How Rescale Skeleton before envelope?

[Deviss]

hi there to everybody !!, i dont want give up on vehicles, so i am trying make new ones, and maybe make playable heavy droids as crabdroid, but i have a little problem, how i rescale skeleton before envelope my model ? i tried the same way than rescaling model, but skeleton never take the new scale :S.

Help please thanks in advance

EDIT: i tried set neutral and free all transform but nothing all about boneroot or model envelope but didnt work