highplummeter

i have futaba s3003, s28's, gws pico std, and a few other servos that refuse to turn automatically all the way around. they are all capable of 180 degrees, but only turn 60 to 90 degrees with my r114f futaba reciever and the servo tester on this webpage:
http://home.cogeco.ca/~rpaisley4/xServoTest555.html

also the problem is not that it is jammed inside, i can turn the servo by hand all the way around without it stopping until it hits the end.

guver

My Feedback: (325)

Mine all do that, I figured it was limited radio travel.

fizzwater2

My Feedback: (61)

90 degrees is about normal. I wouldn't worry. If you want 180 degree servos, you need to look at the various retract servos.

onewasp

I hope the OP was joking.

If not then RC may be in more trouble than I thought.

Bax

My Feedback: (11)

Servos typically have a 45-60 degree total movement. That includes going from one extreme with full trim to the other extreme with full trim. Generally, though, end-to-end travel when you move the stick from one end to the other is about 60-degrees or so. So your total end-to-end movement of the servo is up to 120 degrees. When the servo is disconnected, you can move it by hand through about 300-345 degrees or so, or from one mechanical stop to the other. It depends upon the servo. Because the full amount of travel is not needed in the vast majority of applications, and you want to be able to have a low amount of time from center to the end, travel is limited.

Also, because movement of the servo output is rotary, you get little linear movement of the pushrod if the servo moves much more than 60-detgrees from center...the remaining 30 degrees of rotation will produce very little linear movement for the time expended. This will introduce a lot of non-linear movement with respect to stickmovement, and amounts to inverse expo...with more pushrod movement in the center of travel, diminishing to nearly zero at the ends of movement.

About the only time you want a full 180-degree, end-to-end movement of the servo would be for a retract operation, where the total travel of the pushrod from one end of travel to the other is the only consideration you have. Speed is almost always never a consideration...in fact, slower is usually better for retracts, which is much more scale-like.

highplummeter

ok, thx, i was wondering whether or not it was my setup or not

Campgems

When you think of a servo. think linear movement, not rotation. Most of the linear movement is accoplished when the arm is 90 degrees to the pushrod. IE, 10 degrees of angle from the 90 degree point gives way more lnear movement than 10 degrees of angle between 50 and 60 degrees. When you get to the 80 to 90 degree from home, there is almost no linear movement at all. In other words, there is no pointin having a servo move more that 60 degrees unless you have a sail winch servo or a retract servo.

Don

nk3t

The travel of a servo is dependant on the pulse duration range the radio system or tester can output. You may want to look at the pulse stretcher from Servo City, which can enable 180 degree travel with many servos.


http://www.servocity.com/html/180o_servo_stretcher.html