Gantry CNC
Summary
This system can cut 2d and 3d shapes from materials such as wood, plastic, metal and composites. It is useful for cutting things that can't be cut in the laser cutter due to their thickness or material compatibility. The edge accuracy of parts is also usually better than a laser cut due to the lack of uncertainty about the kerf width, and improved vertical walls.
We made this CNC from the UCL donated linear slides and stages, and other things lying around the space, and some bits and pieces that members had. Any suggestions for improvements / modification are welcome.
Specs
- Spindle 1750 to 17500rpm
- Rapid traverse rate at 100% 2000mm/min
- Axis travel
- X(cross) 850mm
- Y(longitudinal) 960mm
- Z(vertical) 80mm (Phase 1), 200mm (Phase 2)
Technical
The system currently runs LinuxCNC on the PC built into the base.
Using the system
- The spindle is currently fitted with an ER20 collet chuck and can take cutters up to 13mm diameter. Collets can be found on top of the Boxford CNC.
- To start the spindle, press the green button on the VFD. Use the up and down keys to vary the speed.
Generating g-code from your designs
There are a lot of different options for preparing a g-code file which can be loaded onto the CNC to cut a design. Some examples include;
2D Packages
- MakerCam (Free, runs in a browser via Flash) http://www.makercam.com/makercam.swf
- Cambam (LHS has a license, installed on the Robotics laptop) http://www.cambam.info/
3D Packages
- Autodesk Fusion 360 (Free for hobbyists and students, Windows / OSX) http://www.autodesk.co.uk/products/fusion-360/overview
When using Fusion 360, in order to post to the Hackspace CNC machines, the "Generic EMC2" post-processor should be selected when finally saving the g-code file. LinuxCNC recognises the "ngc" file extension although any extension can be used.
System status
The system is currently able to cut designs, but a vaccuum has to be hand held to capture dust and clean up chips. the main thing currently needed for the system is extraction to avoid putting too much additional dust into the air of the downstairs workshop.