If you have a general idea of what you want to make, these factories will help refine your idea and think through the different components that involve the making of your idea.
A pattern-maker is someone who makes a blueprint of your idea. They make sure your design will be well-constructed.
"Production run" means making a lot of one product at once. The factories listed under "production" can produce small and/or large quantities. The minimum order for a production run can vary from factory to factory (some have no minimum, some require a dozen, and some require up to 1,000 to be made at once)