MTM-LJ (“Little John”) - a Big Rapid Prototyping Machine


Final Project - How to Make Almost Anything (MAS863.09)
Natan Linder in collaboration with Laurel S. Pardue

MTM-LJ (“Little John”) is a mid-size multipurpose rapid prototyping machine. The design for this machines is influenced by Jonathan Ward’s MTM-AZ, however in the process of scaling up the machine it was completely redesigned from scratch.

Specifications / Key Features:

    Dimensions: 2’x2’x14.5”

    Working envelope: 9”x18”x5.5”

    Interchangeable tool interface, multiple heads

    I0 Networked motor control (unipolar+bipolar support)

Take a look in the galleries above for pictures describing the different steps required to put a machine together. More updates & tutorial will follow as my time permits.




All the MTM-LJ parts are currently using two 4’ x 4’ x 1” sheets. Parts layout is using spacing for cutting with a 0.25” straight end-mill. Pilot holes should be cut first using a 0.125” straight end-mill, see Fabrication section for detailed screenshots. To make tool-path generation the DXF & Rhino files below are using layers.

Sheet I                                                                  Sheet II

Download plans in various formats:

Tool Interface:

MTM-LJ has an interchangeable tool interface. This design includes an example interface to Ilan Moyer’s DIY Spindle. We are in the process of creating a Plastruder tool interface and a simple camera based scanner interface.  

Old design webpage (on MAS863.09):

Make your own!
(c) Massachusetts Institute of Technology 2009 Permission granted for experimental and personal use. License for commercial sale available from MIT.


So many people! --- J. Ward, D. Carr, Max L., Ilan M. Kenny C. Steffen R., Tom L., John D., Neil G. and the entire class crew of MAS863.09


linder (at) media (dot) mit (dot) edu