4 Point Bend Specimen & Test Fixture

myminifactory

I'm working on a blog series detailing the design of a partially 3D printed test machine and its use in analyzing mechanical properties of 3D printed materials. Check out the project at the link below - all feedback and fresh ideas are greatly appreciated! The rectangle is a custom-designed test specimen tailored for a 4-point bend loading on my machine. This part should require 200 pounds to break when printed at 100% infill. The test fixture design is also included here, intended to reduce the size of later BOMs. The fixture is designed so that the load path is 100% steel-to-steel, avoiding any plastic, which keeps the frame stiff. http://engineerdog.com/2015/03/24/introduction-to-3d-printing-materials-testing-series/