Bits and Pieces

Use this category to describe KAPping accoutrement extant and desired. Share with us the little bits that make KAPing life easier.

Attaching micro servo horns to standard gears …

I do not have access to 3-d printed gears. There seems to be no commercial supply of servo gears for micro servo splines. I needed a large servo gear to achieve a proportional pan control on my (yet to be cannibalized) RC transmitter. It is somewhat of a challenge to mount micro servo horns to a purchased gear, keeping the center of the horn at the center of rotation especially when the purchased gear has a 1/2 inch axle hole. I have found a workable alternative to just eye-balling the location and trying to keep the alignment while drilling for screw attachment. I lace the horn onto the gear with kite sewing thread in a symmetrical pattern with multiple laps pulled tight. If it all works out, the lacing centers the horn and the newly mounted gear runs smoothly, and then I can then go back and drill holes for very small screws or soak the thread in CA glue for a more durable attachment.

Shown here are an 80 tooth and a 52 tooth gear with the lacing but no screws as yet. The circular micro servo disk works more efficiently than the cross-arm. I am replacing the 80 tooth gear with the 52 tooth gear on my newly built KAP rig now that I have figured out a way to increase the throw of the micro pan servo. The replacement will result in a lower angular velocity and just a bit more smoothness in the rotation of the rig.


  • Great solution! We often forget, how many things (besides kites of course!) could be sewn together as the most effective way of fixing something. And didn't even the Vikings sew the planks of their ships? ;-)

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