Sidewayskiwi
OK folks
Thrust line offset
Still having fun with mig29V1 that pulls hard right
Its a pusher propslot
with motor running CW
Which way do I angle the motor to help it stop going right)?
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bogusbandit56
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OK folks
Thrust line offset
Still having fun with mig29V1 that pulls hard right
Its a pusher propslot
with motor running CW
Which way do I angle the motor to help it stop going right)?


If it pulls hard right there may be a warp or imbalance in the air frame, give it a good looking over.
In theory if the motor is running CW looking from the rear, it should pull left.
The motor needs to point in the opposite direction the plane is pulling.
Wot, no Depron?
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DualDesertEagle
Depends. Is ur motor in front of or aft of the CG? By "pulls hard right" do u mean it rolls or it yaws to the right?

If it yaws try putting washers between the motor and motor mount on one side. Which side that should be depends on where the motor is relative to the CG. If that doesn't help something's wrong with ur airframe.

If it rolls it can't be the motor. The worst thing a misaligned motor can cause is unwanted pitching and yawing, the latter MAYBE resulting in a little bit of roll due to one wing going faster and thus producing more lift than the other.
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Sidewayskiwi
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Depends. Is ur motor in front of or aft of the CG? By "pulls hard right" do u mean it rolls or it yaws to the right?

If it yaws try putting washers between the motor and motor mount on one side. Which side that should be depends on where the motor is relative to the CG. If that doesn't help something's wrong with ur airframe.

If it rolls it can't be the motor. The worst thing a misaligned motor can cause is unwanted pitching and yawing, the latter MAYBE resulting in a little bit of roll due to one wing going faster and thus producing more lift than the other.

It flies in a tight right bank under power
But glides beautifully straight so pretty sure its thrust line
What gets me is (as looking from the rear ) motor runs clockwise so prop torque means it should pull slightly left (like all my others )
If iam pulling right which way do I shim my motor in a pusher set up (motor behind cog)?
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bogusbandit56
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It flies in a tight right bank under power
But glides beautifully straight so pretty sure its thrust line
What gets me is (as looking from the rear ) motor runs clockwise so prop torque means it should pull slightly left (like all my others )
If iam pulling right which way do I shim my motor in a pusher set up (motor behind cog)?

When it comes to side thrust it is the same back or front mount. The thrust line should point away from the direction of the plane when it pulls off line.
Wot, no Depron?
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Wildthing
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It flies in a tight right bank under power
But glides beautifully straight so pretty sure its thrust line
What gets me is (as looking from the rear ) motor runs clockwise so prop torque means it should pull slightly left (like all my others )
If iam pulling right which way do I shim my motor in a pusher set up (motor behind cog)?

Then shim the left side of the motor. The other thing you could try just to see if it is with the motor alignment and if you have a reversed prop throw it on but be careful under power it may even pull harder right.
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Sidewayskiwi
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Then shim the left side of the motor. The other thing you could try just to see if it is with the motor alignment and if you have a reversed prop throw it on but be careful under power it may even pull harder right.

Yea been toying with this idea or putting a bigger prop or three blader on to get a bit more torque effect
For a KF4 profile parkjet this thing glides like nothing else straight as an arrow and float
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Sidewayskiwi
The other alternative is I suppose is activate the ailerons and feed a bit of left bank into it under power by mixing
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Wildthing
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The other alternative is I suppose is activate the ailerons and feed a bit of left bank into it under power by mixing

You are hiding the problem that way , also then when you go to glide it will role on you. Bigger prop and higher pitch will create more torque and make your problem worse. Reversing the prop to me is just a test but more then likely if the chassis is straight shim the motor. Do it Scott's way which is stupid easy, use tapered toothpicks, loosen off the screws a bit and wedge the toothpicks in. Tighten the screws and go for a test flight. If it's better but not enough loosen off the screws and wedge the toothpicks in farther. Just take your screw driver with you.
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jimbosflyin
Almost sounds like the verticle stabs aren't straight,rudders could trim and correct it.My $0.02
Parkflyers International 
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Grantman
Something is wonky. All of my propjets are built with a 0°/0° thrust offset and the most correction any have ever needed is a bit of weight bias to counter torque-roll, meaning I put the battery more to one side.
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jimbosflyin
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Something is wonky. All of my propjets are built with a 0°/0° thrust offset and the most correction any have ever needed is a bit of weight bias to counter torque-roll, meaning I put the battery more to one side.

Same here,I always check all angles even the naccels have to be at their equal shape and not worped.:cool_O
Parkflyers International 
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Sidewayskiwi
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When it comes to side thrust it is the same back or front mount. The thrust line should point away from the direction of the plane when it pulls off line.

Yea the way I got it straight in my head is looking at a thrust vectored fighter jet
Want it to turn left nozzle goes left (or prop centre)
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