RhinoCam: CNC Machining Simulation

RhinoCam is a plug-in for Rhino 5.0 that simulates CNC milling. An illustrator, PDF or Rhino file of a particular object to be cut by the mill is input into the program, and the output is the final, digitally cut result. These objects can be physically milled from plastics, wood, and metals. The settings of the mill can also be adjusted, potentially to the specifications of the physical mill and mill tools that one has on hand. This is useful for digtial fabrication- essentially, it simulates what your CNC mill is going to cut prior to making the actual physical cuts. To download the 90-day trial of the RhinoCam plug-in, visit http://mecsoft.com/rhinocam-software/.

Instructions:1. Type ‘Import’ into the command bar to bring in an external file. (AI. or PDF. file)2. Preserve units in 1:1 ratio.3. Under program tab and double click on ‘Stock.’ This is any material you would like to carve with the CNC mill.

4. In the ‘Box Stock’ dialog box, click on upper left hand radial button to zero material in the upper left hand corner.

5. Zero the coordinates under the ‘Corner Coordinates’ option. (Xc = 0, Yc = 0, Zc = 0)

6. Add in overall dimensions of the stock. (i.e. L = 12, W = 12, H = 1) Stock is your material. Steps 4-6 centre your graphic template in the middle of the stock.

7. Go to ‘RhinoCam’ tab and select ‘mill’.

8. Select ‘Machining Browser’ icon to bring up ‘Machining Browser’ dialog box.

9. Select ‘Regions’ tab.

10. Click on ‘Create Machining Regions Set’ icon.

11. Rename ‘Machining Regions Set’ to desired name (i.e. object)

12. Deselect graphic and click on ‘Select Curves’ icon to create a subset of the region set. In viewport select interior curve and rename the subset ‘Interior’ in the dialog box.

13. Repeat the above step for the exterior curve and name subset ‘Exterior’ in the dialog box.

7

4

5

6

8 9

101311

12

14. In ‘Machining Objects’ dialog box select the ‘Tools’ tab and click on the ‘Create/Edit Tools’ icon.

15. In the ‘Create/Select Tool’ dialog box, select the profile of the mill. This varies depending on the settings of your mill, but the most commonly used profile is that of the flat mill (second icon from the left).

16. Select tool specifications. Again, this will vary based on the mill one wants to model, but common settings are: tool diameter = 0.5, flute length = 2 and material is carbide.

17. Rename the tool 1/2 edge flat.

14

15

16

17

18. In ‘Machining Brower’ dialog box, select the ‘Program’ tab and under ‘Machining Operations’ click on ‘2-Axis’ and select ‘Profiling’.

19. In the ‘21/2- Axis Profiling’ dialog box, select ‘Machining Features/Regions’ tab. Click on the ‘Select Pre-Defined’ button. Click on ‘Interior’ and then ‘OK’. This is done because the interior requires one cut path and the exterior requires another cut path, so a total of two cut paths are required for the example object.

20. Under the ‘Tool’ tab, simply select the named tool.

18

19

20

21. Under the ‘Feeds & Speeds’ tab, you want to change the way the tool moves in the X and Y axis. Although this differs based on preference, a common cut rate would be 100 in/min. So change ‘Cut(Cf)’ = 100 in/min

22. The ‘Clearance Plane’ tab measures how high above the table the tool lifts as it moves across the cutting surface. This is useful if you have clamps sticking out of the surface that you want to model and incoprate into the simulation but otherwise it does not to be modified.

23. Under the ‘Cut Parameters’ tab, check the box for ‘Use Outside/Inside for Closed Curves’ and select ‘Inside’ because we will start with interior first.

21

22

23

24. Under the ‘Cut Levels’ tab, depth of cut is set. It’s best to set the ‘Total Depth of Cut’ option at a height slightly greater than the material thickness to account for issues such as material warping. As such, for a 1 inch thick piece of material, ‘Total Depth of Cut’ should be set at 1.1 inches.

25. For the ‘Rough Depth’ and ‘Fine Depth’ options, the ‘Rough Depth’ is generally only used. This should be set at the same height as the ‘Total Cut Depth’ - 1.1 inches.

24

28

25

26

27

26. Because the cutting segment of the tool is 0.25 inches, ‘Rough Depth/Cut’ must be set to 0.25. Again, ‘Finish Depth/Cut’ is 0.

27. ‘Depth first’ should be selected, rather than ‘Level First,’ so that the bit moves up and down first rather than back and forth; this creates a cleaner, quicker cut.

28. Under the ‘Entry/Exit’ tab, the way the bit approaches the stock is set. This is not necessary to change but is depedent on the mill you are modelling.

31. Under ‘Sorting’ tab select ‘No Sort’ because we do not have multiple objects to select.

32. The click on ‘Generate’ button. This will generate the interior cut.

29

30

31

32

29. The ‘Advanced Cut Parameters’ tab will create bridges in order to keep the stock from flying of the table.

30. Under the ‘Bridges Tab’, select the ‘Create Bridges’ checkbox. Change the number of bridges to 3 or 4. When we made our bridges an inch long under the ‘Height and length’ tab, the mill did not correctly cut the object because the bridges were in the way. Therefore, smaller bridges were required.

33. Now we need to do the exterior cut. Because it is almost identical to the interior cut, we can copy and paste the parameters of the interior and then make slight adjustments to make it exterior. Firstly, under ‘Setup 1,’ highlight the first folder, then copy and paste it.

34. Re-label the first folder ‘interior,’ and the second copied folder ‘exterior.’

35. Double click on the ‘exterior’ folder; a few adjustments have to be made, but not many. The region to be cut must be redefined as ‘exterior’ rather than ‘interior’ in the ‘Machining Features/Regions’ tab (refer to step 19). In the ‘Cut Parameters’ tab, cut location should also be altered to ‘outside’ instead of ‘inside’ (refer to step 23).

36. Then click ‘Generate’. This will generate the exterior cut.

37. In Maching Browser, under Setup 1 folder, right click on ‘Interior’ and click ‘Simulate’. Repeat with ‘Exterior’ folder.

3433

37