Week 07
Week 7 - Computer Controlled Machining
This week we learned and practiced Computer Controlled Machining on a CNC matchine (Computer Numerical Control).
Group assignment:
- Complete your lab's safety training
- Test runout, alignment, fixturing, speeds, feeds, materials and toolpaths for your machine
- Document your work to the group work page and reflect on your individual page what you learned
Computer Controlled Machining Process¶
- Measure material
- Design something BIG
- CAM -> Gcode generation
- Gcode is checked by someone
- Design milled
- Design assembled
- Design finished
1. Measure
2. Design
Using a 3D design software prpare a model with parts that you would like to cut on CNC. This tutorial provides a great guide for how to go about creating a design that will work well on a CNC matchine
3. RinoCAM
A good tutorial for RinoCAM can be found here
Steps for setting up your cuts in RinoCAM
1.Select Machine - 3 axis CNC_STEP_BCN
2.Box Stock:
Stock Geometry: origin in the top left buttom corner
Corner coordinates: 0, 0, 0
Dimensions: L, W, H
3.Screw material and then around the area you want to cut
4.Draw points in Rhino where you have located your screws
5.Go to Machining operations - 2 axis
Roughing
Pocketing (emptying part of the material)
Engraving (on cut) (choose it for making the "screws" spot and then select the points where you want to make the mark)
6.Create/Select Tool
7.Fablab just have bold and flat mills.
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For the screws choose flat (next parameters should be according to the one you are going to use)
-
Name it (this is an example of mill bit values, you have to choose your own)
- Holder Dia: 30
- Holder Len: 45
- Shank Dia: 6
- Tool Len: 105
- Shoulder Len: 60
- Flute Len: 45
- Tool Dia: 6
- Flute: 1
- Spindle Parameters:
- Speed: 18000 RPM,
- Direction: CW,
- Cut (calculate with cheapload equation): 4500,
- Retract: same as Cut,
- Departure: same as Cut.
- Plunge ("half of cut"): 2000,
- Approach: same as plunge and Engage: same as plunge.
- Clearance Plane: Clearance Plane Definition: Part Max Z + Dist: 20 (Never Automatic)
- Cut Parameters: we only care about "Cut Depth Control": 3mm
- Entry/Exit:
- Sorting: Minimum Distance Sort
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For pocketing:
- Feeds and Speeds: 18000 RPM
- Clearance Plane: Clearance Plane Definition: Part Max Z + Dist: 20 (Never Automatic)
- Global Parameters: Climb
- Cut Patter: Offset
- Do everything else!!!!!
For profiling/outside: use along path! when using profiling the machine doesn't recognize other pieces. So we'd like to use along path so it can slide and approach directly to the selected piece. Remember to add taps (bridges).