Our site is under construction and the information will be updated as we continue to test the prototyping machines

CNC Machining Benchman VMC 4000... General Information

Light Machines Website

Note: that our site is under construction and the information will be updated as we continue to test our prototyping machines.

Computer Numerical Control (CNC) Machining

The Computer Numerical Control, CNC, Machining process produces 3D objects by removing material. Automated milling machines are pre-programmed cut away material according to a specific path.

Several cuts are usually necessary; first a rough cut using a large-radius bit (no tight inside corners) and afterwards final cuts to exact dimensions and when the part must be re-oriented due to complex geometry.

The operator on the CNC Milling machine is accurate to within 0.001" and is several times faster than any human. The processes of tool selection and changing, and work piece cooling are all automated and handled by the milling machine.

The advantages of using a CNC mill include

• Variety of materials
• Recyclability
• capacity to produce high-quality metal molds
• Accuracy The CMM (coordinate measuring machine) raises the accuracy of the tool movement (to within ± 0.0004 of an inch)

CNC MILL has uses G and M codes to describe the cutting and spinning motions of the tools as well as their speed.

G codes specify motions while M codes specify machine commands.

G code can be written by hand or generated by proEngineer.

Materials

• Aluminum
• Carbon Steel
• Stainless Steel
• Titanium
• Magnesium
• Plasticized woods
• Brass
• Copper
• Special Alloys
• Plastic
  
  

Limitations

The CNC Milling procedure has the following limitations:

• The CNC mill uses rotary bits, so when milling inside corners, a radius is unavoidable. Outside corners can be made quite sharp if necessary, but some inside corners can have as a minimum the radius of the cutting tool.
• Tool bits wear down and deteriorate with use. This is particularly significant when the material being cut is as strong as the drill bit used (metal cutting metal).
• Enclosed milling machines have a limited interior region.
• The movement of the cutting tool itself is limited; in general it is less than 18" in any direction so the part must be moved if milling is to be performed on more than this range of distances
• the t edious process to generate the G code file.