How To Improve Laser Cutting Accuracy

Laser cutters are powerful machines that use high-powered lasers to burn through a range of materials with precision and speed. Industries that utilize laser cutters include medical, automotive, aerospace, transportation, and electronics. When you consider these highly technical applications, it's clear that the technology behind laser cutting has evolved to unprecedented levels. 

When you purchase a laser cutting machine, you want to get the most out of your investment. Beyond reading your owner's manual and taking advantage of OMTech's extensive knowledge base, how can you improve your machine's performance? Evaluating your laser cutting accuracy could be one avenue to explore.     

Before diving into how you can improve your laser cutting machine accuracy, let's distinguish between two terms we sometimes incorrectly use interchangeably: accuracy and precision. Accurate laser cutting means the machine can slice through the workpiece to create a shape that looks exactly how it appears on its operating software. Alternatively, precision laser cutting means the machine can cut through the workpiece exactly the same way every time, whether accurate or not. 

What Can Reduce Accuracy When Laser Cutting?

There are many advantages to using laser cutting processes over manual methods when fabricating materials. For one, laser cutting tolerance is very low, which means it has a high degree of accuracy. Laser machines also perform their cuts with very little to no material damage. Finally, laser precision is exceptionally high because many lasers utilize fiber optic technology, which helps focus the beam on the same target indefinitely

While the laser cutting function is primarily automated, several steps involve human interaction. Not surprisingly, the steps that require the user to take action are the ones where errors typically occur. What the user selects as the material, the machine's settings, and the workspace's condition all impact the final product. 

Helpful Tips for Improving Laser Cutting Accuracy

There are a few tips you can follow that can ensure your laser cutting accuracy.

First and foremost, the material you choose can significantly impact your laser cutting results. You must choose materials that your machine can effectively fabricate.

Second, ensure that you adjust your laser cutting power and laser settings correctly adjusted for your specified project.

Finally, make sure you correctly secure the workpiece to the workbed. A workpiece that moves around, even slightly, because it is not secure and on a stable surface can create undesirable results.   

Choose the Right Settings for the Type of Material

Understanding that you must calibrate your machine's settings each time you change materials is critical. Even if you are using two different types of similar materials, such as two different kinds of wood, the material properties may differ immensely.

For example, alder and cherry are two varieties of timber popular for laser cutting and engraving. However, because cherry is a harder wood with greater resin count, the laser machine's settings for cherry should be much different than for alder, which is  a softwood with low resin count. Choosing the incorrect settings in this case could reduce accuracy, damage the materials, or even be a safety concern to the user due to a fire risk.

In general, regardless of the medium you choose, thicker materials or those with an uneven surface will negatively impact laser cutting tolerances. It's wise to opt for a thinner workpiece with a smooth, even surface when possible. If you need help determining which setting is correct for the materials you may work with, refer to your laser machine's operating manual.

Adjust and Test Cutting Speeds and Power Intensity

The proper speed adjustment on your machine is vital to your laser cutting accuracy. If your cutting speed is too fast, the laser will not exert the energy needed for each design element on the specific material. The result will be an incomplete pattern or a cut that doesn't go as deep as necessary.

On the other hand, a cutting speed that is too slow results in the laser lingering longer than it should, increasing the laser's intensity. The excessive heat this generates could damage your workpiece and greatly decrease processing accuracy. Test out on a small piece of your material and play around with your laser cut settings prior to engraving on your actual piece. Learn to fully test out laser settings in this article here. 

Use a Smaller Laser Beam Spot Size 

The size of a laser beam's spot is directly related to the length of the laser's focal lens. As the beam passes through the focal lens, it becomes concentrated and forms the spot. A shorter focal lens creates a more focused beam with a smaller spot size. Laser beams with small spots can achieve greater accuracy than those with larger ones.   

Think of your laser beam spot size like you would a tip of a paintbrush. The smaller a paintbrush tip is, the more intricate a design you can paint on a canvas. This idea is similar to laser beam spot sizes. A laser beam with a smaller spot size can more easily cut out patterns with complex designs and fine details. 

Align Your Mirrors 

Aligning your laser beam mirror might sound like an intimidating concept but we promise you it's not. A laser machine operates by generating laser beams from a laser tube and reflecting it on to several mirrors throughout the machine before its final mirror that beams down from the laser head. Aligning your laser beam mirrors will help you laser engrave at the highest quality as the beam will not have obstructed paths. Learn to fully align your laser beams by reading this article here: Laser Engraver Mirror Alignment. 

Stabilize Your Workbench

Your workbench is a crucial component of laser cutting accuracy. As with any crafting or technical project that requires low tolerance and precision, the last thing you want is for your surface stability to ruin your final product. A table that moves or vibrates as your laser cutter is operating or is on the verge of collapse is not an ideal workbench for your machine. 

How Accurate Can You Get With Laser Cutting?

The heat-affected zone (HAZ) is another term you should understand when evaluating the laser cutting accuracy. The HAZ refers to the workpiece area that the laser alters but is not a part of the actual cut. Think of the HAZ as collateral damage. Ideally, you want as minimal a HAZ as possible to ensure greater accuracy.   

Laser cutting machines are so accurate that they can achieve a cut width of 1/10,000th (0.0001) of an inch. Considering that this measurement is 1/10th of an average human hair, you can appreciate how accurate that is. 

Achieve Supreme Accuracy With Top-of-the-Line Laser Cutting Machinery

If you follow these tips, you can perform with high accuracy with your laser cutter. To create the best work, you need to have the best equipment. Check out OMTech's line of quality CO2 machines and laser accessories today and gain a partner in your laser cutting adventure.