Testing wrecked servos
 

I recently crashed a plane and was wondering how to go about making sure the servos are still reliable. The airframe was destroyed (bad enough to shatter spruce spars). I had JR DS811 servos throughout, except for the rudder/tailwheel, which had a DS821.

The servos for the tail section should be fine, as this was a nosefirst attempt to get to China via the shortest route (at least it was moderately soft dirt and not concrete), but the wing servos (4 of them), especially the two inboard servos, seemed to take a pounding. It broke one of the DuBro HD servo arms, and bent up the 4-40 steel rods.

I grabbed a few of the servos and hooked them up. They sound fine, and when I put a load on them, they don't move. I can stop the servo arm completely and the servos just buzz away with no slipping.

Is there anything else I can do to be sure these servos will still operate accurately and safely? Should the potentiometers and the other sensitive electronics still be ok? I don't want to risk another plane due to servo failure, or even worse, risk the chance of hurting myself or another person.

Thanks!

RE: Testing wrecked servos
 

usually it is the gears that strip in a crash or the servo case itself .if the servo's are working then the electronics should be okay.you should be able to remove the top cover to inspect or even replace the gear set.if there is any doubt just send them in for service,the cost will be minimal versus the cost of plane engine and whatever it may hit if something did go wrong.

RE: Testing wrecked servos
 

Hi!
Take the servos apart and have a look if in doubt ! It's very simple and easy to do.
There is always 4 gears in all servos and the gears can only be placed at one place, so you can't do anything wrong.

RE: Testing wrecked servos
 

I'm going to take them apart and visually inspect the gears. :)

Thanks!

RE: Testing wrecked servos
 

After gear inspection sometimes I will mount the servos to the table and lift a weight off the floor. I move the weight through the entire range of servo travel.

Bill

RE: Testing wrecked servos
 

I just grabbed the servo arm and held it still while moving the sticks. The motor whined about it, but no slipping. Not sure how good that is for the servo, but I just did it enough to see if the gears would slip.