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can't center the servo?

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I've had this issue for years. Gonna throw it out there. If the spline one the 3004 futaba servo is not centered for the Tamiya horn then how do I center the servo? Please tell me i have been missing something for 30 years. I can't understand why i need to trim my controller all the way over to one side.????

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Maybe centre it with the trim set the opposite way?

So when you trim it back to centre, it is centre?

Hope that made sense :lol:

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I guess the servo was centred with the TX you are referring to and using ? , as different TXs can make the servo centre differently , so if you centred it with one TX then used a different one then it might be off . Usually a spline might be off by a small amount hence having a trim setting,  but complete opposite is quite a lot   . Are the steering rods adjusted to specified lengths ? . Maybe a bit of rod tweaking and servo centring might do it . 

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It might just be me but it find the kit servo savers are always half a tooth out. Fit a high torque on and suddenly they are dead centre.

 

It could all be in my head though 🤪

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Generally, the procedure I follow is:

  1. Before mounting the steering servo in the chassis, connect it to the receiver and power the transmitter and receiver up.
  2. Center the steering servo stick/wheel.  99.9% of the time this is mechanically done via a spring in the transmitter so you just "let it go".
  3. Set the steering trim to the center position.  For analog radios, this means centering the trim lever.  For digital radios, this means clicking the trim button to the left or right until the LCD display shows that the center position has been reached.
  4. Install the servo horn on the servo according to the kit manual and try to get it as close as possible within the margin of error of the splines.  Yes, it may be slightly off from perfect center but let it go for now.
  5. Install the servo in the chassis and connect all steering linkages per kit instructions.
  6. Re-power the radio system to ensure the servo is still centered.   The act of installation often moves the servo off-center.
  7. Make note of how the front wheels aim.  Is it really bad, or pretty close?
    1. If it's really bad, double check that you measured the steering rods/turnbuckles correctly.   If they check out, then remove the horn from the servo and shift it one spline to the left or right and re-test.
    2. If it's only slightly off center, if your transmitter has a sub-trim setting, you can use that to shift the center point of the servo to the correct position.
      1. If no sub-trim is available in your transmitter settings, you can try to use regular trim.
      2. If neither trim has enough range to fix the problem, shift the horn one spline and try again.
  8. If none of that works, then you'll need to make mechanical adjustments to the steering rod lengths and live with mismatched left/right turning radii.
  9. Once you are happy with the center position, check the endpoints by going full left/right.  If your radio has it, use End Point / Dual Rate settings to prevent the servo from over-extending the steering and possibly damaging the servo from too much strain at full lock.
    1. To do this manually via mechanical means, choose a different servo horn hole closer or farther away from the center to adjust the throw.   You might have to drill a new hole in the horn to get the position closer to "ideal".   And if you are gonna do that, you can drill it closer to the "center" position you want as well.
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23 hours ago, Champ85 said:

Generally, the procedure I follow is:

  1. Before mounting the steering servo in the chassis, connect it to the receiver and power the transmitter and receiver up.
  2. Center the steering servo stick/wheel.  99.9% of the time this is mechanically done via a spring in the transmitter so you just "let it go".
  3. Set the steering trim to the center position.  For analog radios, this means centering the trim lever.  For digital radios, this means clicking the trim button to the left or right until the LCD display shows that the center position has been reached.
  4. Install the servo horn on the servo according to the kit manual and try to get it as close as possible within the margin of error of the splines.  Yes, it may be slightly off from perfect center but let it go for now.
  5. Install the servo in the chassis and connect all steering linkages per kit instructions.
  6. Re-power the radio system to ensure the servo is still centered.   The act of installation often moves the servo off-center.
  7. Make note of how the front wheels aim.  Is it really bad, or pretty close?
    1. If it's really bad, double check that you measured the steering rods/turnbuckles correctly.   If they check out, then remove the horn from the servo and shift it one spline to the left or right and re-test.
    2. If it's only slightly off center, if your transmitter has a sub-trim setting, you can use that to shift the center point of the servo to the correct position.
      1. If no sub-trim is available in your transmitter settings, you can try to use regular trim.
      2. If neither trim has enough range to fix the problem, shift the horn one spline and try again.
  8. If none of that works, then you'll need to make mechanical adjustments to the steering rod lengths and live with mismatched left/right turning radii.
  9. Once you are happy with the center position, check the endpoints by going full left/right.  If your radio has it, use End Point / Dual Rate settings to prevent the servo from over-extending the steering and possibly damaging the servo from too much strain at full lock.
    1. To do this manually via mechanical means, choose a different servo horn hole closer or farther away from the center to adjust the throw.   You might have to drill a new hole in the horn to get the position closer to "ideal".   And if you are gonna do that, you can drill it closer to the "center" position you want as well.

If I was getting a new servo saver for the stadium thunder, would you recommend small, mid size, or large kimbrough servo saver ? I have a savox 1258. The tamiya servo saver is also an option but the Kimbroughs I’ve heard are a bit tougher 

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8 hours ago, rwordenjr said:

If I was getting a new servo saver for the stadium thunder, would you recommend small, mid size, or large kimbrough servo saver ? I have a savox 1258. The tamiya servo saver is also an option but the Kimbroughs I’ve heard are a bit tougher

I don't have much experience with Kimbrough servo savers.  Looking at their website, they don't tell you what the differences are between the servo saver sizes.  If I had to guess, it would be the medium one based on pictures alone, but I'm not really sure.  Maybe someone else has more experience with them and could reply.

Personally, I would use the Tamiya Hi-Torque servo saver (part #51000) like @schuultzie51 did for his Blitzer Beetle: 

 

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4 hours ago, Champ85 said:

I don't have much experience with Kimbrough servo savers.  Looking at their website, they don't tell you what the differences are between the servo saver sizes.  If I had to guess, it would be the medium one based on pictures alone, but I'm not really sure.  Maybe someone else has more experience with them and could reply.

Personally, I would use the Tamiya Hi-Torque servo saver (part #51000) like @schuultzie51 did for his Blitzer Beetle: 

 

Thanks for your help!

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Good thing about the bigger kimbrough medium servo savers is that they have a spline adapter that goes on the servo first and then you mount the saver on that. It will allow you to make finer mechanical adjustments to get the saver on straight before you start messing with the controller. 

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