October 7, 2024
After they’re machined and cleaned, many parts are engraved or marked. Engraving is commonly used to identify the metal alloy of the part, track part lot numbers, or add specific part numbers.
For example, a stainless steel component might be engraved with:
SS303
#002
That would indicate to people that the part is 303 stainless steel, and is the second lot of parts.
Anything can be engraved on metal parts, but it is a secondary process that happens after machining, so it adds to the manufacturing time and costs. You only want to engrave information that’s necessary.
The two most common ways to engrave metal parts are laser engraving, and CNC engraving. The same general principles apply, but they are two different machines, and mark the parts differently. In some cases, laser engraving is better, and other times CNC engraving is best.
We’ll explain how each process works, and what its recommended use cases are.
The biggest difference between laser engraving and CNC engraving is the actual engraving process. They both achieve similar results.
A laser engraver uses a high-power laser to heat and vaporize a tiny amount of material off the surface of a part. Because there’s no contact, the part generally doesn’t need to be fixed.
A CNC engraver uses a sharp cutting tool that touches the surface of the part to remove material. This process usually engraves a single part at a time, and the part is secured in a vice.
The first laser engraving machine was purchased over 40 years ago, in 1978. Since then, the technology has improved drastically, and laser engravers are more accessible. Laser engravers use heat to burn and permanently mark a surface.
They can be used to create artwork on a piece of wood, glass, or metal. The machine works similarly to a CNC machine. You use a computer program to upload the image and text you want engraved, hit go, and the laser moves around, etching your design onto the surface.
Different settings can be adjusted depending on the material you’re engraving and increase or decrease the intensity of the laser marking. If you want a more prominent marking, the speed can be slowed down, so the laser burns the material for longer.
Setting up the laser engraver can take some time, and you might need to make adjustments if the marking isn’t clear enough. It can also be challenging to mark a curved or uneven surface. But, once you get the right settings right, laser engraving is a quick process. And a tray of 100+ parts can be set in the engraver to be marked simultaneously.
Laser engraving is used for simple part numbers, and more complex engravings like a barcode or QR code.
A CNC engraver setup is more like a drill press. There is a sharp, pointy cutting tool that’s dragged across the part surface to mark the surface of the part. The engraver is connected to a computer program where the marking details are entered.
Generally, this engraving process is used specifically for hard metal parts.
The parts are held in a vice attached to the engraving table while the cutting tool moves around to mark the part or lot numbers. Unlike a laser engraver, a CNC engraver usually works on one part at a time. The engraving takes a few seconds, and then the cutting tool resets and is ready for the next part. Because the parts need to be switched out one by one, this engraving requires more human attention.
CNC engraving is commonly used in the automotive, aerospace, healthcare, and oil and gas industries. It’s used to add simple numbers to parts, and not ideal for more complex engravings.
These part marking processes are similar, but they both have specific pros and cons.
Engraving parts is a common secondary process. Both laser engraving and CNC engraving are great ways to add important numbers and markings to your parts. This can help with inventory management and tracking parts. Reach out to our team to learn more about our secondary manufacturing operations.