Atomstack A5 20W in-Depth Review And Test – Is it Any Good?

The Atomstack A5 engraver features a laser diode that emits around 4.5W of optical power. While the machine is promoted as having 20W, this probably refers to the input power watts. The laser diode is a fixed focus diode.

In the past, some laser engravers had an adjustable focus feature. This may seem convenient initially but becomes less practical over time. With a fixed focus system, there are no obstructions in the path of the beam. The result is a narrower focus and a faster focusing process than you get with adjustable focus system.

The machine’s engraving module has a protective shield. However, it’s still crucial to wear the provided safety goggles. For even greater protection, I suggest investing in higher-quality goggles with OD6+ protection. Here are some protective laser glasses that I recommend:

AVAILABLE ON AMAZON

Focusing Procedure

To achieve the best cutting results, position the engraving head 2mm above the surface. You can do this by placing a 2mm thick acrylic sheet or shim under the laser head. After that, lower the head onto the shim. Once the head is positioned correctly, tighten the z-axis screws with a hex key to secure it in place. Remember to remove the shim after the head is in position.

Cutting and Engraving Different Materials

With the Atomstack A5 20W, you can engrave a wide variety of materials and even perform some cutting tasks. Some of the materials you can engrave include wood, leather, cotton (clothing), rubber, paper, fruit, foam, acrylic, and black anodized aluminum.

You can also cut wood, paper, tape, cloth, acrylic, and cardboard.

This machine cuts paper and tape in a single pass. For thicker materials like cardboard or wood, multiple passes may be necessary.

Software and Supported Formats

The Atomstack A5 20W is compatible with LaserGRBL software. While it’s adequate for some testing purposes, I opted to switch to Lightburn software, which is more advanced.

LaserGRBL allows importing of both vector files (NC, BMP, JPG, PNG, DXF, etc.) and bitmap image files (BMP, JPG, PNG, and GIF).

Lightburn offers support for a broader range of file formats, including AI, SVG, DXF, PDF, HPGL, PLT, and RD for vector files, and PNG, JPEG, BMP, TIFF, TGA, and GIF for image files.

Our Test Results

We conducted a standardized test on the Atomstack A5 20W, which we typically perform on all laser engravers and cutters.

Read on for the results.

Wood Engraving

The engraving pattern we use for our standard tests is intended to demonstrate the engraving capabilities of any machine we test. We use different settings as this allows us to assess the laser beam’s effectiveness.

You can get the test file we use HERE.

Power Scale

The power scale test pattern demonstrates the machine’s engraving ability at varying power levels and speeds. The power levels are adjusted in 10% increments from 10% to 100%, while the speeds used are 600, 1200, 1800, and 2400mm/min. However, the readings may be obscured by the smoke stains.

Interval Scale

The interval scale test determines whether the laser focus spot shape is square or rectangular. The scanning interval is gradually increased from 0.1mm to 0.5mm to observe how the laser beam shape changes when scanning horizontally and vertically.

From the test results, it’s clear that the laser beam shape is rectangular since it exhibits different behaviors when scanned in the horizontal and vertical directions. The exact spot shape can be estimated accurately during the engraving test on anodized aluminum.

Photo Engraving

Below is a test where we engraved a small 20mm photo while varying the maximum laser power. Engraving photos can be a slow process since the laser head needs to scan line by line. For larger photos, be prepared to wait for a few hours for the engraving to finish.

Vector Image Engraving

Engraving vector images is significantly faster as the laser head can directly follow the lines, unlike with bitmap images where the laser must scan line by line. However, vector images cannot be engraved with grayscale variations.

Our test includes an engraving of a cute Tit bird photo which took only a few minutes to complete. In the software, you have the option to fill closed shapes with a pattern. For this image, the shape was filled by scanning with a 0.1mm step.

To make larger engravings faster, you could increase the step to 1mm or more. This will result in a raster or grid pattern.

Anodized Aluminum Engraving

The next test we conducted using the Atomstack A5 20W laser was on a black anodized aluminum scrap. The test pattern was designed to assess the focus dot size in both horizontal and vertical directions, as well as the impact of speed. In the following sections, we look at the individual components of this test pattern.

The interval scale is once again the most crucial part. By scanning both vertically and horizontally with various interval steps, we can estimate the size of the laser dot. The results indicate that the laser dot is rectangular, roughly 0.1mm in width and 0.35mm in height. With a larger step, the lines no longer connect, reinforcing this conclusion.

Below are the images captured with an Andonstar AD407 digital microscope.

The next test involves varying text sizes. From the results, it is evident that 2mm text size is legible, while 1mm text height is illegible. There is also some axis wobbling, but this is most likely due to mechanical factors.

However, keep in mind that the speed used for this test (600mm/min) could have contributed to the results. Lowering the speed could improve accuracy, as demonstrated later in the tests.

The image below shows two sets of squares on the right side, where one square is engraved inside the other. The inner square is engraved at a speed of 1000mm/min while the outer square is engraved at 100mm/min.

The wobbling that is more pronounced at higher speed is likely due to mechanical factors. However, the brightness of the engraved pattern appears to be unaffected by the speed.

The lower two squares show the effect of the rectangular dot shape. As you can see, the vertical lines are noticeably thinner than the horizontal lines.

Laser Focus Distance Test

This test aims to demonstrate how the size of the laser dot increases as it penetrates deeper into the material. The deeper the dot stays focused, the thicker material it can cut.

To achieve this, we progressively increase the focus distance by 3mm for each square.

The zero mm square represents the optimal focus setting (using a 2mm shim). For the 3mm square, the test piece is lowered 3mm below the optimal focus position to determine the size of the dot 3mm into the material. This same principle applies for the larger distances as well.

From the test, lowering the focus by 3mm does not significantly increase the size of the dot. The horizontal line remains nearly the same size, while the vertical line appears thicker.

As we go further down, the dot increases. At 6mm and 9mm, the dot becomes noticeably thick and loses its rectangular shape.

The thickening effect can be useful when engraving larger objects with low detail, as it allows for faster engraving with larger step intervals.

Acrylic

We tested 3mm black acrylic (also known as plexiglass) at a speed of 600mm/min. The engraving and cutting yielded satisfactory results with a neat cut edge.

We also tested blue acrylic. However, this test was unsuccessful as the blue color did not absorb the laser light effectively. It is likely that the material was not dark enough, and despite using full power for 50 passes, only minor melting was observed without any sign of engraved letters. Therefore, it can be concluded that the Atomstack A5 20W laser machine is capable of cutting and engraving only on very dark acrylic.

Plywood Cutting Test

The cutting test was conducted on 3mm and 6mm thick Poplar plywood at three different speeds. Both scanning directions, horizontal X-axis (left-right) and vertical Y-axis (back to front), were tested since the cutting performance varies in each direction due to the rectangular shape of the dot.

Below are the results: