Beginner Guide to Makera CAM and CarveraController

CNC, short for “Computer Numerically Controlled,” describes a family of subtractive fabrication techniques that all share a common feature: they are automated through computer programs, hence the name.

The 2 most common CNC machines are the mill and the lathe. Both work by removing material from an object, referred to as stock. The Carvera machines located in the Connelly Center Generator allow us access to both processes in one machine. The Carvera ecosystem comprises three components. The router (machine), the controller software that manages the router, and the CAM software, which is where jobs are prepared from preexisting files.

The following document is intended as a beginner’s guide for how to use the Carvera Machines and their associated software for 3D milling operations; certain specific or advanced topics will not be covered by this guide. Additionally, this guide aims to avoid regurgitating the content found on the Makera Wiki. A much deeper explanation of the advanced features of Makera CAM and the Carvera Control software can be found here: https://wiki.makera.com/en/home

Makera CAM

CAM, short for “Computer Aided Manufacturing,” software are programs that take existing 2D or 3D design files created in CAD or Vector Graphic Editing software, and convert them into instructions that a CNC machine can interpret and use to fabricate the desired object. CAM programs are to CNC what slicers are to 3D printing. In fact, slicers are technically a type of CAM software, but for additive manufacturing, the processes being an inverse of each other. All CAM software exports what is called “G-Code,” which is a file type containing an ordered list of the coordinates that determine the movements of the cutting or printing head on the machine. This “G-Code” file is what you will prepare using the Makera CAM software.

Stock

The material that is intended to be machined is called the “Stock.” Generally, stock is a piece of raw material shaped in some fashion of rectangular prism; coincidentally, this is the only stock shape Makera CAM will accept. If you intend to machine a nonstandard shape of stock, enter its rectangular dimensions and plan your model placement according to its actual dimensions. In the top left-hand corner, below the main toolbar bar is the Stock window, which shows the material’s dimensions and has a dropdown menu that allows you to select the material type.

Makera Cam uses vectors to execute 2D milling operations. It will accept either “.svg” or “.dxf” file types when using the “Import 2D Files” feature. If you wish to engrave or cut out a rasterized pixelated image, such as a “.png” or “.jpg”, you will first have to select the “Import Image” icon on the toolbar, then right-click on the image and select “Trace Image.” This will open up a new window on the right side of the screen, and you will see features of the image you imported being outlined in purple. In the newly opened window, you will have several options, the most important of which is the threshold option. This option adjusts the cut-off for how large a feature must be to be vectorized. Higher thresholds will ignore blurry or small parts of the image. After tracing the image, the original image will have its visibility toggled off; it is still loaded in the project and can have its visibility re-enabled if you need to redo the image trace. Image tracing works best with high contrast black and white images, but color images will be automatically converted to greyscale images that may need their contrast adjusted, which can be done by selecting the edit tab, then selecting adjust image, and then using the tools that appear in the right-hand panel.

Found in the “2D Toolpaths” icon in the tool tab, Makera CAM supports 5 types:

1. Pocketing

Pocket tool paths are used to clear out cavities in your design. When you select an area using the pocket toolpath, it will clear out the inside of that area to a specified depth.

1. Contouring

Contour tool paths tell the cutting head to follow and cut along a specific line. When selecting an area using the contour toolpath, the path generated will only go along the outside line.

1. Drilling

As the name suggests, the drilling toolpath drills a hole into an object to a specified depth. It is important to use a drilling bit when executing a drilling toolpath. It is highly recommended to enable the retract setting on the drilling operation to protect the bit. Generally, setting it to relative retract, with a height of 1mm, is sufficient. This will allow the bit to do a "Pecking operation," where the bit will lower, cut away material, then retract to regain its speed, then repeat.

1. Chamfering

Chamfering creates a 45-degree straight edge on a surface, requires a chamfer bit to use, and functions similarly to a contour toolpath, in that it follows and cuts along a designated line.

1. Thread Milling

This enables the user to create threading in a hole. The user must first tap (term used to describe drilling a hole with the intention of threading it) a hole using the bit size provided in the information tab of the tool; the hole must be the entire depth you want to thread. You can either create threading within a hole, which is classified as an internal thread, or thread around an object, which is called an external thread.

Select the vectors you wish to generate the toolpath on by either shift-clicking or clicking and dragging over them.

It is important to ensure that the end depth is a negative value; otherwise, the machine will mill the first layer, then attempt to move up the z-axis, despite there being no material there.

