Sourceshttps://github.com/tinkerator/snappy

The snappy tool

The snappy command line tool demonstrates features of the "zappem.net/pub/net/snappy" package for driving a Snapmaker A350 machine. This README covers example ways to use the tool.

If you have any questions about the tool, or want to request a feature, please use the Github bug tracker for this package.

Homing the device

Before you can command the device, you need to home it. With the snappy tool, you can do this.

$ ./snappy --home

If you have an enclosure, you can also combine this operation with enabling the enclosure fan at 100% (fumes from using the machine can be unpleasant and the device provides this feature to help exhaust them):

$ ./snappy --home --fan=100

Adjusting the position of the tool head

Once you have homed the device, in the current coordinate system, you can direct it to move to an absolute position (CAUTION: this is usually a safe position after homing, but may not be if you have something large on the work platform):

$ ./snappy --x 192.5 --y 170 --z 113 --move

It is often more convenient to move relative to the current location. You can observe the current location as follows:

$ ./snappy --locate
2025/05/25 07:29:27 at (27.67,-38.21,263.10) offset=(-135.37,-102.45,-49.90)

The offset entry here captures the machine coordinates of the work origin. This origin is a useful concept for adjusting to the details of your system and project. Each tool head has different needs based on the relative offset of the business end of the tool and the machine’s movement mechanism. Practically, you nudge the head into the desired position with commands like this:

$ ./snappy --nudge-x 3
$ ./snappy --nudge-y 4
$ ./snappy --nudge-z -0.5

You can combine these command line options to perform non-Manhatten movement too, for example:

$ ./snappy --nudge-x 3 --nudge-y 4 --nudge-z -0.5

The provided numbers are in units of mm and looking at the machine from the front:

You can provide floating point numbers for these nudges, and the machine is quite precise. For example, ./snappy --nudge-z -0.05 will make a 50 micrometer movement.

Setting the work origin

For working with the laser(s) and CNC bits, you are typically operating on the surface of something else. Snapmaker provides some strategies for adjusting to this, but it possible to use the snappy tool to set things up fairly efficiently.

CAUTION When changing the tool head, the system may be confused into running the head at full power the moment you connect the power to it. This is really unfortunate! SO ALWAYS POWER THE SYSTEM DOWN BEFORE ATTACHING ANY OF THE TOOLHEADS!!

This section has a subsection for each tool used. Over time, we’ll likely include more subsections here.

The 1.6W blue laser tool head

CAUTION Using the laser REQUIRES USE OF THE EYE PROTECTION GLASSES. The enclosure for the Snapmaker looks similar in color to these goggles, but based on online sources and the author’s experience, the laser light does NOT SEEM TO BE APPROPRIATELY FILTERED BY THIS ENCLOSURE. The enclosure also has many metalic surfaces and gaps through which laser light can and does find a way out. Don’t risk eye damage, and DO wear the glasses supplied with the laser.

To calibrate this head, use --nudge-{x,y,z} commands to lower the head until the lower end of the lens cylinder physically touches the surface of the calibration card on the work surface. Next --nudge-z 5.6 to raise the tool head up above the surface. The value 5.6 (mm) is the calibrated value of the author’s 1.5W laser device. Yours might be different.

Once in this position, enter the command:

$ ./snappy --set-origin
$ ./snappy --locate
2025/05/25 11:54:13 at (0.00,0.00,0.00) offset=(-135.37,-102.45,-49.90)

This will set the work coordinate system relative to the current point of the laser. For the laser, if 5.6 is a good setting for your tool head, while using the same surface you should not need to change the Z value (height) of the tool unless you have to --home the device again. Generally, --home resets the work coordinate system.

However, you will likely need to reposition the head in the X & Y position, with --nudge-{x,y} adjustments. Once you get the device into the preferred location for working, set the final work origin, with ./snappy --set-origin again.

Once the work origin is set, you can always return the tool head to it with the following command:

$ ./snappy --goto-origin

Accurately adjusting to the desired work origin can be detailed and frustrating process. In some cases, adjusting by eye is good enough. If you desire more accuracy, there are a few methods that can be performed with this laser head. They include:

Using the lowest power light setting for the laser

TODO this turns on the laser at a low light setting, and you visually align it with some reference point on the surface you consider the origin point. Looking at the laser, no matter how low power it is at, however, seems questionable.

Using the camera for alignment

TODO this uses a test pattern, and then compares a photo of that pattern to compute the relative offset of the center of a photo and the center of the test pattern.

Using precisely placed reference points

TODO this is useful when aligning the CNC and the Laser module work origins. Where the reference points are CNC drilled holes, this method can also be used to align the laser on both sides of a surface. For example, when working with a double sided PCB.

The 10W blue laser tool head

TODO

The 2W IR laser tool head

TODO

The 50W (default) CNC tool head

TODO

The 200W CNC tool head

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