idle up and I would be concerned of stripping the main gear with that much jump. Might want to up your normal just a bit.

Bob

[Rick Rotorhead]

Hmmm. I got some paddle wobble, but it just won't go. They actually move up and down a couple of times during each test in both ail directions and elev direction. If I get rid of ccpmi at full pitch, it still shows up at 3/4 pitch (bubble level at 0 stick). This is what Bob says we can use 'P mixes' to cure, but its all a bit too heavy going, so I'm gonna try it with the ccpmi just minimised as far as I can. In any case we're not talking big swings here, the TE of the paddle twitches up and down by maybe 1mm at most, so I reckon the helis natural instability will mask the ccpmi effects.

I too found that even when the swash leveler tool indicated no ccpmi, the bubble level on the paddles showed it up easily - funnily enough, just like what Bob said!!!!! Of course it helped the whole set-up procedure enormousley when I remembered to turn off (INH) the Hi-Lo Pit function assigned to a finger grip lever at the RH side of the Tx case

[Finless]

twitches up and down by maybe 1mm at most

I wouldnt worry about that much... you have more slop in your head than that!

I too found that even when the swash leveler tool indicated no ccpmi, the bubble level on the paddles showed it up easily - funnily enough, just like what Bob said!!!!!

Would I lie?

Bob

[Rick Rotorhead]

It is possible to watch the ccpm interactions even without a bubble level. If you watch the paddles very closely, you will see two givaways, first the trailing edge moves up and down and secondly if you observe the play of light reflected from the shiny paddle surface you will see the angle of the paddle changing as the pitch is raised and lowered. Thats my two penneth.

Quote: "I wouldnt worry about that much... you have more slop in your head than that! " U/Q

Yeah, thats what my wife says