Servo motor to impart rotation

[10800]

Hi, I'm looking for a suitable servo that will impart a 90 degree rotation on a vertical rod (from a French mechanical signal that rotates from face-on to side-on).

 

What can you recommend from your own experience please?

 

Thanks.

[Nigelcliffe]

Put servo directly below rod.  Make a small coupling to fit in end of servo to join to rod.  Job done.   
If you're lacking tools to make such a coupling, the quick way is to take two servo "horns" (the arms which come with them) of the same shape/size - works slightly better with a two-arm types.  Fit one to the servo.  Fit the other, upside-down, to your signal shaft (glue it on if no other method available!).  Join the two horns together at their drive pin holes - bit of twisted wire will work if you've nothing else ! 

 

Most servo controllers offer at least 90 degrees of movement, some more.  

 

( I was involved in adding such a mechanism to a layout for Glasgow show, about a fortnight ago - that had a signal with a 90 degree movement of the signal head, shaft down through layout.   We used a MERG Servo-4 board to drive it, but any servo driver board should do the job.  ).

 

 

- Nigel

[10800]

Thanks Nigel. This will be a first-time use for servos in my case, so I'm learning! I take it Tower Pro SG90s would do the job? This isn't a DCC layout, does that matter if I use the MERG Servo-4?

 

 

 

 

[Grovenor]

The SG90 is fine for the job.

The MERG Servo4 is not a DCC item, it will operate just with switches/relays, or from other electronic logic. It provides drivers for 4 servos, MERG also has drivers suitable for a single servo which are more suitable if you don't need 4.

Rgds

[10800]

Thanks Keith 

 

Looks like a Servo4 and a single will do fine. I (will) have two signals on one layout board, each of which has two rotating boards, and one on another board which has one rotating board. The doubles are like this, where the square chequered board (a carré, like a stop signal), and the yellow diamond (like a distant), rotate to be edge-on to the driver when in the off position.

 

 

Cheers

 

 

 

 

 

 

[Andy Reichert]

I have a feeling that, given the likely tiny torque needed, a common vibrator motor and a current limiting resistor as a stall motor would be a very inexpensive and miniature solution.

 

Andy