Electronics Workflows with the Desktop CNC Milling Machine – Bantam Tools

While the Bantam Tools Desktop CNC Milling Machine is designed for rapid prototyping in aluminum, we know folks love making electronics with our CNC machines, and we're not going to stop empowering you to make circuit boards. And with the Bantam Tools Desktop CNC Milling Machine’s multi-material capabilities and 7”x9”x3.5” working volume, transitioning from machining PCBs to enclosures for your electronics projects is fast and easy.

In this guide we cover:

What Gerber and EAGLE files are
Importing PCB designs using G-code files
Importing PCB designs using EAGLE files
Setting up your file in the Bantam Tools Milling Machine Software
Electronics tools and accessories checklist

What are Gerber files?

A Gerber is a 2D vector image file format, and it’s the industry standard for conveying information about a printed circuit board (PCB). If you’re getting your PCB made by a circuit board manufacturer, a set of Gerber files is what they’ll ask for. Gerber files can describe the copper traces, component placement, solder masks, silkscreen markings, and many other layers or aspects of a PCB.

Learn more about working with Gerber files.

What are EAGLE files?

EAGLE (an acronym for “easily applicable graphical layout editor”) is an app integrated into Fusion 360 and is specifically intended for designing printed circuit boards. It has tools for creating circuit schematics and for laying out the physical wiring and component placement of circuit boards. Our software can read EAGLE board files (with .brd extension) and cut them on the milling machine with almost no configuration or setup on the user’s part.

Learn more about working EAGLE files.

PCB Workflow with Gerbers

With the base package of the Bantam Tools software, you can machine circuit boards using free Gerber to G-code conversion solutions, such as FlatCAM. This free software converts Gerber and Excellon (Drill) files to G-code, which you can then import directly into the Bantam Tools software.

Note: Our dedicated support guide offers more details on using FlatCAM.

Loading Gerbers into the Bantam Tools software requires one additional step: When importing your file, the Bantam Tools software will show a pop-up window that will prompt you to point to the first Gerber file you’ve selected to the next Gerber file you want to machine.

PCB Workflow with EAGLE

Bantam Tools software subscribers have access to our built-in PCB milling workflow, which allows you to directly import Gerber or EAGLE board files into the Bantam Tools software. If you’re working with EAGLE, the electronics workflow will be even faster. After you’ve designed your circuit board in EAGLE, simply go to the Initial Setup tab in the Bantam Tools software and import your .brd file.

Note: If you’re a Desktop PCB Milling Machine user, you automatically have access to our built-in EAGLE integration since your machine is specifically designed for prototyping electronics.

Setting Up Your Design File

Whether you’re working with Gerber or EAGLE files, the Bantam Tools software’s real-time preview will change/update the color of your stock from blue to copper. To set up your file, you’ll need to select your tools. The speeds and feeds for the tools you select can be found and customized in the Custom Tool Library.

In the Toolpaths dropdown menu, there are a number of PCB-specific settings that you can choose from.

Side to Mill: If you’re milling a double-sided board, you can toggle to select which side you want the Desktop CNC Milling Machine to mill.
Traces, Holes, and Outline: Toggle between these settings to choose which features of your circuit board you want to machine (depending on the layer you’re machining).
Trace Depth: Adjust the depth of your traces. We typically like to machine at 0.003”, but this may vary depending on your design.
Trace Clearance: Tell the Desktop CNC Milling Machine how much extra copper you want to clear away between the traces.
User Detail Tool Everywhere: Tell the Desktop CNC Milling Machine to use the smallest tool you’ve selected for your file.

Tools & Accessories Checklist

If machining electronics is your primary goal, here’s a list of tools and accessories we recommend to enhance your PCB prototyping workflow with the Bantam Tools Desktop CNC Milling Machine: