450SA Swash set up

[uneverno]

So,
I finally think I understand the set up. Everything is moving properly according to the manual's directions for the control inputs:

(Swash is 120° CCPM)

Entire Swash moves up and down with throttle/pitch input. End points are ~1.5mm from Washout base at the top and shaft washer at the bottom, swash is neutral and centered on the shaft at mid stick (I have not set up throttle and pitch curves yet - swash was enough for one night .)

Aileron moves swash left and right appropriately, and Elevator moves it forward and back appropriately. No binding, and no interference at full travel with main gear, etc.

What I don't get is that setting it up was quite convoluted - I don't have the radio at (to for you folks on the other side of the pond) hand, so will fill in exact set up later, but it went something like this:

Aile and Elev servos reversed and at + 60% mixing, Pitch servo Normal and at - 60%. It took me some time to get it right - as I would reverse one servo, the swash reacted entirely differently than I would've expected it to - at one point (without changing servo channels) I had pitch working on the Aileron stick and stuff like that. All JR gear - 6102 radio, DS285 frame servos and DS3400 tail, and R790UL PCM receiver.

Does this sound like a normal transmitter set up? (actually strike that question)

What I'm really asking is: Does it make any difference what the Normal and Reverse servo settings are and +/- on the CCPM mix, as long as the swash is doing what it's supposed to?

Thanks,

[Aztek1701]

Hi Emil,

If the swash is behaving as expected, then your there. As far as I know, (and Ive got 4 well set up CCPM machines to back me up) Your right.. It doesnt really matter what servo gets reversed.

If its any help, the way I do it is to connect the whole thing up and then tell the TX that its 120 degree swash. Then I test the control functions... If on aileron I get the one aileron and the elevator, I swap channels at the receiver. Then I check again. If the now paired aileron servos both go in the same directions, I reverse one of them... Similarly, if the aileron and elevator servos go in the same directions, I reverse the elevator. Then I correct the direction of the movement with the mixing functions. At this point I make sure Im running a linear curve and set the stick to exactly 50% and I get the horns to 90 degrees by taking them off and turning them and as a last resort using the subtrims. At that point I then start adjusting the linkages to the swash to level it using a swash leveling tool. Once everthing is level I put the stick to 100% and check the level again. This time, I use endpoint adjust to bring the swash to level again. Next I move the stick to 0% and use the travel adjust again to level the swash. Once that been done, the swash will remain true pretty much throughout its travel. Then I go to work on the head and level everything there. IE mixing arms level ect. The end result is that at 50% with no trim you have 0 degrees pitch and at 100% you'll have very close to what the book says is maximum... Its simply a case now of using the pitch mixing to get it where you want.

What you get out the back of this is a machine that should fly right without trim on the first go.

Yes its a bit long winded of an explanation but I hope its of some use.

Take Care... Azzy

[uneverno]

Hey Azzy,
very helpful indeed. I haven't gotten to the head yet. I'm taking my time on the build because I want exactly that - a machine that's going to be as well trimmed as I can get it for its maiden voyage. I need to take the head apart regardless, as I've read that one of the faults in the 450SA build is that they forget to lube the O-rings on the feathering shaft.

I triple measured the servo links before I installed them, and although I don't have a swash leveler (getting one this weekend), it eyeballs very well. My elevator servo needed a minor amount of trim as the arm wasn't precisely lined up at neutral. Both other servos appear perfect (i.e. the splines co-operated

I discovered a weakness in my set up in that the rudder servo connector came loose from the Gyro, so fixed that last night. Where I'd placed the tiewrap to hold it down actually forced it loose. Better on the bench than in the air. That would've been fun