• Developed by Scott Crump, and Stratasys has been selling the machine since 1991.
• The concept is that material is heated and then in controlled quantities deposited directly on previous layers. Eventually layers are built up to complete the entire part.
• The materials are available on spools of 1/2 mile in length, at costs from $175(US) to $260(US). The filaments are 0.05”
• As usual the .STL file is sliced into layers, and the slices are used to drive the machine.
• The key to this method is an extrusion head,
- the material is fed into the head
- the material is heated until melting
- the material is then extruded from the tip in controlled quantities
- the material is wiped on the previous layer
• The extrusion head is moved about the table with an x-y positioning system to deposit material on each layer
• The platform the part is on drops when a layer is complete to allow the addition of a new layer.
• slice thickness is 0.002” to 0.03”
• material changeover requires a few minutes of “flushing-out’
- a good variety of materials available
- tolerance of +/- 0.005” overall
- the extrusion head must continue moving, or else material bumps up
- part strength is weak perpendicular to build axis.
- more area in slices requires longer build times
- temperature fluctuations during production could lead to delamination
• selected specifications for the FDM1000 are,
