The history of mechanical projects dates back to prehistoric times, when early man first made a stone ax by lashing a sharpened stone to a wooden handle. The first steam-powered turbine was invented around 100 A.D. Today, the creation of homemade mechanical projects continues. The technology and tools have changed, but the spirit of inventive curiosity is the same.
Before undertaking project, evaluate your own capabilities. Capability does not necessarily mean ability. You may be able to design a complex machine, but you may not have the tools to make the parts. If so, look to small machine shops and fabrication facilities. A shop can make the part if you have the blueprints in hand. Discuss your needs and arrange labor and materials pricing accordingly.
Your abilities deals with how in-depth your knowledge base is. Advanced tinkerers know how to draw and read blueprints. If you do not, a variety of resources, such as community-college classes or books, can teach you how. Also, you must be proficient with tools and machines, such a file or drill press. Again, shop classes can teach you these abilities. As with all tools, you should also work safely, wearing safety goggles and ear plugs around power tools and other necessary protective clothing.
You may need a certain size bearing or a certain size shaft. Look to salvage equipment to find the needed items. Old printers are usually thrown away, but these devices are full of small, high-precision bearings, shafts, bushings and gears. If you need to purchase parts, consult industrial supply houses.
Many engineers and parts suppliers provide technical data free. These include technical drawings of the parts sold or thermal limits.