Laravel validation request class return model with errors

When validating a form with a request class you can manually validate the data using the validate() method but what do you return back I've tried return $this and return $this->errors but it just shows SQL integrity constraint duplicate entry which is correct but it doesn't show my form with the errors. When doing validation inside the controller you return the model and the errors but what do I return and set errors on validate method in the request class.

Request Class:

namespace App\Http\Requests;

use App\Http\Requests\Request;
use Auth;

class ProductRequest extends Request
{
    /**
     * Determine if the user is authorized to make this request.
     *
     * @return bool
     */
    protected $action;

    public function authorize()
    {
        if(Auth::check()) {
            return true;            
        }        
    }

    public function validate() {

        $v = \Validator::make(parent::all(), $this->rules());
        if ($v->passes()) return true;
        $this->errors = $v->messages();
        // tried returning $this; and $this->errors
        return false;         
    }

    public function all()
    {
        $data = parent::all();

        if( $data['slug'] === '') {
            // if the slug is blank, create one from title data
            $data['slug'] = str_slug( $data['title'], '-' );
        }

        return $data;
    }

    public function messages()
    {
    }

    public function rules() {
    }

}