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Tarkers
06-08-2007, 09:21 AM
Hi All,

I'm having a few problems getting airbourne following a re-build and wondered if the knowledge base that is Helifreak could help me out (again!!).

OK, so I've re-built my head, replaced all the broken bits including the boom, main shaft, blades, etc, messed around with the settings on my Tx (with the help of my LHS) but now have a scarey type of situation :badair: :

I'll spool up (with the usual Swift Shakes) to mid stick where I'm at zero pitch (My throttle curve is linear 5pt 0,25, 50, 75, 100 and my pitch curve 0, 35, 50, 65, 100), everything is fine.

A little bit of right yaw (mode 2 left stick to the right) gives the correct nose to the right reaction (left gives the same correct reaction) then as I move into a positive pitch and the Heli goes light on it skids and I'm about to get airbourne, I'm getting maximum yaw and the Heli spins on its axis (pirouette - I think its called) at a massive rate, almost going 270 before I can react - I am also on grass so the friction on the skids is quite high until the heli is light.
Fortunately the Heli is stable from point of view of collective, so my new SAB blades and CNC head are all still beautifully intact, but sadly unused at present :shock:

I haven't adjusted the Gyro, a 401 running at around 75 delay (I'm still learning) and my EPA on my Tx shows 45% for Ch5.

Any ideas whats going on? Like I say I have fiddled with quite a lot, the boom has been off, which meant removal of the servo and the connection to the Rx. I've tried reversing the servo, reversing the witch on top of the Gyro, reversing both (!) :arggg: , reversing the the Ch5 in the Tx, nothing is having any effect!

What am I missing :dontknow

JustPlaneChris
06-08-2007, 11:31 AM
It sure sounds like a "reversal" issue, either gyro or servo. You didn't somehow reverse the rotation of your tail rotor? I haven't built my Swift yet, so I don't know if it's easy (or possible) to flip the belt when reinstalling the tail boom like it is on a Rex, but if that's what happened, and your tail rotor is spinning in the opposite direction....?

Sorry, just grasping at straws. :)

-Chris

Tarkers
06-08-2007, 01:45 PM
JustPlaneChris, and everyone else in fact,

...ermmm, ahem, :oops: where's the bit on this forum where you crawl under a rock and pretend no-one can see you...?

Just twigged bout an hour after I posted that that's exactly what I did. Rear rotor belt twisted the wrong way, giving a reverse of whatever input or corrective solution I made.

Sorted now and just completed the first flight with new CNC head and blades - Swift flies smooth as a baby's bum, LiPo's on charge ready to go again - man I love this hobby! (except when I'm making an arse of myself on a frequently visited International Forum :oops: :roll: Hey, we all make mistakes - just wish more of mine were as easy and inexpensive to sort as this one!! :lol: )

Have a good weekend all,
Tarkers

JustPlaneChris
06-08-2007, 01:57 PM
Tarkers, I'm glad to hear it was so simple! And um.... the only reason I suggested the belt twist is because I've done it too. :lol:

I really need to get some other projects out of the way so I can build my Swift!

-Chris