Override Devise password controller, Rails 4

I want to override Password controller to different create action. So I could generate random password and save with user then send that password to user e-mail.

I have like this. routes.rb

   devise_for :users,  :controllers => { :passwords => "passwords" }

Password controller.

 class PasswordsController < Devise::PasswordsController
      def create

                  size = 6
                  charset = %w{ 2 3 4 6 7 9 a v n A j C u D q E i F p G m H J K M N P Q R T V W X Y Z}              
                  self.resource.password = (0...size).map{ charset.to_a[rand(charset.size)] }.join
               if    self.resource.save(:validate => false) 

                self.resource = resource_class.send_reset_password_instructions(resource_params)
             else
              #do nothing yet
              end
      end
    end

This code sends e-mail to user but expected password isn't there.

resset_password_instructions.html.erb

<p>Hello <%= @resource.email %>!</p>

<p>Someone has requested a link to change your password. You can do this through the link below.</p>

<p>Your new password is <%= @resource.password %></p>


<p>Your password won't change until you access the link above and create a new one.</p>

What I am doing wrong?

Thanks in advance.