Q:

To define a custom model name in rails

Can anyone suggest me how I can define a custom model name.  When I tried to generate a model with name 3AForm it's raising a error.  
rails g model 3A_Form date_of_investigation:date date_of_transcription:date by:string                    investigator:string type_of_investigative_activity:text results_of_investigation:text

A:

That's not going to work, 3A_Form is not a valid class name in Ruby.  Perhaps you should try rails g model Form3A ... instead.  If you need to connect your model to an existing table with a strange name then you can use table_name in your class:
class Form3A < ActiveRecord::Base
    self.table_name = 'your_weird_table_name'
    #...
end

