Servo choice question

[David perry 1]

Im building my DB Autogyro and Ive reached the stage where I have to fit the control pushrods. Pushrods seem rather old fashioned now, and whilst I could fit them Im rather coming down on the side of locally fitted servos in the tail to drive the elevator and rudder.

Quick question: will the small 9g servos do the job do you think? Ive never flown a gyro so not sure of speeds and control forces.

Thanks in advance

David

[Frank Skilbeck]

I used the regular Futaba 3003/148s in mine (with pushrods), these aren't very powerful servos, so a modern 9g servo should be fine, aim for around 3 kg.cm torque.

[MattyB]

3kg/cm is a lot to expect from a 9g servo, you are going to be paying premium prices for a quality digital such as a MKS 6100 if you want something with those specs. Given the generally low speeds of an autogyro and the fact the sticks don't tend to spend their time in the corners I would have thought any decent analogue micro like an HS85 or similar should do the job.

This calculator might help, but should only be considered a rough guide to get you in the ballpark...

Edited By MattyB on 28/01/2016 17:41:11

[David perry 1]

Thanks guys. I had considered 148s but thought the smaller ones would weigh less. Youve rather confirmed what I thought though, so thanks...9gs it will be. Mind you, it's an expensive half ounce weight saving! Tight fisted modeller!!

David