Has anyone used their 4W JTech laser to make any of those metal business cards like these:
Amazon.com : 100 Pcs Metal Business Card Blanks
If you have, what settings did you use in Lightburn to burn the top layer of paint off so that the silver shined through nicely?
I ran a prototype using various speed settings at 100% laser strength, and you can see where it made a mark, but it did not clear the paint like it was supposed to do, leaving the silver metal exposed. I guess my next try is to run a prototype at various power levels.
I even tried much faster speeds (1000, 900, 800, 700, 600, 500 in/min) at three different power levels (100, 75, 50%), and none of them seemed to work either. Maybe the 4 W laser just isn’t powerful enough to use these cards.
I’m not an expert with lasers, and I’ve only used my 50W fiber laser briefly over the past six months, but I hope the settings below can be adapted for your setup.
One key takeaway I’ve learned when engraving metal cards: the less you burn into the card, the better it looks. The more power you use, the more the engraving darkens as you begin burning the metal itself. In most cases, you only need to remove the top layer of paint or powder coating to reveal the bright, shiny metal underneath.
Also, keep in mind that most affordable metal cards are covered with a simple paint layer rather than a durable powder coat. On that note, high-quality cards from reputable suppliers like Johnson Plastics Plus (https://www.jpplus.com) can cost up to $2 each! I haven’t had the need to use those yet, so the settings below are based on cheaper cards from Amazon, like the ones you referenced.
Key Settings for My 50W Fiber Laser:
- I’m using 60 percent, or 30 of 50 watts total
- The frequency for peak output power of my machine is 40 kHz and I’m cutting that in half so as not to burn the metal
- Passes: 3 (instead of crosshatching, which I found less effective)
Suggested Conversion for a 4W Diode Laser:
- Speed: 100–300 mm/min (start around 200 mm/min)
- Power: 100% (maximize due to lower wattage)
- Passes: 5–20 (multiple passes needed for a visible mark)
- Line Interval: 0.10 mm (diode lasers lack the precision of fiber lasers)
- DPI: 254 (matches the 0.10 mm line interval)
- Possibly use grayscale mode?
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Use the material test function in LB. That will give you a grid of increasing power and decreasing speed. Then you pick the one that looks best.
On a brand new material I have never used before I will run one 10x10 grid from 10%-100% on both speed and power. Then once I see one or two squares that look good or even close to good, run another 5x5 grid with settings that go from one half to two times whatever the values of the selected square are.
I even tried much faster speeds
Faster speeds will give you LESS burn, as the laser is on any given area for less time. If you need more burn, slow down. Overburning, speed it up.
For reference, I looked in my material library for my old 10w diode laser and I have a setting for marking anodized aluminum at 200mm/min @100% and another for marking on PC cases (powder coated steel) at 100mm/min @100%
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Also no laser expert, but I thought the frequency of the laser is what allows it to cut/etch materials. That is why a standard diode laser can cut tinted acrylic but not clear. Likewise, a diode laser can’t actually cut or score metal – al it is doing is removing he anodized or painted outside. A fiber laser, however, is actually removing material.
0.02.
-Tom
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Well, first, my understanding is diode lasers are continuous sources of energy. Whereas CO2 and fiber lasers operate based on pulses of energy, and the frequency is what controls how many of these pulses arrive per unit of time. Lower frequencies mean the pulses are spaced apart more, and higher frequencies is the opposite. Note, I could be wrong about the CO2 being continuous?
With that said, figuring out the settings for power, speed (gantry speed for CO2 or beam scanning speed for fiber) and pulse frequency all together is the tricky part. Below are the three rules of thumb I have jotted down in my notes that are “usually” a good staring point.
But as I start to experiment with different materials like brass and plastics used with 3D printing, along with the desire to just mark versus deep engraving on these different materials, I tend to find myself jumping around with my settings. I’ve tried using a spreadsheet and paper notes, to keep track of what works best for a material, but I just haven’t had enough exposure (pun intended) using my laser to get good at knowing exactly what settings to use when.
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Slow Speed, High Power, Medium Frequency (40 kHz) = Deep Engraving on Metal because slow speed allows for more laser energy per unit area, higher power increases heat input and material removal and medium frequency (40 kHz) balances pulse density—enough to maintain smooth marking without too excessive heating.
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Fast Speed, Low Power, Low Frequency (20 kHz) = light metal etching, plastics, and sometimes surface cleanup of more powerful operations like above. Fast speed minimizes dwell time, reducing heat accumulation, low power prevents excessive material removal or burning and low frequency (20 kHz) means fewer pulses per second, so each pulse is more energetic.
