YouTuber builds lathe: 3D printing as formwork for the concrete machine bed

Developer Maxim Kachurovskiy demonstrates how to build a functional lathe using 3D-printed molds and concrete. The goal: a rigid machine bed that safely absorbs the forces and vibrations of metalworking. The printed parts do not serve as a load-bearing structure, but rather as formwork. High-strength concrete is poured into this mold.

This creates solid components with high moment of inertia and good vibration damping – both crucial for precise machine tools. The maker reports that his own design surpasses many hobby lathes in terms of rigidity and functionality. In the videos, the machine demonstrates face turning, longitudinal turning, and thread cutting, including a conical thread flank.

The construction follows a simple process: First, negative molds are created for the bed, bearing blocks, and holders. Then inserts are placed and the cavities are filled with concrete. Metal inserts such as threaded rods or sleeves are embedded during casting so that they can later serve as fastening and adjustment points. This gives the machine defined reference edges for the guide, spindle, and tailstock. It is important to allow for sufficient shrinkage and curing time so that the bed does not warp and the holes fit later.

Epoxy granulate is also used in the DIY CNC scene. However, concrete provides a lot of mass at low cost, provided the mold is correct. Cleanly aligned guides and spindles remain crucial for precision, not the material alone. When printing molds, make sure the surfaces are smooth, use a good release agent, and ensure sufficient wall thickness so that the casting pressure does not burst the formwork.

Safe use requires protective covers, an emergency stop, and reliable chip protection. The construction is complex and time-consuming, but it eliminates the need for special tools because complex geometries come directly from the printer. During operation, high mass, short force flows, and precisely aligned assemblies are important, otherwise the surface quality will suffer. Anyone who wants to replicate this should ideally have experience with concrete, metalworking, and machine safety, because metal cutting requires high feed forces and stable fixings.