Américo Costa CENFIM – Centro de Formação Profissional da Indústria Metalúrgica e Metalomecânica
Nutcracker 3D printing offers many opportunities in industry, but we cannot forget the home market. Using this technology we can print utensils and items for domestic use, customized and adjusted to our needs. The following case is a nutcracker, Figure 1, where the practical utility is demonstrated for developing domestic items made and customized to our own requirements.
robótica
20
portugal 3d
Digital Manufacturing and Teaching in the area of 3D Printing. Practical Case – 2
Figure 2. Shaft component.
Figure 1. Nutcracker.
In this set made up of three components, we have two types of mechanical connection: A threaded connection, a square thread between the shaft and the ring, and a sliding connection between the handle and the threaded shaft. We will define a clearance of 0.2 mm in the threaded shaft’s connection with the ring, between each cylindrical surface, and 0.25 mm between the sides of the square thread. In the connection with the handle and the threaded shaft, since the connection is tight sliding fit, the nominal dimension for the orifice in the shaft and the diameter of the handle will be the same, 10 mm. The first component to be printed will be the shaft, Figure 2. Using CAD software, we must first model the shaft in 3D and then the ring. When creating the threaded aperture in the ring, we use the shaft to create the thread by subtraction. Before subtracting the volume of the thread from the ring, we must apply and additional thickness all around the shaft to generate the desired clearances.
The shaft’s printing should be carried out with it in a vertical position, Figure 3, and following this, it’s necessary to remove the support material from the grooves in the thread, but this has the benefit of a more perfect finished shape.
Figure 3. Pre-visualization of the shaft’s print.
The next component to be printed is the ring, Figure 4.