In some cases, nesting parameters result in unused sheet material. Reusing that unused material is an excellent way to eliminate waste. This topic will cover how to export the geometry and reuse that material for another nesting job.
The BobCAD part file for this tutorial is available in your C:\BobCAD-CAM Data\BobCAD-CAM V**\Examples folder. In the example file provided, the nesting job has already been created.
In this example, you learn how to edit the default remnant shape, adjust the remnant constraints and export the sheet as a .dxf file.
IMPORTANT: Remnant creation is only available with the Nesting Pro module.
1 Open
the part file Remnant_Sheet.bbcd
2 Right-click
on the 
Nesting Job and select
Edit
3 Click
on 
Nesting Parameters on the left
of the Nesting Wizard to skip to that page or click Next>>
until you get to the Nesting
Parameters page.
4 In
the Advanced group, select the check box next to Remnant Sheet to turn
on remnant sheets. Click the Remnant Sheet button to open the Remnant
Sheet Parameters dialog box.
5 Take
a moment to click on each one of the options from the Default Remnant
Shape drop down and notice the previews for each to get an idea of the
geometry each one will produce.
True Shape |
|
Rectangular |
|
Stepped |
|
Clean Cut |
|
6 Set
the Default Remnant Shape to Clean Cut and click OK.
7 Click Compute to nest the parts, remnants and launch the Remnant Sheet dialog box.
When you compute the nest the Remnant Sheet dialog box will open and
you will be able to preview the possible remnant shape outputs. You can
output the previewed shape to use in other jobs or adjust the preview
by cancelling and adjusting the constraints in the Remnant Sheet Parameters
dialog box. In this lesson we will use the current setting and output
the .dxf file.
1 Notice
that we have set the default Remnant Shape to Clean Cut. Take a moment
to click on each option in the Remnant Shape drop down and notice the
preview of the actual shapes they will produce.
|
2 Set
the shape back to Clean Cut.
3 At
the bottom of the Remnant Sheet dialog box you will see the Geometry group.
In this group you can set the export option to either All Sheets, or Selected
Sheet. In this case, both options will accomplish the same thing since
we only have one sheet. Click the Export button.
4 The
Save As dialog box will open. Select a location to save this .dxf and
set the file name to "Remnant" and click Save.
NOTE: A copy has been saved in your C:\BobCAD-CAM Data\BobCAD-CAM V**\Examples folder. As such, if you try to save in the same location, you will get a warning about that file name existing already. If that happens, just overwrite the file rather than cancel the save.
5 The
Windows Explorer will launch. Notice that our file is highlighted in the
list and the name "Remnant" is now "Remnant-Sheet-1-1.dxf".
6 Minimize the Windows Explorer and hit Cancel on the Remnant Sheet dialog box to close it.
1 Open
the windows file explorer again and drag the .dxf file into the BobCAD-CAM
CAD window.
2 Right-click
in the CAD window to access the context menu and click Select.
3 Once
in selection mode, hold shift and left click the geometry to chain-select
it. Once highlighted copy the geometry. This can be accomplished by either
selecting Copy from the Edit menu, or by using the Ctrl+C keyboard shortcut.
4 Go
back into the Remnant_Sheet.bbcd window and paste the remnant geometry
into the Remnant_Geometry layer.
5 Save file.
1 Hide
the Remnant_Geometry layer and show the Sheet_Geometry layer.
2 Right-click
on the Nesting Job and select Blank/Unblank All to hide the nested parts
and toolpath.
3 Right-click
on CAM Defaults to select a New Job.
4 Select
Milling for the Job Type and click the Stock Wizard button.
5 Click
>> to move on to Stock Type.
6 Select
the radio button for Wireframe and click >>.
7 Select
the Pick Geometry button, chain-select the Sheet_Geometry and click
OK to confirm.
8 Click
>> and then OK.
When cutting the remnant, it is important to always keep in mind that
a cut will always have a width to it. To get the most of the remnant,
we would always want to compensate for our tool width on the outside of
our remnant. Depending on the nested result and the size of our tool,
that cut may have an effect on our nested parts. In this case we will
cut down the center of the line with a tool that will not interfere with
the parts on the sheet. This will only have a small affect on the remnant.
1 Hide
the Sheet_Geometry layer and make the Remnant_Geometry layer visible.
2 Right-click
on 
Machine Setup-1 and select Mill 2 Axis.
3 Click
on the Select Geometry button to hide the Mill Wizard and enable selection
mode.
4 Click
on the line on the left side of the remnant and click OK to confirm.
5 Click
Next>> and set the Total Depth to 25.4.
6 Click
Next>> and remove the Profile Rough from Current Operations.
7 Click
Next>> three times to get to the 
Finish page.
Set the tool Diameter to a value of 6.3500.
8 Click
Next>> and set System Compensation to Off.
9 Click
on Leads in the Feature tree on
the left of the Mill Wizard to jump to the Leads page
or click Next>> until you reach the Leads page.
10 Set
lead to Parallel.
11 Click the Compute button.
Now that the Remnant has been decided upon, exported, brought into the nesting file and cut, you will have two jobs to post code for. The first is the initial nest and the second is the code to cut the remnant sheet free. In the next lesson, we will be Using the Remnant sheet to create a nest for other parts.
