RE: Post all your
JR DS3517 actually came out with plastic gear version as Joe mentioned above.
Later, Metal gear versions came out, but DS3517 standard got discontinued.
Reason was the heli guys kept on breaking the gears on 3517.
I have a few of those at home too. Was going to use them on Kyosho Flip, but decided to go with metal gears instead. For use on elevators of Pattern plane should be good.