Humanities › History & Culture Making a Prototype Share Flipboard Email Print (Ben Hupfer/Corbis/VCG/Getty Images) History & Culture Inventions Patents & Trademarks Famous Inventions Famous Inventors Invention Timelines Computers & The Internet American History African American History African History Ancient History and Culture Asian History European History Genealogy Latin American History Medieval & Renaissance History Military History The 20th Century Women's History View More By Mary Bellis Inventions Expert Mary Bellis covered inventions and inventors for ThoughtCo for 18 years. She is known for her independent films and documentaries, including one about Alexander Graham Bell. our editorial process Mary Bellis Updated May 20, 2019 Before 1880, every inventor had to present a working model or prototype of his or her invention to the patent office as part of the patent application. You do not have to submit a prototype anymore, however, prototypes are great for several reasons. Legally a prototype proves what is called a "reduction to practice". The United States used to hold the first to invent rule, granting a patent to the first inventor who conceives and reduces the technology or invention to practice, for example, a working prototype or a well-written description. Today the United States follows the first to patent rule. However, a prototype is invaluable for business dealings if your invention is still at that stage of funding. Do not underestimate the power of having one.You can include photos of your prototype in your inventor's log book.A prototype helps you figure out any design flaws your invention has and if it really works.It can help you make sure your invention is the right size, shape, and form.A prototype helps you sell or license an invention. You can use it during demonstrations.Making one can prepare you to write your patent application and make your patent drawings. How to Make a Prototype Some of the steps listed below apply in different ways to different types of inventions, for example, a simple wooden toy vs a complex electronic device. Use your common sense to apply the steps in ways that make sense to your individual case. Make a drawing(s) of your invention. If available use the descriptions or drawing from your inventor's log book. Keep all the sketches in your logbook.If you know how you might want to make a CAD drawing of your invention. Simple CAD (computer-aided design) programs exist that you might be able to use yourself.Make a non-working model of your invention out of foam, wood, metal, paper, cardboard. This will test your invention's size and form.Make or plan how to make a working model of your invention. Depending on your invention, you might be casting in metal or plastic. Write down all the materials, supplies and tools you may need and identify the steps needed to assemble your prototype. You might need simple to complex engineering drawings for any electronics. At this stage, you might want to pick up a book or kit on prototyping. You might need to contact professional for quotes on what any work you need to be done will cost.You have to figure out how much a working prototype will cost to make. Remember one copy might be very expensive to make. Mass production brings down the cost per unit. If you can make your own prototype and you can afford it, do it.Do your research on the latest methods and alternatives. For example, plastic injection molds are expensive, however, a method of CAD called "Rapid Prototyping" is an alternative.Depending on your invention, your prototype might be very expensive to make. If that is the case you might want to produce a virtual prototype. Today, computer programs can simulate an invention in 3D and can test that an invention does work. Virtual prototypes can be made by a professional and they cost a thousand or more. They can make you a video or CD animation of your invention working.You may have to create a real working model of your invention if perhaps a buyer or licensee demands one.You may have to hire a professional prototyper, engineer or designer at some point in this process. Our Prototyping Resources includes directories of professionals. Before Hiring a Prototype Maker Discuss your project thoroughly. Make sure that you can communicate well to this person.In advance, agree on fees for the entire project. Prototype makers can charge very high fees by the hour.Tell them exactly what you want to include with as many details as possible. Include your drawings and possibly your virtual prototype files.Make sure anyone you talk to signs a nondisclosure agreement with you before you publicly disclose your invention.