Ailerons & brakes - servo torque

[StephenB]

For servos buried in the wings what would be the recommended torque rating for actuating brakes and ailerons on approx. 4M scale glider under 5kgs?

I have some micro metal geared servos I could use from stock but they are rated under a Kg so may well be too weak?

[Peter Balcombe]

Stephen,
I have used MG90 type servos (1.8Kg/cm) in all of my 1/4 scale models for aileron/brake operation without problems, although I use higher power ones for the flaps.
I’m sure others will use even higher power units, but I would certainly have though 1Kg/cm types would be pushing it a bit.
Peter

[StephenB]

Thanks for the prompt reply Peter, I thought I would be pushing it!

I think I will err well on the side of caution and go for much higher torque rating rather than "just enough". These Turnigy servos from HK look to be ideal: https://hobbyking.com/en_us/turnigytm-b ... 17-4g.html

[Peter Balcombe]

Stephen, they certainly look to be more than man enough as long as they fit in the available wing depth etc.
Note that Hobbyking also do some useful thin wing servos such as the KS PDI-2105MG or PDI-HV2107MG.