Roland 3-Axis Set-Up

The City University of New YorkArchitectural Technology Dept.

Roland MDX-540Basic 3-Axis Set-Up:3-Axis Positional Milling Strategywritten by Cody Pfleging and Anner More

2

This material is based upon work supported by the National Science Foundation under Grant Numbers 1141234.

Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.

3Roland- 3 Axis Fig. 3 - Machining Objects Menu

Fig. 1 - RhinoCAM Menu

IntroductionRhinoCAM is a plug-in for Rhino used to create toolpaths for the CNC mill. It works from the modeling environment in Rhino to create simulations of the overall milling process before actually performing any milling. It then creates NC files (G-Code) which then can be read by the Roland MDX-540 for the milling process.

Open RhinoCAM Operations Browser: (Fig. 2)

- Toolbar Menu - RhinoCAM - Machining Operations Browser

This is where you set up different machining operations and toolpaths.

Open RhinoCAM Objects Browser: (Fig. 3)

- Toolbar Menu - RhinoCAM - Machining Objects Browser

This is where you load different tools for different machining jobs and regions/boundaries.

Fig. 2 - Machining Operations Menu

Roland- 3 Axis 4

Fig. 6 - Post Processor SetupFig. 5 - Machine Type Setup

Fig. 4 - Machine and Post Processor Icons

Step One: Machine SetupSet up the type of machine and the post processor that will be used for the milling process. In this guide, we will be using the Roland 3-Axis machine and the .nc output file.

Machine Type: (Fig. 5)

- Machining Operations Browser - Machine

Set the Number of Axes to 3 Axis (Fig. 5).

Post Processor: (Fig. 6)

- Machining Operations Browser - Post

Set the Current Post Processor to Roland MDX 540 by selecting it from the drop down menu (Fig. 6). If the post processor is not available, download the post processor (NYCCT_Roland_MDX-540.spm) from NYCCTfab.com by clicking the Fabrication tab and selecting CNCmachining.

Make sure the Posted File Extension is set to .NC by selecting it from the drop down menu if it is not already set (Fig. 6).

Roland- 3 Axis 5

Step Two:Load Endmills

Load Tool Library: (Fig. 7)

- Machining Objects Browser - Load Tool Library

The Roland tool library can be found on NYCCTfab.com by clicking the Fabrication tab and selecting CNCmachining. At the bottom of the page you will find all the necessary support files. Locate and download the tool library (Basic_Roland_Tool_Set.csv).

Fig. 7 - Machining Objects Menu

Roland- 3 Axis 6

Step Three: Pallete and Physical StockWhat kind of stock can the Roland 3-Axis mill?

In order to use the CNC mill a pallete, spoil board and piece of stock must be used.

Standard NYCCT 3-Axis Milling Configuration: (Fig. 8)

The stock (2” HDU) is mounted onto the spoil board (3/4” MDF) using a spray adhesive, making a 2.75”H x 16”W x 16”L assembly. This material that will be milled to produce the desired geometry.

The pallete is the object that the spoil board and stock assembly are mounted on top of. The palette has a grid of holes used to drill screws up and into the spoil board above. Once the spoil board and stock are safely mounted, the palette is fastened directly to the bed of the Roland MDX 540.

NOTE: Screws must be placed in grid locations that will not be hit by the endmill. Both the height of the screw and its location on the grid must be taken into considertation. A minimum of four screws must be used.

Fig. 8 - Screwing Stock to Pallete

Roland- 3 Axis 7

Fig. 9 - Stock Selection

Step Four: Box Stock SetupSetting up your digital stock to match your physical material dimensions.

Create a Box Stock: (Fig. 9)

- Machining Operations Browser - Stock - Box Stock

Set the location of the origin of the stock by clicking one of the corner buttons and set the dimensions of the Stock by typing in its Length, Width, and Height into the text boxes (Fig. 10).

NOTE: This setting corresponds to the orientation of the milling process and must be the same origin at the mill.

