While I have been waiting for the end-mills, drill bits, 6mm acrylic sheets and acrylic glue to arrive, I have been working on other projects. The orders have arrived and I have finished the other projects.
Where was I?
Here is may last plan for 6 mm thick acrylic:
My last Section:
May last layout for my CNC mill:
The layout shows two slew bearings while the section has three bearings. The prototype bearing was quite good so I don't think I need the second bearing on the tower.
I also have not really considered the tower and the base board.
CNC Mill Parameters
- Restarts: Add origin and maximum extent realignment holes.
- Job Size: One piece at a time.
- Feed Speed: 1200 mm/min (up from 600 mm/min).
- Depth Speed: 150 mm/min.
- Drilling: Peck.
- Over Depth: 0.5 mm (down from 1 mm)
- Spindle RPM: As low at I feel comfortable with, about 3/4 on the dial.
- End Mill: Flat two flute 2mm diameter (better if single flute).
- Cut Depth: 0.25 mm (if all works well this can be increased to 0.5 mm).
- Compensation: 1.8 mm cut width for nominal 2 mm bit diameter (may need to be reduced).
- Use conventional and climb cutting directions where appropriate.
The working envelop needs to be 2:1, the key assumptions are:
- Arm 1 length: 200 mm
- Arm 2 length: 150 mm
- Arm 2 rotation limits 10 to 140 degrees
I calculated the following:
|Dy||173.735||Working Area Height|
|Dx||347.469||Working Area Width|
|L1||200.000||Arm 1 Length|
|L2||150.000||Arm 2 Length|
|A1Min||-6.143||Calculated Motor 1 Range (Min)|
|A1Max||115.600||Calculated Motor 1 Range (Max)|
|A2Min||10.000||Motor 2 Range (Set Min)|
|A2Max||140.000||Motor 2 Range (Set Max)|
|Ox||-173.735||Bottom Left Corner|
|Oy||128.598||Bottom Left Corner|
Here is the base board layout including the tower location:
It fits on a 400 mm x 400 mm board. This layout has a effectively wider feet spacing.
The normal layout is still 400 mm x 400 mm: