undefined method

I am trying to add a page to my exisiting database and for some reason
I get an error of "no method" I searched a lot but my problem did not
get solved, so i'd appreciate if anyone can help me with this:
I am trying to add a page called new_lab which is linked through my
labs page, here is my controller:
#new lab
    def show1
        @hide_sidebar = true
        @patient = Patient.find(params[:id])


   def new_lab
    @hide_sidebar = true
    @patient = params[:id]
    @nlab = @patient.nlabs.build(:patient_id => @patient.id)


  def create_lab
    @hide_sidebar = true
    @nlab = Nlab.new(params[:nlab])
    if @nlab.save
      flash[:notice] = 'Lab was successfully created.'
      redirect_to :action => 'show1'
      render :action => 'new_lab'


I get an error of "undefined method `nlabs'" and I already made a
model and a table by that name. I don't understand what I am doing


@patient = params[:id] should be changed to:
@patient = Patient.find params[:id]

Otherwise it's just a string, and has no method called "nlabs".