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Slow Speed, Medium Power, High Frequency (Over 100 kHz) = Polishing and Smoothing Surfaces or very fine detail engraving. Slow speed increases dwell time, allowing pulses to build up for a smoother effect, medium power prevents excessive melting and high frequency (100+ kHz) creates a very dense pulse distribution, reducing the impact of each individual pulse as the total energy (power) has to be divided by a high number of individual pulses.
Lastly, I regarding this thread, I believe @mrkrag makes a great point, and one that I simply forgot, which is do test patterns. These can seem tedious (and expensive) for each new material, but they really can help narrow down the settings.
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HI Forrest – lasers generate light energy at specific wavelengths, which can easily be converted into frequency. What are you are describing above is the pulse width when the laser light is modulated using PWM, which can also be described as a frequency. That is generally why we talk about the wavelength a laser generates vs the frequency of the output. As far as I know, all lasers are pulsed to produce a range of output power levels.
Wavelengths of popular laser production techniques:
CO2 Laser = ~10nm
Laser Diodes = ~445nm
Fiber Laser = ~1064nm
I found this article that is geared towards professional lasers, but still has a good description of the parameters.
Based on that article, I still believe the wavelength of the laser itself affects the materials it can cut and engrave.
-Tom
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First, I apologize for misreading your initial question about frequency—I originally thought you were asking about the frequency of individual laser pulses.
Regarding wavelength: Yes, the three types of lasers each produce different wavelengths of “light” (more accurately, energy along the electromagnetic spectrum). These different wavelengths interact with physical objects in distinct ways. For example, certain wavelengths, such as those from fiber lasers, pass through glass. However, ultraviolet (UV) lasers—currently a hot (pun intended) new technology—have much shorter wavelengths that interact directly with the molecules of glass rather than passing through them.
The wavelength of electromagnetic (EM) energy emitted by a laser refers to the distance between two peaks of its wave, or said differently, from the top of a peak to the bottom trough. This wave also has a corresponding frequency, which is the inverse of its wavelength. Wavelength “frequency” measures how many cycles of the wave pass a given point per second. If you were observing a sine wave using an oscilloscope—whether from an AC electrical current, an analog radio transmission, or any other oscillating signal—and you isolated a single wave cycle (from peak to trough), the number of times that cycle repeats per second would define the wave’s frequency.
Returning to the Main Topic:
I did some research, and from what I found, all types of lasers can (and likely do) have versions that operate in either pulsed or continuous-wave modes. In the context of laser cleaning machines—which I find fascinating, I found the this quote from The Google:
“A continuous-wave laser cleaner emits a constant beam of laser light, ideal for cleaning large, flat areas with light contaminants like paint or dust, while a pulsed laser cleaner delivers short bursts of laser energy, better suited for removing stubborn residues like rust.”
Technically, these laser cleaning machines still fall under the category of fiber lasers, because they generate their beams using fiber-optic glass. The core of the fiber is doped with a reactive material that amplifies the seed laser’s energy to produce a usable output. This contrasts with CO2 lasers, which rely on a different process: a seed laser bounces back and forth inside a gas-filled tube, increasing in power until it reaches a usable level.
Pulsed vs. Continuous-Wave Lasers:
What does this distinction mean? Regardless of whether a laser operates in pulsed or continuous-wave mode, it still outputs energy at a specific wavelength, and if measured, the wave of that energy will have a defined frequency. However, this energy does not necessarily have to be emitted in a continuous stream.
One way I understand this concept is by drawing an analogy to radio waves. A traditional analog radio station transmits a continuous wave of energy that never stops. However, a digital radio station likely transmits its signal in extremely fast pulses. Another way to think of it is through digital audio sampling: if you were to record the sound of a vinyl record using a microphone connected to an analog-to-digital converter (ADC), the ADC would “sample” the continuous audio wave at very discrete time intervals. If sampled frequently enough, the result appears to be continuous, even though it consists of discrete data points. Similarly, pulsed lasers operate in a rapid on/off cycle that can sometimes simulate a continuous-wave effect.
Practical Considerations for Laser Cutters/Engravers:
When discussing laser cutters and engravers in general terms, both pulsed and continuous-wave sources are possible. However, for everyday consumer-grade or hobbyist lasers, I was under the impression that diode lasers—such as the JDTech model used with the Onefinity—operate in continuous-wave mode. That said, I have never owned a diode or CO2 laser myself, so I was likely mistaken.
If you own a JDTech diode laser for the Onefinity and see a frequency setting in LightBurn, that suggests to me that the laser’s seed (or pump) diodes are being driven in a pulsed fashion.
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