Servo Gear Stipped. Soon to be "model" wifes Cross Trainer

peter_dublin

Hi.

Just a quick question model owners might know, the servo on the wifes cross trainer died last week, gear stripped I believe, it still tries to turn but slips back once it reaches the stipped area and repeats over and over never getting anywhere, clicking as it does. It is possibe to replace this with a generic servo, i.e. would a model shop be able to provide a replacement based on a visual inspection. The servo raises and lowers a string loaded arm which contains two magnets for increasing and decreasing the resistance.

Thanks

coolwings

You could have stripped the splines on the inside of the servo arm when it fits onto the shaft coming out through the case , and that produces a similar effect, and a new arm cures it.

More likely a gear is stripped. they can be fixed wiht new gears, but I just replace servos when it (rarely) happens.

Model shops have servos of several sizes and quality. Bring the old one with you for identification.

peter_dublin

Hi Coolwings.

That's what I was hoping to hear, there is a model shop 500m down the road from me so will pop in there later. I'll update you when I know.

Peter

Bruthal

They can be fixed, the damaged gear if its the final gear on the output shaft can be rotated to a different position, and the mechanical stop filed off, as the final gear only rotates 180 degrees or so at most, and usually less.

Not worth the hassle though, but i have done it myself. Servo`s of all sizes are widely available anyway.

Metal gear servos can avoid this, but the plastic gear ones are usually durable enough for most uses.

peter_dublin

Thanks for help everyone, I dismatled what turned out to be a gearbox unit and found that the 22mm 40 to 12 reduction gear is stripped and will need to be replaced.

Hopefully going to examine a few rebuild kits for servos to try and find a matching gear.