Desktop Lathe

Spring 2014

Role: Mechanical Engineer

Team: 7 Students (Mechanical Engineering)

Skills: Rapid Prototyping, CAD, Design for Manufacturing

Tools: Machine Shop, Waterjet, Solidworks

My team built a desktop lathe designed to machine aluminum with 50 micron repeatability, survive a fall from desktop height, and continue to machine to a +/- 50 micron accuracy after a sledgehammer blow to the spindle. My main focus was the design of a flexure to define the movement of the tool carriage.  I manufactured multiple parts of the lathe using the CNC mill, waterjet, and general machine shop tools in the MIT Laboratory for Manufacturing and Productivity.

Carriage Flexure Functional Requirements

1. Have a stiffness within specified range

7. Stiffness and support to withstand drop test.

Flexure Loads and Deflections

  • error in rails

  • Lower bound for thickness in vertical flexure - displacement in terms of (Fr) is less than 5 micron

  • Upper bound - avoid yielding due to displacement of rails

Add supporting.guard material on side of flexure

Advantage: protects flexure against impact

Issue: mounting to carriage, less flexible

Solution: Cutouts?

Added fillets at base