Week 07

Computer-Controlled Machining

The seventh lecture on Wednesday March the 8th was about Computer-Controlled Machining: howto make BIG things, like furniture pieces, through the use of a medium-big scale CNC mill. Assignment given by Neil for this seventh week simply was:

  • Make something BIG

Making a Plant Stand

For this week assignment I though about making a simple three-joints Plant Stand in laminated fir wood. I started out frome the design, using Inkscape software. I designed the pieces in the exact layout to be milled; this is the first piece

and this is the second drawing, with the cross on the top

Second, I imported the design, I made the CNC route using ArtCAM software, a very good CAM application for CNC rooting by Delcam, a company now acquired by AutoDESK. I was not super happy with it, since this is proprietary software only available over a Windows system and, as far as I can, I prefer using Free Software -however it worked like a charm! :)

inside ArtCAM sofware interface, it is possible to define a lot of parameters, as endmill; in this case a 3.175mm bit is selected

this is the result route,

here in a 3Dview

Time to start with machining! Beside the fact that a CNC machine can seem very friendly, it'very is important to keep in mind all the times that a CNC mill machine can create severe injuries and even kill people, so it's important to remind basic safety rules:

  • wear a coverall, safety glasses and mask, keep away dust with vacuum cleaner
  • make the work together with a friend that can help in case of emergency ("buddy system")
  • fasten long hair (if any) to make sure cannot reach any part in movement

  • The lamined wood panel is first attached with screws to the MDF sacrificial layer (see blue circle); for this purpose it's possibile to use also clamps, as far as the material to be milled is flat enough.

    Solei CNC machine available at the lab is controlled by MACH3 software application; where is always visibile GCODE

    axis position

    job display

    tool information

    feed rate

    spindle speed

    Time to begin milling of the first piece

    Here G-Code is running

    and axis are moving; each pass, Z is going down and down

    almost finished...

    done!

    Here's the second piece

    and here's the final one

    Putting everything together; it can stand up without any kind of glue or screws, just like as a press fit kit!

    Detail

    and "Hero Shot" with final result; Plant says: "Thank you"

    • Source files