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Plastic wheel can't enter in a servo shaft


Hi, mi name is Adolfo from Mexico, and I bought 4 wheels 2-5/8" plastic Yellow wheel Futaba servo hub (https://www.pololu.com/product/228).

In the wheel descriptions says that it can match with Futaba servo splines such as the continuous rotation servo Power HD AR-3606HB (https://www.pololu.com/product/2149); but I was looking for a Standard servo, so I read in the servo descriptions that if want a standard servo with same sizes, the Power HD standard servo 6001HB is the option (https://www.pololu.com/product/1056/resources).

At the end, I bought 4 Power HD Standard Servo 3001HB (https://www.pololu.com/product/1058) because in the datasheet of the three, servos the Horn gear spline specifications are the same (25T/5.80).

So my question is ¿Why the shaft of my servos can’t match with the wheels if according to the datasheet the Power HD AR-3606HB, the Power HD standard servo 6001HB and the Power HD Standard Servo 3001HB have the same spec? ¿Or perhaps there is a mistake in your web site info?

I hope answers, thanks and have a good day.


Hello, Adolfo.

It sounds like you are having trouble mounting your wheels to the servo horn. Is the fit too tight or too loose? If you are finding the fit too tight, you might try placing the wheel over the spline and then using the screw to force the wheel onto it.

- Grant


Yes, it was too tight, so I tried to force the wheel with the screw as you recommended, and I did it.

But I still thinking that the measure is not the correct because the wheel suffered a plastic deformation in his union when it was forced with the servo spline.

Before forcing the wheel, I measured diameter of the circle join of the wheel against the original servo tool included, and there is a difference of 0.20 mm.

Have a nice day.