For ambitious makers, buying a 3D printer doesn&#039;t offer nearly enough challenge or control. For those makers, there are a growing array of component makers, including B3 Innovations, whose Pico &quot;hot end&quot; offers greater performance, flexibility, and reliability than other print heads. It&#039;s intended for use in 3D printers made according to the open-source RepRap specification. Here it is in action, printing an object in a RepRap printer.