If you are cutting through a piece of stock, ensure that the end depth is .5mm lower than the height of the stock.

Pocketing toolpaths support the utilization of more than one kind of tool. You can select the add tool icon to add another type of tool to the toolpath. The order of the tools in the menu is the order they will be used in the milling operation, going from top to bottom. Make sure your larger tool is listed first in this menu, followed by a smaller tool for the detailed work and sharp edges. Other types of operations only accept one type of bit per toolpath.

Make sure to select a bit that is compatible with the material you are milling, and that the bit is set to the corresponding tool slot in your Carvera machine.

When cutting pieces from stock, it is useful to set the path to follow outside with an offset of 0; this will ensure that you receive the correct exterior dimensions on your part.

1. This option will cause the bit to gradually move down into the stock instead of plunging directly in. It is generally good practice to enable this on every toolpath, as it helps to preserve the bit, even on softer materials like wood, where this is not necessary. However, on harder materials such as aluminum, you are at serious risk of severely damaging the bit if you don’t enable this option.

After this process is over, you will see a new toolpath in the function panel under the “Toolpath” tab. Repeat the above steps if you wish to add an additional type of toolpath.

After you have completed all your toolpaths, right-click on any toolpath in the function panel and select “Export.” Make sure all of the paths are selected, then export the paths.

Before proceeding any further, please read and abide by the following safety considerations:

1. Locate the red emergency stop button located next to the machine, ensure it is plugged in, and after turning on the controller, test the button to ensure that it is working.
2. Always ensure that the cover is closed prior to beginning an operation.
3. Never open the cover while the machine is running; this is extremely dangerous.
4. Be careful when handling bits; they are sharp and will easily cut you.
5. Always ensure that your stock is securely emplaced prior to beginning and machining operation.
6. It is VERY IMPORTANT to remember to place a piece of waste board under any stock you intend to cut or drill all the way through. This waste board will protect the bit and the machine itself. Additionally, if you plan on cutting all the way through an object, it is recommended to add an additional .5mm to whatever your maximum depth is to ensure that the bit cuts all the way through.

Failure to follow any of the above may result in severe injury to the user and any bystanders.

To see if the machine is already on, simply open the cover. If the lights on the inside of the cover turn on, then the machine is on; if they do not, it is not powered on. To power on the machine, you must flip a switch located on the bottom, back right side of the machine from the user’s perspective. Once the machine is on and the controller software is booted up, select the top left icon in the menu where it says “N/A Disconnected” with a greyed-out light. In the drop-down menu, select “USB” and “COM3.” This will connect the software to the machine directly.

As mentioned in the safety section, it is important to emplace and secure your stock. The surface of the operating area on the Carvera is covered in threaded holes, which allow the user access to a wide variety of emplacement options and orientations using the workholding tools included in the toolkit. These implements are as follows:

There are 2 different-sized L brackets that can be mounted on either of the anchor points featured in the image above. Your stock should always be retained by one of these L brackets. There are also 4 Top Clamps and 2 Side Clamps included in the toolkit. They can be mounted in the manner seen in the pictures attached to this step.

Now that your stock is properly emplaced and secured, you can proceed with the milling operation. Click the file icon in the bottom left corner of the screen, and select “Upload File” located in the top right corner of the new window. Select the file you want to use, then click “Upload & Select.”

Next, click the gear Icon from the menu in the bottom left corner, and you will be greeted with a new window. Toggle on the vacuum, check the “Auto Z Probe” box, and ensure that your stock area is aligned with the anchor

Finally, ensure that your cover is closed and click “Run.” This will begin the milling process, and from this point forward, everything is automated.

Additional Resources:

1. Carvera Instruction Manual:

https://cdn.shopify.com/s/files/1/0633/3897/1361/files/CARVERA_MANUAL_ENG_a7b10213-f603-40b6-9edb-be94120fcb4c.pdf?v=1679587475

1. Makera CAM Wiki:

https://wiki.makera.com/en/software/MakeraCAM_userguide

1. Makera CAM Official Video Guide:

https://www.youtube.com/playlist?list=PL7zu0ucQCuYQCDNnkkt_-5m-sFaEaTg-5

1. Carvera Official Video Tutorial:

https://youtube.com/playlist?list=PL7zu0ucQCuYRTigCJ4nqRrI0TIhcHHbZl&si=BgRavKe8wxjBQhr4