DIY Extrusion Screw Grinding Setup | Mechanical Design and 3D-Printing

Making a metalworking process possible with 3D-printed tooling Extrusion screws normally need industrial machining equipment. For this project, I designed a complete grinding fixture that lets you make a 20 mm diameter, 20 mm pitch plastic filament extrusion screw at home. It uses a standard 4" angle grinder, 3D-printed parts and off-the-shelf hardware. The challenge Make a precise screw geometry without a lathe or CNC. The fixture had to hold the workpiece, guide it at the correct pitch, and work with common tools. What I designed Custom 3D-printed components (PETG) that hold and guide the workpiece during grinding An adjustable grinder attachment that fits almost any 4" angle grinder A timing pulley drive (20T to 50T) that sets the screw pitch An M8 to M20 workpiece connector, easy to modify for other screw diameters A linear shaft and bearing guide system built from standard McMaster-Carr parts A fully parametric design that can be adapted to other screw diameters and pitches Specs Build size: 600 x 400 x 200 mm Material: PETG plus off-the-shelf hardware Manufacturing: 3D printing only, no machining of the fixture Build time: about 1 week Deliverables 3D CAD models (STEP) Print-ready files (STL) Engineering drawings and assembly instructions (PDF) Bill of materials with McMaster-Carr part numbers Skills demonstrated Mechanical design, fixture and tooling design, design for 3D printing (DfAM), assembly design, BOM creation, technical drawings, and design for low-cost manufacturing. Need something similar? I can design custom fixtures, jigs, mechanisms and 3D-printable parts for your own project, and adapt this design to a different screw size or pitch. Message me with your requirements and let’s work on it together. 🔗 Full project and free files: https://bazaljunaid.com/extrusion-screw-project/