I have a theory that it’s better to etch line art by setting the ‘to be etched line art’ to hairline stoke, then lowering the power and frequency in the print dialog box.
Etching line art this way appears to be more efficient but I have no evidence. It certainly takes less time to run the job and requires less jerky motion from the gantry
Thoughts? There’s a paper in here somewhere. Or at least a blog post…
I’ve done it. I wouldn’t lower the frequency, but I’ve lowered the power and ramped up the speed before.
When vector etching cardstock, I found that I had to go to something like 5% power and 100% speed to get a usable etch (as opposed to cut).
I’ve done it too. I just wish I knew how to assess the energy use and wear and tear of both methods so that I could say with confidence, “Do it this way. It uses less energy and is better for the longevity of the machine.”
I see them as doing different purposes. Vector etching is perfect when what you are dealing with is fine, precise lines. You can’t do broad areas or fills with vector etching. Raster etching treats everything as a fill, essentially. I wouldn’t trust raster etching to get the finest of lines or the most precise detail, even though it’s probably fine (I think raster etching is limited to 500dpi resolution, which is coarser than vector etching can theoretically give you).
Vector etching is decidedly faster for a few lines, since raster etching has to scan the entire raster area to etch. But the machine moves faster when rastering than when vectoring, so if you have a lot of fine detail vectoring can take longer. Raster speed depends only on the size of the image, not on the complexity of it.
I would say that Epilog designed the machine to do both, with the understanding that the machines would be used in a commercial production environment. Commercially, more rastering is done than vectoring, so that’s probably where the emphasis in machine longevity went into it. I wouldn’t personally consider machine longevity as a major factor in deciding how to do a particular job.
As for energy use… It’s probably a wash, with a slight benefit to the vector etch. To get similar results on the material, similar amounts of energy still have to be imparted to the target. Whether you do that slowly at low power, or fast at higher power probably doesn’t matter. The rapid speed of the gantry when rastering probably uses slightly more energy than the careful movements of vectoring, but it’s probably pretty small.
But I don’t use high power to “etch” line art in vector mode. the job in that mode takes 30 seconds opposed to 4 minutes in raster mode
“high speed/high power” is raster, “low speed, low power” is vector.
The gantry moves at high speed in raster mode, and the laser is at high power (when it’s on). Over the course of the 4 minutes to raster your line art, the laser is on for a very short period of time, but moving fast at high power when it does so. The rest of the time, it is moving over parts of the work where there is nothing to etch, but it still has to go over them because of the way raster stuff works. So it’s moving the gantry a lot to draw your art, but it’s moving (relatively) fast.
In vector mode, the gantry moves slower (so it has better control to make curves), and uses lower laser power. The laser is on for the whole 30 seconds (except when it is quickly moving from one spot to another without etching), and it doesn’t need to go to places where there aren’t lines to draw. So it’s moving the gantry as little as possible to draw your art, but it’s going (relatively) slowly.
That makes sense. Thanks. Is there a device we can plug the laser into that will track power usage over time. That would be cool.
I’m asking all of this bc my course is a sustainable design course. So optimizing our production process for low energy consumption (using lasers !!) is a thing I want to know more about.
for anyone who is interested, I found this paper:
Laser Cutting; Energy and Resource Efficiency; Environmental Impact; Sustainable Production
a lot of cool intel in there like how much energy each part of the cutter uses. They allude to the machine operator being able to make decisions that have an impact on energy consumption, but i can’t find the details of that. Maybe Ill reach out to the authors
The author’s response (seems obvious now that I read it): As the consumed energy depends on cutting time and applied power level, the difference in power demand will provide the answer to your question. Do you have an idea about the average power demands for both cases?
Of course, this doesn’t address what @Blaise claims, that in raster mode the laser shuts on and off a lot. So even if the power setting is X, it’s hard to determine how many seconds the laser is actually on a drawing power
Like I said, to get similar results in etching wood, you have to put roughly the same amount of energy into the wood whether you are going low and slow (vector) or high and fast (etch).
We can get a Kill-o-Watt meter, which plugs into the wall and the laser cutter would plug into it, and it would tell us the energy usage for a job.
We should keep in mind that the exhaust fan and air compressor both take energy as well, but those are both fairly constant power usage, so total energy usage would be proportional to time.
I would like that. That paper claims that exhaust time is significant. We need a power strip that has a kilowatt meter built in
The main company that makes the Kill-A-Watt devices (it’s a brand name, there may be others out there) appear to have recently discontinued the power strip version. It’s on their main web site, but not in their web store, and only 3rd-party merchants in the Amazon Marketplace sell it for about $200.
But here’s the page of P3 International with their energy saver devices. http://www.p3international.com/products/energy-savers.html
We could get a Kill-A-Watt EZ or similar tool and plug a power strip into it.
Maybe I can ask my chair to split the cost…
Based on that image, I would expect that the vector mode dumped more energy into the cardstock, since it looks like the vector mode etch is deeper and darker. But it’s very likely that the raster mode used more energy overall due to the compressor and fan.