Fig. 10 - Stock Edit Fig. 11 - Stock in Model Space

Roland- 3 Axis 8

Fig. 12 - Toolpath Selection: Horizontal Roughing

Fig. 13 - Horizontal Roughing: Machining Features/Regions

Step Five:Roughing ToolpathSpecifying and controlling your toolpath settings.

Horizontal Roughing: (Fig. 12)

- Machine Operations Browser - 3 Axis Adv - Horizontal Roughing

Once the toolpath type is selected a window will open with multiple tabs. These tabs are where the the mill settings are controlled.

Machining Features/Regions: (Fig, 13)

This tab is where you define the area to be milled. To define that area create a curve around the boundary of that area, select that curve and then click the Select Drive/Containment Regions (Fig.13) button.

Roland- 3 Axis 9

Step Five (continued):Roughing ToolpathSpecifying and controlling your toolpath settings.

Tool: (Fig. 14)

In this tab the desired tool is selected. Typically, a flat end mill with a relatively large diameter is best suited for a roughing toolpath.

Speeds & Feeds: (Fig. 15)

This tab is where the movement of the endmill is controlled; speed (RPM) and feed rate (in/min). These setting vary depending on the material being milled. The values listed in the image on the left are best suited for HDU.

Fig. 14 - Horizontal Roughing: Tool Fig. 15 - Horizontal Roughing: Feeds & Speeds

Roland- 3 Axis 10

Step Five (continued):Roughing ToolpathSpecifying and controlling your toolpath settings.

Clearance Plane: (Fig. 16)

This tab defines the height at which the endmill must pick up in order to move from one portion of a toolpath to another. Select Stock Max Z + Dist and specify 0.5 inches.

Cut Parameters: (Fig. 17)

Select outside for the Pocket Start Point in the Offset section. Specify 75 for % Tool Diameter in the Stepover Control section. Since we are mainly concerned with removing excess material during the roughing toolpath, a relatively large stepover of 75% will lower the time required to complete the toolpath without impacting the final finish.

Fig. 16 - Horizontal Roughing: Clearance Plane Fig. 17 - Horizontal Roughing: Cut Parameters

Roland- 3 Axis 11

Step Five (continued):Roughing ToolpathSpecifying and controlling your toolpath settings.

Cut Levels: (Fig. 18)This tab controls the endmill moves downward (negatively in the Z-Axis).

- Stepdown Control: here the parameter by which the endmill moves downward is chosen and the increment is specified. Select % Tool Diameter and enter 75.- Cut Levels Ordering: the mill can either all the cutting of one level of depth first and then move onto the next level or it can go to the full depth of each area and then move to the subsequent areas.

Engage/Retract: (Fig. 19)

This tab defines the way in which the endmill moves in order to engage the material. Select Path and enter 10 for Angle, 0.5 for Height.

Advanced Cut Parameters:

Do not adjust settings in this tab.

NOTE: Run a simulation and check to see that the tool holder (collet nut) is not colliding with the stock.

Fig. 18 - Horizontal Roughing: Cut Levels Fig. 19 - Horizontal Roughing: Engage/Retract

Roland- 3 Axis 12

Fig. 20 - Toolpath Selection: Parallel Finishing

Step Six:Finishing ToolpathSpecifying and controlling your toolpath settings.

Parallel Finishing: (Fig. 20)

- Machine Operations Browser - 3 Axis - Parallel Finishing

Most of the parameters for the parallel finishing toolpath funstion identically to the horizontal roughing toolpath and, therefore, the settings can be repated. This is not true for the Cut Parameters tab.

Cut Parameters: (Fig. 21)

The Stepover Control should be set between 10 - 25 % of Tool Diameter. The exact value here will depend on the desired finish; the smaller the stepover, the smoother the finish.

NOTE: Run a simulation and check to see that the tool holder (collet nut) is not colliding with the stock.

Fig. 21 - Parallel Finishing: Cut Parameters

Roland- 3 Axis 13

Step Seven:Valley Remachining ToolpathSpecifying and controlling your toolpath settings.

Valley Remachining:

- Machine Operations Browser - 3 Axis - Valley Machining

This toolpath will be helpful in removing material from areas that the parallel finiishing pass could not reach.

Machining Features/Regions: (Fig, 25)

Create a region that defines the area needing additional machinging and select that region for this parameter.

Fig. 22 - Valley Remachining: Perspective View Fig. 23 - Valley Remachining: Top View

Fig. 24 - Toolpath Selection: Valley Remachining Fig. 25 - Valley Remachining: Regions

Roland- 3 Axis 14

Step Seven: (continued)Valley Remachining ToolpathSpecifying and controlling your toolpath settings.

Cut Control: (Fig, 26)

A surface is machined if the angle of its normal falls within a range specified here in this parameter. Enter the values found in the highlighted area.

Cutting Parameters: (Fig, 27)

Stepover Control should be a maximum of 25 % of Tool Diameter.

NOTE: Run a simulation and check to see that the tool holder (collet nut) is not colliding with the stock.

Fig. 26 - Valley Remachining: Cut Control Fig. 27 - Valley Remachining: Cut Parameters

Roland- 3 Axis 15

Step Eight:Horizontal Finishing ToolpathSpecifying and controlling your toolpath settings.

Horizontal Finishing: (Fig. 28)

- Machine Operations Browser - 3 Axis - Horizontal Finishing

Maching Features/Regions: (Fig. 28)

For this parameter we will need to make two different regions. The frist will be offset from the border of your geometry by the radius of the tool selected for this toolpath. Fillet the corners of that region by the tool’s radius. The second region will be offset from the first region by the diameter of the selected tool plus 0.05” for machine tolerence.

Fig. 28 - Toolpath Selection: Horizontal Finishing

Fig. 29 - Horizontal Finishing: Regions Fig. 30 - Horizontal Finishing: Top View

Roland- 3 Axis 16

Step Eight:Horizontal Finishing ToolpathSpecifying and controlling your toolpath settings.

Cut Parameters: (Fig. 31)

Select Conventional in the Cut Direction section of this parameter.

Cut Levels: (Fig. 32)

Use settings shown in image for this parameter.When specificying the height of Bottom in the Cut Levels section be aware of the relationship between the overhang of your endmill and the depth controlled by this value.If your material is 3” in depth and you specify that the bottom cut level can go no lower than 0.25” from Z zero, than, the tool can go a total depth of 2.75”. Therefore, the minimum overhang of your endmill for those settings equals 2.75”. There is a potential for collision if these considerations are not made for this parameter.

Entry Exit: (Fig. 33)

Select Along Path 3D Entry.

Fig. 31 - Horizontal Finishing: Cut Parameters

Fig. 32 - Horizontal Finishing: Cut Levels Fig. 33 - Horizontal Finishing: Entry/Exit

Roland- 3 Axis 17

Fig. 34 - Simulate Tab

Fig. 35 - Simulation Model

Step Nine:Simulate ToolpathsConfirm that toolpaths are safely producing the intended results.

Run Simulations: (Fig. 34)

- Select the toolpath to simulate - Machine Operation Browser - Simulate - Play

Detect Collisions: (Fig. 35)

Running a simulation of each of your toolpaths prior to posting is an essential part of the CNC milling process. It is very difficult for even an experienced RhinoCAM user to be confident that based on the data entered in your toolpathing parameters you will produce the model you intend without first running the simulations. The most important reason to run the simulation of your toolpaths is to detect potential collisions.

In this image the collet has collided with the stock. The areas where the collision has occurred are shown in red. This type of collision typically occurs when a endmill with a relatively small diameter is used (1/8” or less). These smaller endmills typically have shorter tool lengths, as well. As a result of this shorter tool length, the collet must move deeper into the stock in order for the endmill to reach its cutting surface. The collisions shown in the far left and right of this image are a prime examples of this type of collision. The endmill has removed material in order to get to a certain depth, but because the collet is wider it collides with the stock.

NOTE : If there are any collisons in your simulation, you are not ready to post and mill.